Documentation and Testing the sTeam-REST API

sTeam REST API

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sTeam server project repository: sTeam.
sTeam-REST API repository: sTeam-REST

REST Services

REST is the software architectural style of the World Wide Web. REST (Representational State Transfer) was introduced Roy Fielding in his doctoral dissertation in 2000. Its purpose is to induce performance, scalability, simplicity, modifiability, visibility, portability, and reliability.It has client/server relationship with a uniform interface and is stateless. REST is most commonly associated with HTTP but it is not strictly related to it.

REST Principles

  • Resources : Each and every component is a resource.A resource is accessed by a common interface using HTTP standard methods.
  • Messages use HTTP methods like GET, POST, PUT, and DELETE.
  • Resource identification through URI: Resources are identified using URI. Resources are represented using JSON or XML.
  • Stateless interactions take place between the server and the client. No context is saved for the requests at the server.The client maintains the state of the session.

HTTP methods

The CRUD(create, retrieve, update and delete ) operations are performed using the HTTP methods.

GET

It is used to retrieve information. GET requests executed any number of times with the same parameters, the results would not change. This makes it idempotent. Partial or conditional requests can be sent. It is a read only type of operation.

Retrieve a list of users:

GET /api.example.com/UserService/users

POST

POST is usually used to create a new entity. It can also be used to update an existing entity. The request will have to do something with the entity provided in the URI.

Create a new user with an ID 2:

POST /api.example.com/UserService/users/2tg

PUT

PUT request is always idempotent. Executing the same request any number of times will not change the output. PUT can be used to create or update an existing entity.

Modify the user with an ID of 1:

PUT /api.example.com/UserService/users/1

PATCH

It is idempotent. PATCH requests only updates the specified fields of an entity.

Modify a user with an id of 1:

PATCH /api.example.com/UserService/users/1

DELETE

It can be asynchronous or a long-running request. It removes the resource. It can be removed immediately or at a later instance of time.

Delete a user with an ID of 1:

DELETE /api.example.com/UserService/users/1

 sTeam-REST API

Installing and activating the REST API

The REST API is developed as an application inside the sTeam server. This simplifies development quite a lot, as we don’t need to restart the server for every change. Instead just the API code gets updated and reloaded. It may eventually be integrated into the core, however the longterm plan is actually to move functionality out of the core, to make development easier.

To get the current version of the API clone the steam-rest repo into your home or to any place where you keep your development repos. Then change to the tools directory of your installation and run import-from-git.

git clone https://github.com/societyserver/steam-rest
cd steam-rest
git checkout origin/rest.pike
export steamrest=`pwd`
cd /usr/local/lib/steam/tools
./import-from-git.pike -u root $steamrest /

Note: The new import-from-git.pike script supports importing documents of all mime types.

It is important that the first import is done as root because the API code needs to run with root privileges and it will only do that if the object that holds the source is created as root.

Once the api code is loaded there are just a few tweaks needed to make it work.

We need to fix the mime-type, as the import script is not doing that yet.

OBJ("/sources/rest.pike")->set_attribute("DOC_MIME_TYPE", "source/pike");

Changing the mime type will change the class of the rest api script from Document to DocLpc.

> OBJ("/sources/rest.pike");                                               
(1) Result: 127.0.0.1:1900/rest.pike(#840,/classes/Document,17,source/pike)
> OBJ("/sources/rest.pike");                                               
(2) Result: 127.0.0.1:1900/rest.pike+(#840,/classes/DocLpc,529,source/pike,0 Instances, ({  }))

This takes a moment, check the type a few times until it’s done. Then instantiate an object from the source, give it a proper name, and move it to the /scripts/ container”

object rest = OBJ("/sources/rest.pike")->provide_instance();
rest->set_attribute("OBJ_NAME", "rest.pike");
rest->move(OBJ("/scripts/"));

Instantiating the object needs to be done as sTeam-root, in order for it to have permissions to run on behalf of other users.

Once this is done you are ready to start using the API.

sTeam-REST API tests

The project contains a set of examples and tests for the RESTful API for the sTeam server.

The code is written in coffee script and needs node.js only for coffeescript translation. Deployment can be done as static javascript files, and does not need any kind of dynamic server for the front-end. The back-end is a RESTful API written for the sTeam server as used by steam.realss.com

Development instructions

step 1: install node.js

http://nodejs.org/download/

step 2: clone the repository

git clone https://github.com/societyserver/steam-rest

step 3: install node packages:

npm install

This installs all dependencies (including coffee) for our project into the project’s node_modules directory based on the ‘package.json’ file

step 4: start the server

node_modules/.bin/coffee scripts/server.coffee

but for convenience we can install coffee in the global node environment:

npm install -g coffee-script

so we can just say

coffee scripts/server.coffee

if the server is working you’ll see:

Listening on port 7000

Testing

FrisbyJS is used to test the API. It is run through Jasmine and is based on nodejs.

Once you have nodejs installed, run the following statement to install Frisby and Jasmine:

npm install -g jasmine-node frisby

Then execute the test by:

cd project/directory
jasmine-node test/

The karma testing framework is also used for testing the sTeam REST API.

There were some inherent issues with the test framework which were addressed.

Issue. Github Issue Github PR
Update Readme.md Update Readme PR-2
Add javascript dependencies Issue-4 PR-6
Add node dependencies Issue-5 PR-7
Add angular-mocks.js script for testing the REST services. Issue-8 PR-9

The project dependencies were not met and this resulted into the error when the project was run on the localhost. The angular-ui-router, angular-bootstrap and bootstrap js frameworks were not installed in the node modules of the project. As a result the bower.json script was modified to include these dependencies.

bower.json

{
  "name": "bower",
  "version": "0.1",
  "private": true,
  "ignore": [
    "**/.*",
    "node_modules",
    "bower_components",
    "test",
    "tests"
  ],
  "dependencies": {
    "angular": "",
    "angular-route": "~1.4.8",
    "angular-ui-router": "",
    "angular-bootstrap": "",
    "bootstrap": ""
  }
}

The node dependencies of karma, frisby and jasmine-node were included in the package.json. These would be installed when the npm install is executed.

package.json

{
"name": "TechGrind",
"version": "0.1.1",
"private": true,
"dependencies": {
"express": "",
"coffee-script": "",
"morgan": "",
"compression": "",
"method-override": "",
"body-parser": "",
"serve-static": "",
"errorhandler": "",
"bower": "",
"jasmine-node": "",
"frisby": "",
"karma": ""
},
"production_dirs": {
"coffee_src": "src/",
"src": "app/",
"dest": "app_production/"
},
"devDependencies": {
},
"scripts": {
"postinstall": "bower install"
}
}

Feel free to contribute to the repository. Suggestions are welcomed.

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