REST in Place

                              _______
                             /       \, R.I.P., -------------

REST in Place is an AJAX Inplace-Editor that talks to RESTful controllers.
It requires absolutely no additional server-side code if your controller
fulfills the following REST preconditions:

• It uses the HTTP PUT method to update a record
• It delivers an object in JSON form for requests with
  "Accept: application/json" headers

The editor works by PUTting the updated value to the server and GETting the
updated record afterwards to display the updated value.
That way any authentication methods or otherwise funky workflows in your
controllers are used for the inplace-editors requests.

To save the additional GET request, you can take the shortcut of returning the
updated record in the response to the PUT request. See the testapp for an
example.

URL: http://github.com/janv/rest_in_place/
REPOSITORY: git://github.com/janv/rest_in_place.git
BLOG: http://jan.varwig.org/projects/rest-in-place

If you like REST in Place, you can flattr me:

Requirements

Rails

Since I guess most people use REST in Place in Rails apps, I turned this
entire thing into a gem that you can require in your Gemfile. It requires
jQuery, but it will NOT install a jquery-rails dependency. This is done so
you aren't forced to use jquery-rails if you want to run a more up-to-date
version of jQuery. Just make sure that jQuery is there.

REST in Place requires Rails >= 3.1 as a dependency since it loads through the
asset pipeline.

CoffeeScript

The CoffeeScript code (lib/assets/javascripts/rest_in_place/rest_in_place.coffee.erb)
only relies on the presence of jQuery. You can extract just that file and use
it with whatever framework in whatever server-side language you want, given
that you follow the coventions described later in this document.

Even though this is processed by ERB to sniff out some relevant Rails settings,
you can use it as a CoffeeScript file without modification. (This feature
might vanish at any time in the future, tying RIP closer to Rails).

JavaScript only

If you're still using JavaScript, give CoffeeScript
a try. It's a preprocessor/different syntax, that makes writing JavaScript
bearable. If you absolutely don't want to learn anything new, just convert
REST in Place to JavaScript using http://js2coffee.org/ before including it in
your project.

Installation

Just add

gem 'rest_in_place'

to your Gemfile.

Then load the JavaScript by adding <%= javascript_include_tag "rest_in_place" %>
into your layout. Alternatively you can require 'rest_in_place' in your
JavaScript files in app/assets, for example in your application.js:

//= require 'rest_in_place'

In both cases, make sure you load REST in Place after jQuery.

Rails Request Forgery Protection

For REST in Place to work with Rails request forgery protection, you need to
have the Rails CSRF meta tags in your HTML head:

<%= csrf_meta_tags %>

Usage Instructions

To make a piece of Text inplace-editable, wrap it into an element (a span
usually) with class "rest-in-place". The editor needs 3 pieces of information
to work: a URL, an object name and the attribute name. These are provided as
follows:

• put attributes into the element, like this:

  <span class="rest-in-place" data-url="/users/1" data-object="user" data-attribute="name" data-placeholder="Enter a name">
    <%= @user.name %>
  </span>
  

• if any of these attributes is missing, DOM parents of the element are searched
  for them. That means you can write something like:

  <div data-object="user" data-url="/users/1">
    Name:  <span class="rest-in-place" data-attribute="name" ><%= @user.name %></span><br/>
    eMail: <span class="rest-in-place" data-attribute="email"><%= @user.email %></span>
  </div>
  

• You can completely omit the URL to use the current document's URL.
  With proper RESTful controllers this should always work, the explicit
  URL-attribute is for cases when you want to edit a resource that is
  displayed as part of a non-RESTful webpage.

• Rails provides the DOM helper that constructs a DOM id out of an
  ActiveRecord for you. So, your HTML page may look like this:

  <div id="<%= dom_id @user # == "user_1" %>">
    Name:  <span class="rest-in-place" data-attribute="name" ><%= @user.name %></span><br/>
    eMail: <span class="rest-in-place" data-attribute="email"><%= @user.email %></span>
  </div>
  

  REST in Place recognizes dom_ids of this form and derives the object parameter
  from them, so that (with the current documents URL used) you really only need
  to provide the attributes name in most cases.

  Note that a manually defined (in the element or in one of the parents)
  object always overrides dom_id recognition.

• REST in Place supports multiple form types. The default type is a input
  field, a textarea is also supported. To select a form type use the
  data-formtype attribute in the element and set it to the name of your
  formtype ( input, or textarea ).

  To write your own form types, just extend the RestInPlace.forms object
  and select your new form type throught the data-formtype attribute.

Elements with the class rest-in-place are picked up automatically upon
document.ready. For other elements, grab them via jQuery and call
.restInPlace() on the jQuery object.

$('.my-custom-class').restInPlace()

Events

A REST in Place instance triggers four different events on the element that
it's associated with:

• activate.rest-in-place when starting the editing of the element.
  Triggering the event is the first thing that happens, before any processing
  and form building takes place. That means you can use this event to modify
  the content of the element (for example to remove number/date formatting).

• ready.rest-in-place when the form has been built. This event can be used
  e.g. to change the size of the field or textarea.

• success.rest-in-place with the data retrieved from the server as an
  extra parameter after a successful save on the server.
  This event is triggered at the very latest moment, after the element has
  been restored with the data from the server. This means you can use the
  event handler to further modify the data and overwrite the displayed value
  (useful for number/date formatting for example).

• failure.rest-in-place after an error occurred. The second argument will be
  jQuery's responseJSON, so it is possible to handle (for instance) server-side
  validation errors.

  $('#my-editable-element').bind('failure.rest-in-place', function(event, json) {
      $el = $(this);
      attr = $el.data("attribute");
      error_message = json[attr].join(", ");
      $el.after("<span class='error'>#{error_message}</span>");
  });
  

• update.rest-in-place immediately before sending the update to the server

• abort.rest-in-place when the user aborts the editing process.

Bind to these events through the jQuery event mechanisms:

$('#my-editable-element').bind('success.rest-in-place', function(event, data){
  console.log("Yay it worked! The new value is", data.whatever);
});

Example

Your routes.rb:

resources :users

Your app/controllers/users_controller.rb:

class UsersController < ApplicationController
  def show
    @user = User.find params[:id]
    respond_to do, format, format.html
      format.json {render :json => @user}
    end
  end

  def update
    @user = User.find params[:id]
    if @user.update_attributes!(params[:user])
      respond_to do, format, format.html { redirect_to( @person )}
        format.json { render :json => @user }
      end
    else
      respond_to do, format, format.html { render :action  => :edit } # edit.html.erb
        format.json { render :nothing =>  true }
      end
    end
  end
end

Your app/views/users/show.html.erb:

<div id="<%= dom_id @user %>">
  ID: <%= @user.id %><br />
  Name: <span class="rest-in-place" data-formtype="input" data-attribute="name"><%= @user.name %></span><br/><br/>
  Hobbies: <span class="rest-in-place" data-formtype="textarea" data-attribute="hobbies"><%= @user.hobbies %></span>
</div>

You can run this example by running to the testapp included in this
plugin with script/server (SQLite3 required) and visiting
localhost:3000/users/

Hint:
you might need to set up the database first.
Copy and edit testapp/config/database.yml.sample accordingly.
If you don't want to use the included SQLite3 database, run rake db:create
and rake db:schema:load.

Troubleshooting

REST in Place is very picky about correct headers and formatting.
If you experience errors, please make sure your controller sends responses as
properly formatted JSON with the correct MIME-Type "application/json".

Testing

The repository contains a testapp directory with a rails app that can be
used to test REST in Place. Run bundle exec rake db:seed and head to http://localhost:3000 to see it in
action.

There's also an automated Jasmine spec suite running at
http://localhost:3000/jasmine. You can find the sources for the specs at
testapp/app/assets/javascripts/spec.coffee

Participation

I'd love to get comments, bug reports (or better, pull-requests) about REST in
Place. For this, you can either fork the project to send a pull request, or
submit a bug in the tracker at GitHub:
http://github.com/janv/rest_in_place/issues

For general comments and questions, please use the comment function on my blog:
http://jan.varwig.org/projects/rest-in-place

If you send pull requests be sure to also add tests and make sure the existing
tests pass.

Copyright (c) 2013 [Jan Varwig], released under the MIT license