Layouts and Rendering in Rails
This guide covers the basic layout features of Action Controller and Action View. By referring to this guide, you will be able to:
-
Use the various rendering methods built in to Rails
-
Create layouts with multiple content sections
-
Use partials to DRY up your views
1. Overview: How the Pieces Fit Together
This guide focuses on the interaction between Controller and View in the Model-View-Controller triangle. As you know, the Controller is responsible for orchestrating the whole process of handling a request in Rails, though it normally hands off any heavy code to the Model. But then, when it's time to send a response back to the user, the Controller hands things off to the View. It's that handoff that is the subject of this guide.
In broad strokes, this involves deciding what should be sent as the response and calling an appropriate method to create that response. If the response is a full-blown view, Rails also does some extra work to wrap the view in a layout and possibly to pull in partial views. You'll see all of those paths later in this guide.
2. Creating Responses
From the controller's point of view, there are three ways to create an HTTP response:
-
Call render to create a full response to send back to the browser
-
Call redirect_to to send an HTTP redirect status code to the browser
-
Call head to create a response consisting solely of HTTP headers to send back to the browser
I'll cover each of these methods in turn. But first, a few words about the very easiest thing that the controller can do to create a response: nothing at all.
2.1. Rendering by Default: Convention Over Configuration in Action
You've heard that Rails promotes "convention over configuration." Default rendering is an excellent example of this. By default, controllers in Rails automatically render views with names that correspond to actions. For example, if you have this code in your BooksController class:
def show @book = Book.find(params[:id]) end
Rails will automatically render app/views/books/show.html.erb after running the method. In fact, if you have the default catch-all route in place (map.connect :controller/:action/:id), Rails will even render views that don't have any code at all in the controller. For example, if you have the default route in place and a request comes in for /books/sale_list, Rails will render app/views/books/sale_list.html.erb in response.
| The actual rendering is done by subclasses of ActionView::TemplateHandlers. This guide does not dig into that process, but it's important to know that the file extension on your view controls the choice of template handler. In Rails 2, the standard extensions are .erb for ERB (HTML with embedded Ruby), .rjs for RJS (javascript with embedded ruby) and .builder for Builder (XML generator). You'll also find .rhtml used for ERB templates and .rxml for Builder templates, but those extensions are now formally deprecated and will be removed from a future version of Rails. |
2.2. Using render
In most cases, the ActionController::Base#render method does the heavy lifting of rendering your application's content for use by a browser. There are a variety of ways to customize the behavior of render. You can render the default view for a Rails template, or a specific template, or a file, or inline code, or nothing at all. You can render text, JSON, or XML. You can specify the content type or HTTP status of the rendered response as well.
| If you want to see the exact results of a call to render without needing to inspect it in a browser, you can call render_to_string. This method takes exactly the same options as render, but it returns a string instead of sending a response back to the browser. |
2.2.1. Rendering Nothing
Perhaps the simplest thing you can do with render is to render nothing at all:
render :nothing => true
This will send an empty response to the browser (though it will include any status headers you set with the :status option, discussed below).
| You should probably be using the head method, discussed later in this guide, instead of render :nothing. This provides additional flexibility and makes it explicit that you're only generating HTTP headers. |
2.2.2. Using render with :action
If you want to render the view that corresponds to a different action within the same template, you can use render with the :action option:
def update @book = Book.find(params[:id]) if @book.update_attributes(params[:book]) redirect_to(@book) else render :action => "edit" end end end
If the call to update_attributes_ fails, calling the +update action in this controller will render the edit.html.erb template belonging to the same controller.
| Using render with :action is a frequent source of confusion for Rails newcomers. The specified action is used to determine which view to render, but Rails does not run any of the code for that action in the controller. Any instance variables that you require in the view must be set up in the current action before calling render. |
2.2.3. Using render with :template
What if you want to render a template from an entirely different controller from the one that contains the action code? You can do that with the :template option to render, which accepts the full path (relative to app/views) of the template to render. For example, if you're running code in an AdminProductsController that lives in app/controllers/admin, you can render the results of an action to a template in app/views/products this way:
render :template => 'products/show'
2.2.4. Using render with :file
If you want to use a view that's entirely outside of your application (perhaps you're sharing views between two Rails applications), you can use the :file option to render:
render :file => "/u/apps/warehouse_app/current/app/views/products/show"
The :file option takes an absolute file-system path. Of course, you need to have rights to the view that you're using to render the content.
| By default, if you use the :file option, the file is rendered without using the current layout. If you want Rails to put the file into the current layout, you need to add the :layout ⇒ true option |
2.2.5. Using render with :inline
The render method can do without a view completely, if you're willing to use the :inline option to supply ERB as part of the method call. This is perfectly valid:
render :inline => "<% products.each do |p| %>
<%= p.name %>
<% end %>"
| There is seldom any good reason to use this option. Mixing ERB into your controllers defeats the MVC orientation of Rails and will make it harder for other developers to follow the logic of your project. Use a separate erb view instead. |
By default, inline rendering uses ERb. You can force it to use Builder instead with the :type option:
render :inline => "xml.p {'Horrid coding practice!'}", :type => :builder
2.2.6. Using render with :update
You can also render javascript-based page updates inline using the :update option to render:
render :update do |page| page.replace_html 'warning', "Invalid options supplied" end
| Placing javascript updates in your controller may seem to streamline small updates, but it defeats the MVC orientation of Rails and will make it harder for other developers to follow the logic of your project. I recommend using a separate rjs template instead, no matter how small the update. |
2.2.7. Rendering Text
You can send plain text - with no markup at all - back to the browser by using the :text option to render:
render :text => "OK"
| Rendering pure text is most useful when you're responding to AJAX or web service requests that are expecting something other than proper HTML. |
| By default, if you use the :text option, the file is rendered without using the current layout. If you want Rails to put the text into the current layout, you need to add the :layout ⇒ true option |
2.2.8. Rendering JSON
JSON is a javascript data format used by many AJAX libraries. Rails has built-in support for converting objects to JSON and rendering that JSON back to the browser:
render :json => @product
| You don't need to call to_json on the object that you want to render. If you use the :json option, render will automatically call to_json for you. |
2.2.9. Rendering XML
Rails also has built-in support for converting objects to XML and rendering that XML back to the caller:
render :xml => @product
| You don't need to call to_xml on the object that you want to render. If you use the :xml option, render will automatically call to_xml for you. |
2.2.10. Options for render
Calls to the render method generally accept four options:
-
:content_type
-
:layout
-
:status
-
:location
The :content_type Option
By default, Rails will serve the results of a rendering operation with the MIME content-type of text/html (or application/json if you use the :json option, or application/xml for the :xml option.). There are times when you might like to change this, and you can do so by setting the :content_type option:
render :file => filename, :content_type => 'application/rss'
The :layout Option
With most of the options to render, the rendered content is displayed as part of the current layout. You'll learn more about layouts and how to use them later in this guide.
You can use the :layout option to tell Rails to use a specific file as the layout for the current action:
render :layout => 'special_layout'
You can also tell Rails to render with no layout at all:
render :layout => false
The :status Option
Rails will automatically generate a response with the correct HTML status code (in most cases, this is 200 OK). You can use the :status option to change this:
render :status => 500 render :status => :forbidden
Rails understands either numeric status codes or symbols for status codes. You can find its list of status codes in actionpack/lib/action_controller/status_codes.rb. You can also see there how it maps symbols to status codes in that file.
The :location Option
You can use the :location option to set the HTTP Location header:
render :xml => photo, :location => photo_url(photo)
2.2.11. Finding Layouts
To find the current layout, Rails first looks for a file in app/views/layouts with the same base name as the controller. For example, rendering actions from the PhotosController class will use /app/views/layouts/photos.html.erb. If there is no such controller-specific layout, Rails will use /app/views/layouts/application.html.erb. If there is no .erb layout, Rails will use a .builder layout if one exists. Rails also provides several ways to more precisely assign specific layouts to individual controllers and actions.
Specifying Layouts on a per-Controller Basis
You can override the automatic layout conventions in your controllers by using the layout declaration in the controller. For example:
class ProductsController < ApplicationController layout "inventory" #... end
With this declaration, all methods within ProductsController will use app/views/layouts/inventory.html.erb for their layout.
To assign a specific layout for the entire application, use a declaration in your ApplicationController class:
class ApplicationController < ActionController::Base layout "main" #... end
With this declaration, all views in the entire application will use app/views/layouts/main.html.erb for their layout.
Choosing Layouts at Runtime
You can use a symbol to defer the choice of layout until a request is processed:
class ProductsController < ApplicationController layout :products_layout def show @product = Product.find(params[:id]) end private def products_layout @current_user.special? ? "special" : "products" end end
Now, if the current user is a special user, they'll get a special layout when viewing a product. You can even use an inline method to determine the layout:
class ProductsController < ApplicationController layout proc{ |controller| controller. # ... end
Conditional Layouts
Layouts specified at the controller level support :only and :except options that take either a method name or an array of method names:
class ProductsController < ApplicationController layout "inventory", :only => :index layout "product", :except => [:index, :rss] #... end
With those declarations, the inventory layout would be used only for the index method, the product layout would be used for everything else except the rss method, and the rss method will have its layout determined by the automatic layout rules.
Layout Inheritance
Layouts are shared downwards in the hierarchy, and more specific layouts always override more general ones. For example:
class ApplicationController < ActionController::Base layout "main" #... end class PostsController < ApplicationController # ... end class SpecialPostsController < PostsController layout "special" # ... end class OldPostsController < SpecialPostsController layout nil def show @post = Post.find(params[:id]) end def index @old_posts = Post.older render :layout => "old" end # ... end
In this application:
-
In general, views will be rendered in the main layout
-
PostsController#index will use the main layout
-
SpecialPostsController#index will use the special layout
-
OldPostsController#show will use no layout at all
-
OldPostsController#index will use the old layout
2.2.12. Avoiding Double Render Errors
Sooner or later, most Rails developers will see the error message "Can only render or redirect once per action". While this is annoying, it's relatively easy to fix. Usually it happens because of a fundamental misunderstanding of the way that render works.
For example, here's some code that will trigger this error:
def show @book = Book.find(params[:id]) if @book.special? render :action => "special_show" end end
If @book.special? evaluates to true, Rails will start the rendering process to dump the @book variable into the special_show view. But this will not stop the rest of the code in the show action from running, and when Rails hits the end of the action, it will start to render the show view - and throw an error. The solution is simple: make sure that you only have one call to render or redirect in a single code path. One thing that can help is and return. Here's a patched version of the method:
def show @book = Book.find(params[:id]) if @book.special? render :action => "special_show" and return end end
2.3. Using redirect_to
Another way to handle returning responses to a HTTP request is with redirect_to. As you've seen, render tells Rails which view (or other asset) to use in constructing a response. The redirect_to method does something completely different: it tells the browser to send a new request for a different URL. For example, you could redirect from wherever you are in your code to the index of photos in your application with this call:
redirect_to photos_path
You can use redirect_to with any arguments that you could use with link_to or url_for. In addition, there's a special redirect that sends the user back to the page they just came from:
redirect_to :back
2.3.1. Getting a Different Redirect Status Code
Rails uses HTTP status code 302 (permanent redirect) when you call redirect_to. If you'd like to use a different status code (perhaps 301, temporary redirect), you can do so by using the :status option:
redirect_to photos_path, :status => 301
Just like the :status option for render, :status for redirect_to accepts both numeric and symbolic header designations.
2.3.2. The Difference Between render and redirect
Sometimes inexperienced developers conceive of redirect_to as a sort of goto command, moving execution from one place to another in your Rails code. This is not correct. Your code stops running and waits for a new request for the browser. It just happens that you've told the browser what request it should make next, by sending back a HTTP 302 status code.
Consider these actions to see the difference:
def index @books = Book.find(:all) end def show @book = Book.find(params[:id]) if @book.nil? render :action => "index" and return end end
With the code in this form, there will be likely be a problem if the @book variable is nil. Remember, a render :action doesn't run any code in the target action, so nothing will set up the @books variable that the index view is presumably depending on. One way to fix this is to redirect instead of rendering:
def index @books = Book.find(:all) end def show @book = Book.find(params[:id]) if @book.nil? redirect_to :action => "index" and return end end
With this code, the browser will make a fresh request for the index page, the code in the index method will run, and all will be well.
2.4. Using head To Build Header-Only Responses
The head method exists to let you send back responses to the browser that have only headers. It provides a more obvious alternative to calling render :nothing. The head method takes one response, which is interpreted as a hash of header names and values. For example, you can return only an error header:
head :bad_request
Or you can use other HTTP headers to convey additional information:
head :created, :location => photo_path(@photo)
3. Structuring Layouts
When Rails renders a view as a response, it does so by combining the view with the current layout (using the rules for finding the current layout that were covered earlier in this guide). Within a layout, you have access to three tools for combining different bits of output to form the overall response:
-
Asset tags
-
yield and content_for
-
Partials
I'll discuss each of these in turn.
3.1. Asset Tags
Asset tags provide methods for generating HTML that links views to assets like images, javascript, stylesheets, and feeds. There are four types of include tag:
-
auto_discovery_link_tag
-
javascript_include_tag
-
stylesheet_link_tag
-
image_tag
You can use these tags in layouts or other views, although the tags other than image_tag are most commonly used in the  section of a layout.
| The asset tags do not verify the existence of the assets at the specified locations; they simply assume that you know what you're doing and generate the link. |
3.1.1. Linking to Feeds with auto_discovery_link_tag
The auto_discovery_link_tag helper builds HTML that most browsers and newsreaders can use to detect the presences of RSS or ATOM feeds. It takes the type of the link (:rss+ or :atom), a hash of options that are passed through to url_for, and a hash of options for the tag:
<%= auto_discovery_link_tag(:rss, {:action => "feed"}, {:title => "RSS Feed"}) %>
There are three tag options available for auto_discovery_link_tag:
-
:rel specifies the rel value in the link (defaults to "alternate")
-
:type specifies an explicit MIME type. Rails will generate an appropriate MIME type automatically
-
:title specifies the title of the link
3.1.2. Linking to Javascript Files with javascript_include_tag
The javascript_include_tag helper returns an HTML


Immediately after installation, Jenkins will allow anyone to run anything as user jenkins, which is bad. This page shows you how to set up basic security using the Configure Global Security page.
The Configure Global Security page has two sections in which you:
- Set the security realm to determine who is allowed access
- Set the authorization to determine what each user is allowed to do
Security Realm
First, establish the user authentication method. For smaller, more informal installations, you can use Jenkins' own user database. For enterprise installations, you will want to use your corporate service, which allows users to log in to Jenkins with their usual username and password.
Jenkins' Own User Database
This is the simplest authentication scheme--Jenkins maintains its own independent user database. People can sign up for their own accounts, and you as the administrator decide who can do what in Jenkins.
- Go to the Jenkins dashboard, usually http://_server_:8080 or http://_server_/jenkins:8080, where server is the host on which Jenkins is running
- Select Manage Jenkins, then Configure Global Security
- Click Enable Security. The page will expand to offer a choice of access control.
- Select Jenkins’ own user database
- Place a check mark next to Allow users to sign up
- Continue with Authorization, below. In particular, do not forget to press the Save button at the bottom of the page.
Active Directory On Linux Server
If Jenkins is running on a Windows server then it is better to install the Active Directory plugin.
On a Linux host you have an option to either use the Active Directory plugin or an LDAP based authentication. To configure the LDAP to work with Active Directory, provide the following:
Server |
mydomaincontroller.mycompnay.com:389 |
|---|---|
Root DN |
dc=mycompnay,dc=com |
User Search Filter |
sAMAccountName={0} |
Manager DN |
cn=mymanageruser,ou=users,ou=na,ou=mycompany,dc=mycompany,dc=com |
Manager Password |
***** |
Note that the correct Manager DN value can vary greatly depending on your Active Directory set up.
UNIX NIS
To set up Network Information System:
- Go to the Jenkins dashboard, usually http://_server_:8080 or http://_server_/jenkins:8080, where server is the host on which Jenkins is running
- Select Manage Jenkins, then Configure Global Security
- Click Enable Security. The page will expand to offer a choice of access control
- Select Unix user/group database#* Push the Test button (on the extreme right)
- If Success is displayed, everything is set up properly
- If not, follow the instructions to fix the problem and repeat
- If you still do not succeed, push the Advanced button and specify Service Name sshd and repeat
- Continue with Authorization, below. In particular, do not forget to press the Save button at the bottom of the page.
LDAP
See LDAP Plugin. Then continue with Authorization, below. In particular, do not forget to press the Save button at the bottom of the page.
Authorization
The Authorization section of the Configure Global Security page allows you to configure what users are allowed to do once authenticated.
Matrix-based Security
Matrix-based security offers the most precise control over user privileges.
- Select Matrix-based security as the Authorization
- Give the Anonymous user only Overall Read access
- In the text box below the matrix, type your user name (or the user name you plan to use when you register as a new Jenkins user) and click Add
- Give yourself full access by checking the entire row for your user name
- Repeat for other users who deserve full access. The configuration should look like the picture below:
- Click Save at the bottom of the page. You will be taken back to the top page. Now Jenkins is successfully secured.
- Restart Jenkins (service jenkins restart on Linux)
If you set up a service like NIS, Active Directory or LDAP, you can now log in to Jenkins using your network credentials. If you are using Jenkins' own user database, create a user account for yourself:
- Click the Login link at the top right portion of the page
- Choose Create an account
- Specify the user name you used in the above step, and fill in the rest
If everything works smoothly, you are now logged on as yourself with full permissions. If something goes wrong, follow this to reset the security setting.
TBD
More docs to come. Suggestions on what needs to be written are greatly appreciated.


{% include "cannlytics_website/components/heros/hero_banner.html" with
title='Checkout'
description="Get your Cannlytics loot now."
 You will also
receive first access to Cannlytics' data sets.
Cancel at any time.


--- layout: newsstory title: DENIED match: Yeltz 1 Stafford 1 ---
The mighty Yeltz are still looking for their first victory after Stafford Rangers earned a 1-1 draw with a late equaliser at The Grove on Monday night.
We took the lead just before half time through Jimmy Quiggan and looked like we were going to do it until they scored late on in the 85th minute. That leaves us with a disappointing three points from the first four games and in 16th place in the table. Looking at that table shows we've played the top two so maybe things aren't too bad, so let's keep positive.
Saturday takes us to Billericay in Essex where Chelmsford City play their home games, before Tamworth visit The Grove next Tuesday.
N.B. Doc has found the time to produce a new fixtures poster for September for all of you who are interested.
Halesowen Town: Clarke; Colwell, Burnham, Smith, Collins, Skidmore, Quiggin (Newall 84), Leadbeater (Ashby 67), Elmes, Taylor, Hines (Reece 10). Unused Subs: Spencer, Garvey
Stafford Rangers: Price; A. Gibson (Daniel 67), Carter (Lovatt 84), Barrow, McAughtrie, Robinson (Bott 75), Berks, Heath, Bailey, Davidson, R. Gibson. Unused Subs: Wilkes, Ward.
Referee: H. Singh (West Bromwich)Attendance: 736
Booked: Heath (41), Reece (70), Skidmore (84)
Sponsors' Man of the Match (Twenty Twenty Promotional Ltd): Richard Colwell
Halesowen seemed on course to hold on for a narrow morale-boosting first win until they conceded a late goal directly from another set piece.
Stafford made the livelier start with the impressive David Berks firing in a 4th minute low drive which was grabbed by goalkeeper Tim Clarke before Richard Colwell turned a 7th minute cross away with Rob Heath lurking free in space. Berks then made an excellent 13th minute run but his chip shot was collected by Clarke.
With both sides lacking inspiration in the final third of the field, Halesowen's first real effort came when Richard Leadbeater hit a 25-yard drive over the bar in the 19th minute following a knock down by Rob Elmes. Substitute Dominic Reece, replacing the injured Les Hines, hit a Jason Burnham free-kick just past the post six minutes later. An overhead kick from Collins was then just tipped away by goalkeeper Ryan Price from under the bar after Reece earned a 35th minute corner. Stafford's Daniel Davidson beat defender Neil Smith in the 40th minute to set up Robin Gibson but he curled his effort wide of the mark.
Halesowen took the lead a minute before the break when Reece worked well down the left wing and his cross to Elmes let in *b*JIMMY QUIGGIN*cb* to scoop the ball home from 8 yards out.
The home side never really looked like adding to their goal tally in the second half although Elmes flashed a corner from Mark Taylor over the bar in the 58th minute and Skidmore drove wide after 73 minutes. Jason Ashby came on as a substitute for his first outing of the season to replace the injured Leadbeater but it was Halesowen's defence that was kept increasingly busy as the game wore on. Berks produced a 25-yard shot which was turned away for a corner by Clarke in the 75th minute and Halesowen then desperately defended two corners despite introducing John Newall to bolster the defence.
Stafford eventually equalised five minutes from time when Skidmore needlessly conceded a free-kick on the edge of the penalty area and BERKS curled the free-kick directly past the suspect Halesowen defensive wall leaving goalkeeper Clarke standing.


Members
NATIVE_TRANSFORMERS
Pre-processor before serializing Scope Tree; this is needed to serialize more complex objects.
Methods
AstHook(scope, node)
Object that wraps a node in the AST produced by esprima used for instrumenting the code
Parameters:
| Name | Type | Description |
|---|---|---|
scope |
StaticScope | The lexical scope that the node belongs to |
node |
object | An AST node |
DummyPubsub()
Dummy Pubsub used for instrumenting code without connecting.
- does not extend Pubsub, this is a standalone object
- this object is created instead of actual Pubsub when user code is initialized via Code.run().
- when user code is executed via Code.run(), it has an IPC channel to the master process.
in that case, pubsub.publish is done by the master process, and the child process (this process) sends
the message to the master process.
RootScope()
Attach some functions that should be available only on the root scope.
intercepted native functions (e.g. setTimeout, console.log, etc.) are replaced with custom functions
StaticScope()
Static Scope object used during instrumentation.
It is used to keep track of lexical scope of various AST nodes


Thanks for coming to "Nodeschool: A Chapter in the Making".
A talk by Lydia Kats
Node Interactive Europe, September 2016
Watch the talk on Youtube.
Download the slides (pdf, 2.3MB).
Thanks for coming to "Nodeschool: A Chapter in the Making".
My name is Lydia, I'm @llkats everywhere online.
I’m a front-end developer at craigslist, a classified ads site in the US. so what is a front-end dev doing at a largely enterprise-focused node conference?
In my spare time, I’m a co-organizer at the San Francisco chapter of Nodeschool, and today I want to give you some background on NodeSchool’s origins, what it was like to start our local chapter and some challenges we’ve come across in the two years of running it, and some potential ways forward for the organization as a whole.
NodeSchool is a decentralized, open-source community. Its mission has two goals: to create high quality programming curricula and to host community learning events.
For some history, I listened to the NodeUp podcast episode 55, where Mikeal Rogers, Max Ogden, Jessica Lord, and Rod Vagg all talked NodeSchool for the whole episode.
NodeSchool started as a series of Node modules that people wrote in order to facilitate code workshops at a series of events in 2013.
James Halliday, who you might know better as substack, made the first workshopper called stream-adventure
to teach people about streams for NodeConf 2013. Rod Vagg liked that it was interactive and hands-on, and made the learnyounode
module for CampJS, a JavaScript conference in Australia. The idea caught on and levelmeup
was soon created as a way to teach LevelDB.
The NodeSchool modules were created to be taught at specific events or meetups, but it was immediately apparently that they could be reused again and again, or even followed by a person on their own.
After they had a few of these modules, Max Ogden was talking to another developer named Brian Brennan at NodeConf EUabout how to take the concept further. Max came up with the name “nodeschool”, and Brian bought the domain right away that night.
nodeschool.io is the central hub and homebase for nodeschool online.
Its goal: “grow the node community and teach people some fundamental skills” – Max
substack and Max did the initial frontend on the first nodeschool.io homepage, and Max said I should show a screenshot...
So here it is in glorious Internet Archive Wayback Machine vision: the old nodeschool homepage.
Max told me that in the early days of the site, "before chapters, it was mostly workshop authors adding their workshops to the website and people adding their nodeschool events to the google spreadsheet that rendered the map on the site.
A while later Jessica Lord helped Max redesign the current homepage.
Which is the current homepage that you see today.
As the organization grew, Max came up with the idea for ‘chapters’ as location-specific, recurring meetups, and he launched the chapters feature on the website.
With growth came complexity, and Mathias Buus, @mafintosh on GitHub, wrote a bot to automate tasks in the repo. Along the way lots of other people helped out Rod and Substack out with workshopper modules themselves, and still many others helped with the main nodeschool website. It was truly a group effort, and they helped create about 100 new chapters at least in the first year.
Max told me that they designed the repo so that each chapter is in control of its GitHub team and its GitHub pages site, so theres little to no bottlenecks or maintenance needed by the people who work on the core nodeschool.github.io domain. He said that giving each chapter control of their own website and presence under the NodeSchool GitHub organization was “the key thing that [he thought] made it work as a decentralized group that can grow quickly. one of the challenges [they] faced is… [their] work on internationalization in both the website and the workshoppers. Martin Heidegger really led the charge there working with NodeSchool Osaka” and you can see the variety of languages at the top of the site itself that someone can choose from. so it was truly global in its focus from the beginning.
Jessica also made the hexagon logo and made a template so that people could add their own location abbreviation to it and make stickers really easily and have swag for their attendees. Stickers are basically a necessity these days for tech meetups anyhow, so it was just another way to help organizers get their events all official and stuff.
In December 2014, Andrew Duquet, who was working at NerdWallet at the time, created the issue in the NodeSchool organizers repo. He actually had very little node experience when he first created the issue, which was really cool that he felt empowered to do that.
https://GitHub.com/nodeschool/organizers/issues/92
Max Ogden pinged some people he knew in the area to help; I was one of them, and happy to jump on board. My now co-organizer, Reza Akhavan, was also participating in the discussion.
As we got started, the documentation in the NodeSchool org and wiki were really helpful, and a bunch of people chimed in to give advice. As an initial website, I forked the NodeSchool Campinas site at the suggestion of Filipe Oliveira (@fmoliveira) and made a few tweaks and went live. Reza made the twitter account, and we created the initial logo from the logo builder that Nodeschool has online.
Here’s some proof of our first event! And since then, almost every picture of an active event that we’ve taken looks kinda like this – a bunch of people in a room, on computers, getting help from other people.
that’s sort of the entirety of the event. it’s a casual gathering where people work at their own pace on the nodeschool materials. if someone gets stuck, or has more questions, they can just raise a hand and a mentor comes by to offer assistance. self-paced, no-pressure, social learning.
We’ve been holding NodeSchool SF almost every month for two years now. and that sort of regularity comes with a lot of effort.
Having Mozilla as our monthly sponsor means less logistical overhead for us as organizers, as well as a consistent homebase for our attendees.
Reza also redesigned our homepage and our stickers. We thought about the identity we wanted for the chapter and eventually settled on the rainbow as the identifying color scheme, since San Francisco a history of supporting and accepting LGBTQ and all sorts of folks, and that sort of sense of welcoming acceptance is a core part of the chapter’s identity, we want everyone to come and feel welcome at our events.
To that end, we also reiterate information about our Code of Conduct policy at the beginning of each event, to underscore and inform our attendees that harassing or offensive behavior will not be tolerated, in order to foster a safe and comfortable learning environment.
Community of mentors: we have a steady pool of mentors in the area. There are a lot of repeat mentors, though I have to shout out Rich Trott, who’s a Node core contributor, he’s mentored with us at every single event since it started in February 2015 because he’s amazing. Experienced Node developers in the Bay Area offer the time they have to spare, whether it’s for one event or several. That sort of dependable community has been awesome to tap into.
Format innovation: we’ve also tried playing with our format, like offering other lessons; focused sessions where attendees are more formally guided by a leader, teaming up with nodebots, etc.
And of course, I couldn’t do any of this without my amazing co-organizer Reza, whose energy and ideas and steady work makes all of it possible, and I know that he leans on me for help and work in the same way. Spreading out the work of logistics and organization with a team you can depend upon is crucial for the success of a NodeSchool chapter.
It also helps if you get a cake that’s decorated the same as your sticker logo too. That cake was amazing.
NodeSchool is as much a space to network and build relationships as it is a place to learn how to code, to meet other people at your level, or learn how to help others and become a mentor.
Students learn how to teach – they become mentors in turn, if they’re interested. or they learn how to public speak and lead sessions. Attendees at SF have met people through whom they got jobs, not by being recruited, but by expanding their network. Face-to-face contact presents people with opportunities they can’t have any other way.
There are some growing pains, though NodeSchool has grown really well for three years now, so instead I’ve been thinking of these challenges more as…
...maintenance pains. Now that we’ve been running our meetup for two years, it’s a little easier for us at NodeSchool SF to look beyond our chapter and appraise the current landscape of NodeSchool as an organization.
Martin Heidegger’s post The missing hands at NodeSchool
Martin recently wrote a Medium post about ways NodeSchool can improve, including translation and overall organization structure. I have a little overlap in this next section, but I also encourage you to read his post about ways to pitch in with NodeSchool.
The three main challenges I want to highlight in running a NodeSchool meetup are that workshopper quality has degraded over time, that our learning materials have a high barrier to entry for true novices, and an overall lack of organization-level direction.
But before I jump in to outlining these challenges…
…I better back up and explain workshoppers in more detail.
This is the core learning material for NodeSchool: command-line modules that contain related lessons. This is a screenshot from learnyounode which teaches fundamental node concepts. It has kind of an old-timey CRT monitor DOS feel to it. The lessons range from I/O and async concepts to writing simple HTTP servers.
to complete a lesson, a student has to write code and then run it against the workshopper’s tests
if you don’t pass, you get an error message and output to look at and compare against the expected output. A lot of workshopper tests match on randomly generated strings to make sure that the transformation logic is correct.
and when you do pass, you get a nice green PASS message, and some workshoppers like learnyounode offer the “official” output so you can compare how you implemented your solution.
If you remember the screenshot of the very first nodeschool website, there were all of three workshoppers to choose from.
now there’s a few more than that, so many that eight are labeled as the “core” curriculum and the rest are electives on special topics like react, functional programming, promises, and WebGL. and with so many workshoppers has come a certain amount of quality degradation over time as maintainers get busy or move on to new projects, they may not have the time or capacity to triage issues or accept pull requests. some workshoppers, even core curriculum ones, have dozens of open PRs and issues. we even tried having a couple of mentor hack nights in SF, but the problems with that approach were that it was difficult to know where to get started, and that even if the group created a few PRs for a workshopper, there wasn’t any faith that they would actually get merged.
another challenge we face is that it can be fairly difficult to even get going with these learning materials, especially as a very fresh beginner. you need to have an IDE or text editor of some sort set up and you have to figure out how to execute commands on the terminal. if you have newly installed node, you might get the EACCESS error when you try to install a workshopper module globally. these are difficulties that mentors are great at assisting with, but it remains a point of friction for beginning programmers.
and finally, there doesn’t feel like there’s an overarching goal or direction for the event or the organization. though we’re a global organization, chapters still feel fairly siloed from each other.
on the one hand, this lets people mold it into what fits the needs of their community
on the other, it can feel amorphous for new chapters to start or continue; there’s a lack of direction for improvement; difficult to understand the needs not only of attendees, but of organizers and mentors, the people who run nodeschool
so, with all that said about some of the maintenance pains we face, how do we try to fix some of these challenges?
I think that some of the answers lie in giving more power and merge permissions to NodeSchool contributors, in providing alternate methods to access the learning materials, and picking a few organization goals for people to work towards.
first, we should empower contributors by moving workshoppers to an organization where NodeSchool members have permission merge PRs I think that, at the very least, the eight core workshoppers should be hosted or forked into a location that nodeschool contributors can actively maintain them. Once people are confident their pull requests can get merged, I think that we’ll have a lot more volunteers for updating content. this way, discussion and organization around priorities and standards or quality for each workshopper can also happen in their respective repositories. we could also define over-arching standards, like a consistent code style for every workshopper.
there are tools out there to potentially make workshoppers more accessible.
git-it
workshopper by Jessica Lord
Jessica’s first version of the git-it
workshopper, which teaches how to use git and GitHub, was a module in the terminal. But she recently revamped it as an electron module, where the guide and exercises are all self-contained. The only other thing needed is a text editor. This interface can be a little more approachable for people
Maintain command-line modules for people who are comfortable using the terminal and already have their IDE set up but for people who are not as familiar, an environment like Cloud9 could be an all-in-one solution that avoids having to make students download modules, configure file permissions, or worry about where they are saving files. It’s definitely not the same as having a whole environment set up, or learning about that workflow holistically, but if a student’s goal is to learn some programming skills that day, it could ease the whole overhead of setup for that event. Additionally, if we wanted to be able to support people who can’t bring a laptop, it might ease the difficulty of having to borrow a computer. Cloud9 is definitely not a panacea, but it could be a useful tool in specific cases.
We recently surveyed NodeSchool SF attendees, and while I haven’t gotten a representative sample yet, there have already been some interesting suggestions for things to improve with our own events. as an organization, we could survey and measure needs and wants as well.
nodeschool is 100% volunteer-run. It’d be really helpful to break tasks down into things that people can feasibly take on in an evening or weekend, since we’re all busy folks with lives outside of work and nodeschool as well. once people are aware of the organization’s goals, once we can agree what to work on, I think that contributions will follow.
explore how other groups are teaching programming, their methods and motives, and see what we can learn from them. NodeTogether and Railsbridge are two groups that spring to mind.
and these are just a few ideas. I know a lot of really smart people have other ideas too - we need to bring them all together somehow.
in all, I’ve come to realize that the effort you need to start something is different than the effort you need to maintain it
once you have the content and the organization together, what’s next? I think that’s the question we’re asking ourselves as we continue working with NodeSchool events.
 Teach someone to fish, and you feed them for a lifetime.” What I’ve learned from NodeSchool is that if you give community a framework for education, they’ll go out and teach the world. That’s a remarkable fact about the JavaScript community. We will to continue to think of ways to maintain and grow the utility of NodeSchool, which is already off to such a great start. I feel lucky to be a part of it.
Just a few quick shoutouts to people who have helped me with this talk, with content, information, and advice
James Halliday (@substack), Rod Vagg (@rvagg), Jessica Lord (@jllord), Martin Heidegger @leichtgewicht, Mathias Buus (@mafintosh), Reza Akhavan (@jedireza), Andrew Duquet (@duquet), Filipe Oliveira (@fmoliveira), and all NodeSchool organizers, contributors, mentors, and attendees worldwide
And to a few exceptional people who have made NodeSchool and NodeSchool SF what it is today
and to all of you for listening, I hope you take a look at what we’re doing over at NodeSchool and help us grow the Node community by teaching the world. Thanks!


CPSSDChat
account_circle
E-mail
lock
Password
Log in
CPSSD Chat
search
settings
input
group
Rooms
public
General
lock_outline
CPSSD1
lock_open
CPSSD2
group_add
New Room
person
People
lens
voy
lens
Terry
schedule
Ryan
not_interested
Mladen
smartphone
Conor


A property path is a possible route through a graph between two graph nodes. A trivial case if a property path of length exactly 1, which is a triple pattern.
A property path expression (or just 'path') is similar to a string regular expression but over properties, not characters. ARQ determines all matches of a path expression and binds subject or object as appropriate. Only one match is recorded - no duplicates for any given path expression, although is the path is used in a situation where it's initial points is already repeated in a pattern, then this duplication is preserved.
| Path | |
|---|---|
dc:title | rdfs:label |
Dublin Core title or an RDFS label. |
foaf:knows/foaf:name |
Name of people one "knows" steps away. |
foaf:knows/foaf:knows/foaf:name |
Name of people two "knows" steps away. |
In the description below, uri
is either a URI or a
prefixed name.
| Syntax Form | Matches |
|---|---|
uri |
A URI or a prefixed name. A path of length one. |
^elt |
Reverse path (object to subject). |
(elt) |
A group path elt , brackets control precedence. |
elt1 / elt2 |
A sequence path of elt1 , followed by elt2 |
elt1 ^ elt2 |
Shorthand for elt1 / ^elt2 , that is elt1
followed by reverse elt2 . |
elt1 | elt2 |
A alternative path of elt1 , or elt2 (all
possibilities are tried) |
elt* |
A path of zero or more occurrences of elt . |
elt+ |
A path of one or more occurrences of elt . |
elt? |
A path of zero or one elt . |
elt{n,m} |
A path between n and m occurrences of elt . |
elt{n} |
Exactly n occurrences of elt .
A fixed length path. |
elt{n,} |
n or more occurrences of elt . |
A zero occurrence of an path element always matches.
Precedence:
*
, ?
, +
and {n,m}
/
and ^|
Precedence is left-to-right within groups.
Paths are "simple" if they involve only operators / (sequence), ^ (reverse, unary or binary) and the form {n}, for some single integer n. Such paths are fixed length. They are translated to triple patterns by the query compiler and do not require special path-evaluation at runtime.
A path of just a URI is still a single triple pattern.
A path is "complex" if it involves one or more of the operators *,?, + and {}. Such paths require special evaluation and provide expressivity outside of strict SPARQL because paths can be of variable length. When used with models backed by SQL databases, complex path expressions may take some time.
A path of length zero connects a graph node to itself.
Cycles in paths are possible and are handled.
Paths do not need to be anchored at one end of the other, although this can lead to large numbers of result because the whole graph is searched.
Property functions in paths are only available for simple paths.
This involves is syntactic extension and is available if the query is parsed
with language Syntax.syntaxARQ
.
Paths can be directly included in the query in the property position of a triple pattern:
PREFIX : <http://example/> PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> # Find the types of :x, following subClassOf SELECT * { :x rdf:type/rdfs:subClassOf* ?t }
Find the name of any people that Alice knows.
{ ?x foaf:mbox <mailto:alice@example> . ?x foaf:knows/foaf:name ?name . }
Find the names of people 2 "foaf:knows
" links away.
{ ?x foaf:mbox <mailto:alice@example> . ?x foaf:knows/foaf:knows/foaf:name ?name . }
This is the same as the strict SPARQL query:
{ ?x foaf:mbox <mailto:alice@example> . ?x foaf:knows [ foaf:knows [ foaf:name ?name ]]. }
or, with explicit variables:
{ ?x foaf:mbox <mailto:alice@example> . ?x foaf:knows ?a1 . ?a1 foaf:knows ?a2 . ?a2 foaf:name ?name . }
Because someone Alice knows may well know Alice, the example above may include Alice herself. This could be avoided with:
{ ?x foaf:mbox <mailto:alice@example> . ?x foaf:knows/foaf:knows ?y . FILTER ( ?x != ?y ) ?y foaf:name ?name }
These two are the same query: the second is just reversing the property direction which swaps the roles of subject and object.
{ ?x foaf:mbox <mailto:alice@example> }
{ <mailto:alice@example> ^foaf:mbox ?x }
Mutual foaf:knows
relationships: ?x
knows someone
who knows ?x
{ ?x foaf:knows^foaf:knows ?x . }
Find the names of all the people can be reached from Alice by
foaf:knows
:
{ ?x foaf:mbox <mailto:alice@example> . ?x foaf:knows+/foaf:name ?name . }
Again, because of cycles in foaf:knows
relationships, it is
likely to include Alice herself.
Some forms of limited inference are possible as well. For example: all types and supertypes of a resource:
{ <http://example/> rdf:type/rdfs:subClassOf* ?type }
All resources and all their inferred types:
{ ?x rdf:type/rdfs:subClassOf* ?type }
A path can parsed, then installed as a property function to be referred to by URI. This way, when the URI is used in the predicate location in a triple pattern, the path expression is evaluated.
Path path = ... String uri = ... PathLib.install(uri, path) ;
For example:
Path path = PathParser.parse("rdf:type/rdfs:subClassOf*", PrefixMapping.Standard) ; String uri = "http://example/ns#myType" ; PathLib.install(uri, path) ;
and the SPARQL query:
PREFIX : <http://example/> PREFIX ns: <http://example/ns#> # Find the types of :x, following subClassOf SELECT * { :x ns:myType ?t}
This also works with if an existing property is redefined (a URI in a path
expression is not interpreted as a property function) so, for example, rdf:type
can be redefined as a path that also considers RDFS sub -class relationships.
The path is a complex path so the property function for rdf:type
is not triggered.
Path path = PathParser.parse("rdf:type/rdfs:subClassOf*", PrefixMapping.Standard) ; PathLib.install(RDF.type.getURI(), path) ;


HOMEPAGE
» Here you can find most popular tags and recent activities.
Local search
Search on network
Search by tags
Tag Cloud
Activity Stream


Papel
Home
Contact Us
Sign Up / Login
sign in
sign up
Login
Forgot your password?
Create account
By pressing the Create Account button, you agree to our
terms of service
.


Works where you work, on almost every OS.
Deploy one lock, or many locks, the only barrier is file descriptors.
QA locks. Production locks. Whatever locks.
Locks for devs, locks for ops.


Users can refund themselves during a grace period, then request administrator-approved refunds.
No refund requests have occured yet.


Strike credit at UNBC
by The Canadian PressThe University of Northern British Columbia says it will provide a non-refundable financial credit to all students who have been out of class since a strike by faculty began earlier this month.
A post on the university's website says the value of the credit depends on the length of the strike and that be determined once a new contract is reached with about 180 faculty at the Prince George-based university.
The notice informs students that if classes resume on or before next Tuesday, the semester will be extended to Dec. 14 and final exams will be cancelled or delayed, but if job action continues past Dec. 3, the semester will pick up in January, delaying the new term.
Wages are a key issue in the strike involving professors and other faculty who walked out Nov. 7, after being without a contract since June.
Talks stalled over the weekend,but a social media post issued by the union says it remains ready to negotiate this week.
About 3,500 students in Prince George and at satellite campuses in Terrace, Prince Rupert, Quesnel and Fort St. John are affected by the dispute, the second in four years at the university after a two-week strike ended in March 2015.


The Joint Liaison Group (JLG) between the secretariats of the Convention on Biological Diversity (CBD), the United Nations Convention to Combat Desertification (UNCCD) and the United Nations Framework Convention on Climate Change (UNFCCC) was established with the aim of enhancing coordination between the three conventions including cooperation concerning the links between climate change, biodiversity and desertification. All three secretariats currently collaborate through information sharing and outreach, including the development of common messages. Further collaboration focuses on ensuring that Parties are kept informed of relevant initiatives in other conventions.
The CBD is an international treaty which entered into force on 29 December 1993. It has 3 main objectives:
Established in 1994, UNCCD is the sole legally binding international agreement linking environment and development to sustainable land management. The Convention addresses specifically the arid, semi-arid and dry sub-humid areas, known as the drylands, where some of the most vulnerable ecosystems and peoples can be found
The UNFCCC entered into force on 21 March 1994. Today, it has near-universal membership, with 195 Parties. Preventing “dangerous” human interference with the climate system is the ultimate aim of the UNFCCC..


Listview Autodivider Linkbar
This demo shows the linkbar extension that adds a fixed positioned bar on the right of the screen that makes it easy to anchor down to a specific part of a listview. View the source to see how it works.
Open demoThis demo shows the linkbar extension that adds a fixed positioned bar on the right of the screen that makes it easy to anchor down to a specific part of a listview. View the source to see how it works.
Open demo


AWS credentials for accessing AWS CodeBuild.
If you configured an IAM role, ensure that it includes the following policy statements
(where {PROJECTNAME}
is replaced with the name of your project):
[
{
"Effect": "Allow",
"Resource": "*",
"Action": ["codebuild:ListProjects"]
}
{
"Effect": "Allow",
"Resource": "arn:aws:codebuild:*:*:project/{PROJECTNAME}",
"Action": ["codebuild:StartBuild", "codebuild:StopBuild"]
}
]


1784- A team of explorer’s sets off to the pole, they find something in the ice, but before they can get back they go missing mysteriously. Nowadays- Another team of explorer’s sets off for the pole, there mission is to collect surface samples from the most northerly point on Planet Kerbin.
⇥They land their plane just outside of an arctic village, the inhabitants tell them not to go any further or the gods will punish them for their sins. They decide to travel by car and set off forgetting the advice the tribe had given them. A large alien structure emerges through the snow storm, it towers several hundred metres in the sky. They report the findings back to base.
⇥2 Years after discovery- The site is awash with scientists and structures researching the alien structure. The structure activates and the scientists find out that it is sending a signal to another planet. A board meeting is held between all countries of Kerbin determining what to do. They set up Project Arctic, a one way mission to the planet to investigate the receiver. Scene finishes with a image of Project Arctic badge, which fades into the next scene with a badge on the side of a craft.
⇥4 Years after discovery- The ship is finished in space and has had final checks and the crew docked. The scientist is the same Kerbal who discovered the structure, he is the main character. The crew goes into cryostasis and the ship jumps to the alien location.
⇥8 Years after discovery- The ship arrives at the planet and the crew come out of cryostasis, a shuttle is launched and lands on the planets surface. The surface resembles LV 426 in looks and is my inspiration. The crew use rovers to travel closer to the receiver. They come to a ridge and peak over revealing a huge alien structure with bio domes and other technologies. The crew enter the structure and find it is counting down. They investigate what it is doing and who built it. Before long the team members begin to disappear one by one, the survivors eventually find their way out and take off in the shuttle.
⇥It re-docks with the mothership and finds that whatever was down there with them has managed to come aboard. After desperately trying to find out what the countdown is for, they discover that it is until the receiver sends a message for Kerbin structure to self destruct killing the planet. The crew now down to one decides to ram the receiver resulting in a spectacular explosion. The film ends with the camera pulling back to reveal thousands of receivers.


Previous
Next
WANNA TAKE A SNEAK PEAK OF MY BLOG:
WANNA SEE MY RECENT UPLOAD :
Top


{% extends 'layout.html' %} {% block controllers %} {% if isOwner %} {% if not isDone %} {% endif %} {% else %} {% endif %} {% endblock %} {% block content %}
This cannot be undone. All data related to the board, including invites, etc, will not be available.
This cannot be undone.
You will not be able to view or interact with the board unless the creator re-invites you.


WITNESS LIST
State Affairs Committee
October 24, 2012 - 10:00 AM
Public Utility Regulation Interim Charge
On:
Harder, Chuck (CenterPoint Energy, Inc. Natural Gas Operations)
Peacock, Bill (Texas Public Policy Foundation)
Resource Adequacy Interim Charge
On:
Counihan, Richard (EnerNOC, Inc. and The Texas Demand Response Coalition)
Doggett, Trip (ERCOT)
Fainter Jr, John W (Association of Electric Companies of Texas, Inc.)
Henry, Sam (GDF Suez North America)
Hill, Thad (Calpine Corporation)
Nelson, Donna (PUC of TX)
Newell, Samuel (The Brattle Group)
Oldham, Phillip (Texas Association of Manufacturers)
Power, David (Public Citizen)
Schwirtz, Mark (Golden Spread Electric Coop + Texas Electric Cooperatives)
1


(#) Assertions with Side Effects
!!! WARNING: Assertions with Side Effects
This is a warning.
Id
: `AssertionSideEffect`
Summary
: Assertions with Side Effects
Severity
: Warning
Category
: Performance
Platform
: Any
Vendor
: Android Open Source Project
Feedback
: https://issuetracker.google.com/issues/new?component=192708
Affects
: Kotlin and Java files
Editing
: This check runs on the fly in the IDE editor
Implementation
: [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-checks/src/main/java/com/android/tools/lint/checks/AssertDetector.kt)
Tests
: [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-tests/src/test/java/com/android/tools/lint/checks/AssertDetectorTest.kt)
Copyright Year
: 2014
Assertion conditions can have side effects. This is risky because the
behavior depends on whether assertions are on or off. This is usually
not intentional, and can lead to bugs where the production version
differs from the version tested during development.
Generally, you'll want to perform the operation with the side effect
before the assertion, and then assert that the result was what you
expected.
(##) Example
Here is an example of lint warnings produced by this check:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text
src/test.kt:4:Warning: Assertion condition has a side effect: i++
[AssertionSideEffect]
assert(i++ < 5) // WARN 1
---
src/test.kt:5:Warning: Assertion condition has a side effect: x++
[AssertionSideEffect]
assert(method1() > 5) // WARN 2
---------
src/test.kt:6:Warning: Assertion condition has a side effect: x++
[AssertionSideEffect]
assert(method2() > 5) // WARN 3
---------
src/test.kt:7:Warning: Assertion condition has a side effect: x = 0
[AssertionSideEffect]
assert(method3()) // WARN 4
---------
src/test.kt:9:Warning: Assertion condition has a side effect: delete()
[AssertionSideEffect]
assert(file.delete()) // WARN 5
-------------
src/test.kt:10:Warning: Assertion condition has a side effect: mkdirs()
[AssertionSideEffect]
assert(file.mkdirs()) // WARN 6
-------------
src/test.kt:11:Warning: Assertion condition has a side effect:
add("test") [AssertionSideEffect]
assert(list.add("test")) // WARN 7
----------------
src/test.kt:12:Warning: Assertion condition has a side effect:
setExecutable(true) [AssertionSideEffect]
assert(file.setExecutable(true)) // WARN 8
------------------------
src/test.kt:14:Warning: Assertion condition has a side effect: x++
[AssertionSideEffect]
assert(method5()) // WARN 9
---------
src/test.kt:15:Warning: Assertion condition has a side effect: x++
[AssertionSideEffect]
assert(method6()) // WARN 10
---------
src/test.kt:16:Warning: Assertion condition has a side effect: x++
[AssertionSideEffect]
assert(method7()) // WARN 11
---------
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Here is the source file referenced above:
`src/test.kt`:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~kotlin linenumbers
var x: Int = 0
fun test(file: java.io.File, list: java.util.List


Performs binary and multiclass boosting in maximum-margin, sparse, smooth and normal settings as described in "A Boosting Framework on Grounds of Online Learning" by T. Naghibi and B. Pfister, (2014). For further information regarding the algorithms, please refer to http://arxiv.org/abs/1409.7202
| Version: | 1.0-0 |
| Depends: | R (≥ 2.10), rpart, C50 |
| Published: | 2014-11-25 |
| Author: | Tofigh Naghibi |
| Maintainer: | Tofigh Naghibi <tofigh at gmail.com> |
| License: | GPL-2 | GPL-3 [expanded from: GPL (≥ 2)] |
| NeedsCompilation: | no |
| CRAN checks: | maboost results |
| Reference manual: | maboost.pdf |
| Package source: | maboost_1.0-0.tar.gz |
| Windows binaries: | r-devel: maboost_1.0-0.zip, r-release: maboost_1.0-0.zip, r-oldrel: maboost_1.0-0.zip |
| OS X binaries: | r-release: maboost_1.0-0.tgz, r-oldrel: maboost_1.0-0.tgz |
Please use the canonical form https://CRAN.R-project.org/package=maboost to link to this page.


JXTA Technology Documents
The following technical documents are available on JXTA(TM) technology.
Additional technical documents may be found in each of the JXTA community hosted projects.
(NOTE: Many of these documents are in PDF. Click here if you need to download the Acrobat Reader.)
Categories
|
Documentation Quick Links
|
- JXTA Technology: Creating Connected
Communities Rev. February 2005
This document gives an overview of the JXTA technology. It includes information
on Peer-to-Peer (P2P) computing, the history of Project JXTA, the benefits
of JXTA technology, and examples of what companies are doing with JXTA
technology today.
- Project JXTA:
An Open, Innovative Collaboration
Interest in peer-to-peer (P2P) technology is growing rapidly, as evidenced
by the popularity of services like Napster, Gnutella, and SETI@home. Seeing
the potential of P2P computing to enable access to a broader, deeper Web,
Sun started a small research effort called Project JXTA. This paper examines
the evolution of Internet use, the expanded access that the technology promises,
and Sun's efforts to advance network computing through Project JXTA. Sun's
efforts in offering JXTA technology through the open source model is described.
-
Project
JXTA 2.0 Super-Peer Virtual Network
The JXTA 2.0 implementation introduces a number of new features for improving
overall functionality, performance, and scalability of the JXTA network.
- Project
JXTA: A Technology Overview
Project JXTA is an effort to develop a network programming and computing
platform to solve a number of problems in modern distributed computing. This
paper explains the basic elements of JXTA technology, including terminology,
protocols and considerations for security. The Project JXTA release 1.0 implementation
from Sun Microsystems, Inc. is described, as is the JXTA Shell applications
and prospects for future development.
- JXTA
for J2METM - Extending the Reach of Wireless With JXTA Technology:
Peer-to-peer (P2P) computing readily lends itself to the more dynamic environments
of wireless devices. Characterized by their ability to create, join, and
interact with peer groups, and to post advertisements to offer and solicit
resources, P2P applications can dynamically find what they need - an approach
more suited to the wireless lifestyle. Project JXTA for J2ME is the response
of the JXTA developer community to this need. Designed to offer a rich programming
environment for creating applications using the P2P computing model, JXTA
for J2ME technology promises to accelerate development for those wishing
to participate in the wireless applications marketplace.
- Framework for
Peer-to-Peer Distributed Computing in a Heterogeneous, Decentralized Environment
This paper presents a framework for large-scale computations for problems
that feature coarse-grained parallelization. The components of this framework
are based on Java, which allows for a wide variety of platforms and components,
and peer-to-peer communication is provided through the JXTA protocols, which
allow for a dynamic and decentralized organization of computational resources.
- JXTA:
A Network Programming Environment
L. Gong. JXTA: A network programming environment. IEEE Internet Computing,
v. 5, pp. 88-95, 2001
JXTA technology provides a network programming and computing platform designed
to solve a number of problems in modern distributed computing, especially
in the burgeoning realm of peer-to-peer (p2p) computing. The objective of
Project JXTA include interoperability among otherwise competing p2p applications,
platform and programming language independence, and ubiquity of deployment.
At its core, JXTA is a protocol suite focusing on mechanisms instead of policy,
so that application developers have maximum freedom to innovate and offer
competitive solutions.
- Project
JXTA-C: Enabling a Web of Things
This paper presents an up-to-date overview of the JXTA protocols and describes
the latest implementation of the JXTA protocols in the "C" programming language.
Included are discussions of the overall architecture and trade-offs made
to allow the JXTA-C implementation to run on a wide range of devices including
supercomputers, servers, PCs and memory-constrainted embedded devices.
- Project JXTA
Technology Datasheet
This two page datasheet was created by Sun Microsystems, Inc. to give a general,
high-level overview of JXTA technology.
- UPDATED Jan 2005! Project JXTA: JavaTM Programmers Guide
and Companion Tutorial
Programs
The JXTA protocols are independent of any programming language, and multiple
implementations (called bindings in Project JXTA) exist for different environments.
This document specifically discusses the Project JXTA binding on the JavaTM
2 Platform, Standard Edition software (J2SETM). This document
is intended for software developers who would like to write and deploy P2P
services and applications using the Java programming language and JXTA technology.
It matches the Project JXTA J2SE 2.3.x platform binding stable release. Click here for a quick reference to the Programmers
Guide glossary.
- Project JXTA J2SE Implementation Source Code Documentation (JavaDoc)
- Project JXTA: Protocol Specification V2.0 February
2003
This document describes in detail the architecture and components of Project
JXTA technology. The key elements and their role in supporting peer-to-peer
computing environments are discussed. These include peers, advertisements,
messages, pipes, and protocols. Specifications for the advertisements and
protocols defined in the 2.0 Release are described including functions, XML
definitions, and as appropriate, data structures.
- Project JXTA:
Technical Shell Overview April 2001
In addition to being an application that illustrates the use of JXTA Technology,
the JXTA Shell is a useful tool that can help end users understand the value
of Peer-to-Peer computing. The JXTA Shell permits interactive access the JXTA
platform building blocks through a simple, text based interface. This document
describes the syntax and functionality of each of the JXTA shell commands,
and also discusses the open framework that allows developers to add additional
commands.
- Project JXTA:
Getting Started (using the Project JXTA Shell) April 2001
Getting hands on JXTA technology is simple. With the release of Version 1.0,
users running the Solaris Operating Environment, Linux, or Microsoft Windows
can freely download binaries and source, along a prototype application, the
JXTA Shell. By experimenting with the JXTA Shell, users can quickly grasp
the power and potential of peer-to-peer computing. This document creates a
fast track for users and developers that are curious about JXTA technology
and want to know more.
- A Loosely-Consistent DHT Rendezvous Walker
March 2003
Bernard Traversat, Mohamed Abdelaziz, Eric Pouyoul: Sun Microsystems,
Inc.
The following paper describes a loosely-consistent DHT walker approach for
searching advertisements and routing queries in the JXTA rendezvous network.
The loosely-consistent DHT walker uses a hybrid approach that combines the
use of a DHT to index and locate contents, with a limited range walker to
resolve inconsistency of the DHT within the dynamic rendezvous network. This
proposed DHT approach does not require maintaining consistency across the
rendezvous network, a stable super-peer infrastructure, and is well adapted
to ad hoc P2P networks with high peer churn rate.


Revolutionary, Safe, and Sustainable Insect Monitoring and Control
The SolaRid ICD (insect control device) eliminates the need for daily in-field monitoring. Data is provided to IPM professionals 24 hours per day, 7 days a week.
Through groundbreaking developments in the worlds of Artificial Intelligence, the AIIoT (Agricultural-Industrial Internet of Things), and precision agricultural management, SolaRid allows farmers to easily and efficiently manage fields, crops, and insects, all easily accessible from any device with internet access.


Functions to be used in fabfiles and other non-core code, such as run()/sudo().
Download one or more files from a remote host.
get returns an iterable containing the absolute paths to all local files downloaded, which will be empty if local_path was a StringIO object (see below for more on using StringIO). This object will also exhibit a .failed attribute containing any remote file paths which failed to download, and a .succeeded attribute equivalent to not .failed.
remote_path is the remote file or directory path to download, which may contain shell glob syntax, e.g. "/var/log/apache2/*.log", and will have tildes replaced by the remote home directory. Relative paths will be considered relative to the remote user’s home directory, or the current remote working directory as manipulated by cd. If the remote path points to a directory, that directory will be downloaded recursively.
local_path is the local file path where the downloaded file or files will be stored. If relative, it will honor the local current working directory as manipulated by lcd. It may be interpolated, using standard Python dict-based interpolation, with the following variables:
ノート
When remote_path is an absolute directory path, only the inner directories will be recreated locally and passed into the above variables. So for example, get('/var/log', '%(path)s') would start writing out files like apache2/access.log, postgresql/8.4/postgresql.log, etc, in the local working directory. It would not write out e.g. var/log/apache2/access.log.
Additionally, when downloading a single file, %(dirname)s and %(path)s do not make as much sense and will be empty and equivalent to %(basename)s, respectively. Thus a call like get('/var/log/apache2/access.log', '%(path)s') will save a local file named access.log, not var/log/apache2/access.log.
This behavior is intended to be consistent with the command-line scp program.
If left blank, local_path defaults to "%(host)s/%(path)s" in order to be safe for multi-host invocations.
警告
If your local_path argument does not contain %(host)s and your get call runs against multiple hosts, your local files will be overwritten on each successive run!
If local_path does not make use of the above variables (i.e. if it is a simple, explicit file path) it will act similar to scp or cp, overwriting pre-existing files if necessary, downloading into a directory if given (e.g. get('/path/to/remote_file.txt', 'local_directory') will create local_directory/remote_file.txt) and so forth.
local_path may alternately be a file-like object, such as the result of open('path', 'w') or a StringIO instance.
ノート
Attempting to get a directory into a file-like object is not valid and will result in an error.
ノート
This function will use seek and tell to overwrite the entire contents of the file-like object, in order to be consistent with the behavior of put (which also considers the entire file). However, unlike put, the file pointer will not be restored to its previous location, as that doesn’t make as much sense here and/or may not even be possible.
ノート
If a file-like object such as StringIO has a name attribute, that will be used in Fabric’s printed output instead of the default <file obj>
バージョン 1.0 で変更: Now honors the remote working directory as manipulated by cd, and the local working directory as manipulated by lcd.
バージョン 1.0 で変更: Now allows file-like objects in the local_path argument.
バージョン 1.0 で変更: local_path may now contain interpolated path- and host-related variables.
バージョン 1.0 で変更: Directories may be specified in the remote_path argument and will trigger recursive downloads.
バージョン 1.0 で変更: Return value is now an iterable of downloaded local file paths, which also exhibits the .failed and .succeeded attributes.
バージョン 1.5 で変更: Allow a name attribute on file-like objects for log output
Run a command on the local system.
local is simply a convenience wrapper around the use of the builtin Python subprocess module with shell=True activated. If you need to do anything special, consider using the subprocess module directly.
shell is passed directly to subprocess.Popen‘s execute argument (which determines the local shell to use.) As per the linked documentation, on Unix the default behavior is to use /bin/sh, so this option is useful for setting that value to e.g. /bin/bash.
local is not currently capable of simultaneously printing and capturing output, as run/sudo do. The capture kwarg allows you to switch between printing and capturing as necessary, and defaults to False.
When capture=False, the local subprocess’ stdout and stderr streams are hooked up directly to your terminal, though you may use the global output controls output.stdout and output.stderr to hide one or both if desired. In this mode, the return value’s stdout/stderr values are always empty.
When capture=True, you will not see any output from the subprocess in your terminal, but the return value will contain the captured stdout/stderr.
In either case, as with run and sudo, this return value exhibits the return_code, stderr, failed and succeeded attributes. See run for details.
local will honor the lcd context manager, allowing you to control its current working directory independently of the remote end (which honors cd).
バージョン 1.0 で変更: Added the succeeded and stderr attributes.
バージョン 1.0 で変更: Now honors the lcd context manager.
バージョン 1.0 で変更: Changed the default value of capture from True to False.
Invoke a fully interactive shell on the remote end.
If command is given, it will be sent down the pipe before handing control over to the invoking user.
This function is most useful for when you need to interact with a heavily shell-based command or series of commands, such as when debugging or when fully interactive recovery is required upon remote program failure.
It should be considered an easy way to work an interactive shell session into the middle of a Fabric script and is not a drop-in replacement for run, which is also capable of interacting with the remote end (albeit only while its given command is executing) and has much stronger programmatic abilities such as error handling and stdout/stderr capture.
Specifically, open_shell provides a better interactive experience than run, but use of a full remote shell prevents Fabric from determining whether programs run within the shell have failed, and pollutes the stdout/stderr stream with shell output such as login banners, prompts and echoed stdin.
Thus, this function does not have a return value and will not trigger Fabric’s failure handling if any remote programs result in errors.
バージョン 1.0 で追加.
Prompt user with text and return the input (like raw_input).
A single space character will be appended for convenience, but nothing else. Thus, you may want to end your prompt text with a question mark or a colon, e.g. prompt("What hostname?").
If key is given, the user’s input will be stored as env.<key> in addition to being returned by prompt. If the key already existed in env, its value will be overwritten and a warning printed to the user.
If default is given, it is displayed in square brackets and used if the user enters nothing (i.e. presses Enter without entering any text). default defaults to the empty string. If non-empty, a space will be appended, so that a call such as prompt("What hostname?", default="foo") would result in a prompt of What hostname? [foo] (with a trailing space after the [foo].)
The optional keyword argument validate may be a callable or a string:
Either way, prompt will re-prompt until validation passes (or the user hits Ctrl-C).
ノート
prompt honors env.abort_on_prompts and will call abort instead of prompting if that flag is set to True. If you want to block on user input regardless, try wrapping with settings.
Examples:
# Simplest form:
environment = prompt('Please specify target environment: ')
# With default, and storing as env.dish:
prompt('Specify favorite dish: ', 'dish', default='spam & eggs')
# With validation, i.e. requiring integer input:
prompt('Please specify process nice level: ', key='nice', validate=int)
# With validation against a regular expression:
release = prompt('Please supply a release name',
validate=r'^\w+-\d+(\.\d+)?$')
# Prompt regardless of the global abort-on-prompts setting:
with settings(abort_on_prompts=False):
prompt('I seriously need an answer on this! ')
Upload one or more files to a remote host.
put returns an iterable containing the absolute file paths of all remote files uploaded. This iterable also exhibits a .failed attribute containing any local file paths which failed to upload (and may thus be used as a boolean test.) You may also check .succeeded which is equivalent to not .failed.
local_path may be a relative or absolute local file or directory path, and may contain shell-style wildcards, as understood by the Python glob module (give use_glob=False to disable this behavior). Tilde expansion (as implemented by os.path.expanduser) is also performed.
local_path may alternately be a file-like object, such as the result of open('path') or a StringIO instance.
ノート
In this case, put will attempt to read the entire contents of the file-like object by rewinding it using seek (and will use tell afterwards to preserve the previous file position).
remote_path may also be a relative or absolute location, but applied to the remote host. Relative paths are relative to the remote user’s home directory, but tilde expansion (e.g. ~/.ssh/) will also be performed if necessary.
An empty string, in either path argument, will be replaced by the appropriate end’s current working directory.
While the SFTP protocol (which put uses) has no direct ability to upload files to locations not owned by the connecting user, you may specify use_sudo=True to work around this. When set, this setting causes put to upload the local files to a temporary location on the remote end (defaults to remote user’s $HOME; this may be overridden via temp_dir), and then use sudo to move them to remote_path.
In some use cases, it is desirable to force a newly uploaded file to match the mode of its local counterpart (such as when uploading executable scripts). To do this, specify mirror_local_mode=True.
Alternately, you may use the mode kwarg to specify an exact mode, in the same vein as os.chmod or the Unix chmod command.
put will honor cd, so relative values in remote_path will be prepended by the current remote working directory, if applicable. Thus, for example, the below snippet would attempt to upload to /tmp/files/test.txt instead of ~/files/test.txt:
with cd('/tmp'):
put('/path/to/local/test.txt', 'files')
Use of lcd will affect local_path in the same manner.
Examples:
put('bin/project.zip', '/tmp/project.zip')
put('*.py', 'cgi-bin/')
put('index.html', 'index.html', mode=0755)
ノート
If a file-like object such as StringIO has a name attribute, that will be used in Fabric’s printed output instead of the default <file obj>
バージョン 1.0 で変更: Now honors the remote working directory as manipulated by cd, and the local working directory as manipulated by lcd.
バージョン 1.0 で変更: Now allows file-like objects in the local_path argument.
バージョン 1.0 で変更: Directories may be specified in the local_path argument and will trigger recursive uploads.
バージョン 1.0 で変更: Return value is now an iterable of uploaded remote file paths which also exhibits the .failed and .succeeded attributes.
バージョン 1.5 で変更: Allow a name attribute on file-like objects for log output
バージョン 1.7 で変更: Added use_glob option to allow disabling of globbing.
Reboot the remote system.
Will temporarily tweak Fabric’s reconnection settings (timeout and connection_attempts) to ensure that reconnection does not give up for at least wait seconds.
ノート
As of Fabric 1.4, the ability to reconnect partway through a session no longer requires use of internal APIs. While we are not officially deprecating this function, adding more features to it will not be a priority.
Users who want greater control are encouraged to check out this function’s (6 lines long, well commented) source code and write their own adaptation using different timeout/attempt values or additional logic.
バージョン 0.9.2 で追加.
バージョン 1.4 で変更: Changed the wait kwarg to be optional, and refactored to leverage the new reconnection functionality; it may not actually have to wait for wait seconds before reconnecting.
Check for given keys in the shared environment dict and abort if not found.
Positional arguments should be strings signifying what env vars should be checked for. If any of the given arguments do not exist, Fabric will abort execution and print the names of the missing keys.
The optional keyword argument used_for may be a string, which will be printed in the error output to inform users why this requirement is in place. used_for is printed as part of a string similar to:
"Th(is|ese) variable(s) (are|is) used for %s"
so format it appropriately.
The optional keyword argument provided_by may be a list of functions or function names or a single function or function name which the user should be able to execute in order to set the key or keys; it will be included in the error output if requirements are not met.
Note: it is assumed that the keyword arguments apply to all given keys as a group. If you feel the need to specify more than one used_for, for example, you should break your logic into multiple calls to require().
バージョン 1.1 で変更: Allow iterable provided_by values instead of just single values.
Run a shell command on a remote host.
If shell is True (the default), run will execute the given command string via a shell interpreter, the value of which may be controlled by setting env.shell (defaulting to something similar to /bin/bash -l -c "<command>".) Any double-quote (") or dollar-sign ($) characters in command will be automatically escaped when shell is True.
run will return the result of the remote program’s stdout as a single (likely multiline) string. This string will exhibit failed and succeeded boolean attributes specifying whether the command failed or succeeded, and will also include the return code as the return_code attribute. Furthermore, it includes a copy of the requested & actual command strings executed, as .command and .real_command, respectively.
Any text entered in your local terminal will be forwarded to the remote program as it runs, thus allowing you to interact with password or other prompts naturally. For more on how this works, see Interaction with remote programs.
You may pass pty=False to forego creation of a pseudo-terminal on the remote end in case the presence of one causes problems for the command in question. However, this will force Fabric itself to echo any and all input you type while the command is running, including sensitive passwords. (With pty=True, the remote pseudo-terminal will echo for you, and will intelligently handle password-style prompts.) See Pseudo-terminals for details.
Similarly, if you need to programmatically examine the stderr stream of the remote program (exhibited as the stderr attribute on this function’s return value), you may set combine_stderr=False. Doing so has a high chance of causing garbled output to appear on your terminal (though the resulting strings returned by run will be properly separated). For more info, please read Combining stdout and stderr.
To ignore non-zero return codes, specify warn_only=True. To both ignore non-zero return codes and force a command to run silently, specify quiet=True.
To override which local streams are used to display remote stdout and/or stderr, specify stdout or stderr. (By default, the regular sys.stdout and sys.stderr Python stream objects are used.)
For example, run("command", stderr=sys.stdout) would print the remote standard error to the local standard out, while preserving it as its own distinct attribute on the return value (as per above.) Alternately, you could even provide your own stream objects or loggers, e.g. myout = StringIO(); run("command", stdout=myout).
If you want an exception raised when the remote program takes too long to run, specify timeout=N where N is an integer number of seconds, after which to time out. This will cause run to raise a CommandTimeout exception.
If you want to disable Fabric’s automatic attempts at escaping quotes, dollar signs etc., specify shell_escape=False.
Examples:
run("ls /var/www/")
run("ls /home/myuser", shell=False)
output = run('ls /var/www/site1')
run("take_a_long_time", timeout=5)
バージョン 1.0 で追加: The succeeded and stderr return value attributes, the combine_stderr kwarg, and interactive behavior.
バージョン 1.0 で変更: The default value of pty is now True.
バージョン 1.0.2 で変更: The default value of combine_stderr is now None instead of True. However, the default behavior is unchanged, as the global setting is still True.
バージョン 1.5 で追加: The quiet, warn_only, stdout and stderr kwargs.
バージョン 1.5 で追加: The return value attributes .command and .real_command.
バージョン 1.6 で追加: The timeout argument.
バージョン 1.7 で追加: The shell_escape argument.
Run a shell command on a remote host, with superuser privileges.
sudo is identical in every way to run, except that it will always wrap the given command in a call to the sudo program to provide superuser privileges.
sudo accepts additional user and group arguments, which are passed to sudo and allow you to run as some user and/or group other than root. On most systems, the sudo program can take a string username/group or an integer userid/groupid (uid/gid); user and group may likewise be strings or integers.
You may set env.sudo_user at module level or via settings if you want multiple sudo calls to have the same user value. An explicit user argument will, of course, override this global setting.
Examples:
sudo("~/install_script.py")
sudo("mkdir /var/www/new_docroot", user="www-data")
sudo("ls /home/jdoe", user=1001)
result = sudo("ls /tmp/")
with settings(sudo_user='mysql'):
sudo("whoami") # prints 'mysql'
バージョン 1.0 で変更: See the changed and added notes for run.
バージョン 1.5 で変更: Now honors env.sudo_user.
バージョン 1.5 で追加: The quiet, warn_only, stdout and stderr kwargs.
バージョン 1.5 で追加: The return value attributes .command and .real_command.
バージョン 1.7 で追加: The shell_escape argument.


John Smith
- Address: 848 Abbott Road City: Stillfield, CT 08888 Phone: 999-999-999 Email<EMAIL_ADDRESS>Computer Programmer
Skills
-
- HTML
- CSS
- JavaScript
- Ruby, Rails, PHP, MySQL
- iOS, Swift, Mobile
Education
- College of San Mateo
Make School San Francisco
Hobbies
Painting with drones
Making music with insect sounds
Cooking with Ice Cubes