mekanika-adapter-http

adapter-http

Query envelope to HTTP adapter

Install

npm install mekanika-adapter-http

CommonJS:

var http = require('mekanika-adapter-http');

Browser (exposes as HttpAdapter globals):

<script src="dist/adapter-http.min.js"></script>

Usage

The HTTP adapter exposes an .exec( qe, callback ) method and a .config object property.

http.exec( {do:'find', on:'users'}, function (err, res) {
  if (err) throw new Error(err);
  console.log( res );
});

.exec( qe, cb )

The adapter can be run calling exec and passing it:

• qe - a valid Mekanika Qe
• cb - a callback that accepts (err, res) parameters

The query envelope MUST sepcify an action: {do:'find'} which is used to run a superagent call (eg. post(), get() etc).

Exec returns the superagent instance, and passes its results to the callback:

err - Error handling

A superagent error object. Information on error handling is available via superagent error docs.

res - Response handling

Superagent response object.

Some notable res properties:

• res.text - unparsed response body string
• res.body - parsed according to Content-Type (may be empty)
• res.header - object of parsed header fields
• res.type - Content-Type void of the charset
• res.charset - content type charset if provided
• res.error - provided on 4xx and 5xx responses
• res.status - response status flags

Config

Config defaults as follows, each of which can be overridden before calling .exec():

exports.config = {
    protocol: 'http'
  , host: 'localhost'
  , port: 80
  , contentType: 'application/json'
  , withCredentials: false
  , headers: {}
}

Config affects how superagent creates the call and where it points to.

HTTP request and URL construction

The base URL constructed from adapter config is as follows:

protocol:// + host + :port [+ /resource]

The port is omitted from the URL if is the default 80. The resource is added if one is provided, and ids are appended to the resource URL (separated by commas if several are provided). URL queries are appended if provided by the Qe.

The HTTP request methods map to the default Qe actions as follows:

Qe action	HTTP method
find	GET
create	POST
update	POST
remove	DELETE

find and update requests append Qe identifiers to the URL. So a Qe of {on:'users', ids:['12345']}, would by default build the following URL:

http://localhost/users/12345

Multiple ids are separated by commas {on:'users', ids:['12345','14421']}

http://localhost/users/12345,14421

Tests

Ensure you have installed the development dependencies:

npm install

To run the tests:

npm test

Coverage

Coverage reports are generated with istanbul (npm install -g istanbul):

npm run coverage

License

Copyright 2013-2015 Mekanika

Released under the MIT License (MIT)