Restocat
========


TL;DR

Install Restocat CLI using following command:

``bash
npm install -g restocat-cli
`

Use Restocat CLI to create an empty project like this:

`bash
restocat init
`

Collections

Each collection is declared as a directory with the collection.json file by default. When Restocat initializes the application it recursively searches for such directories starting with your project root, and then via first-level dependencies in the ./node_modules directory.

The collection.json file consists of following:

* name – the name of the collection (optional). By default, this is the name of the directory. Please keep in mind that a parameter's name in a route definition must satisfy the regular expression /^[\w-]+$/i
* logic – a relative path to the file that exports a class or a constructor function for the collection's logic object (optional). By default, index.js will be used.
* endpointDefault – a relative path to the file that exports a class or a constructor function for the collection's logic object (optional). By default - true
* endpoints – map of the relationship between the route and handler (optional). By default:

`javascript
{
"get /": "list",
"post /": "create",
"get /:id": "one",
"put /:id": "update",
"delete /:id": "delete"
}
`

An example collection.json could look like this:

`javascript
{
"name": "Entities",
"description": "Some awesome and cool collection",
"logic": "./Entities.js",
"endpoints": {
"delete /:id": false, // don't use this endpoint
"put /:id": false,
"post /": false,
"get /sub-entities/": "subEntities", // custome endpoint
"get /sub-entities/:id": "subEntity"
}
}
`

Also, you can set your list of the endpoints by default:

`javascript

locator.registerInstance('defaultEndpoints', {
'get /': 'list',
'post /': 'create',
'get /:id': 'one'
})

`

Context

Restocat sets as the property $context for every instance of each collection.

$context has at least the following properties and methods:

* this.$context.request - the current request (IncomingMessage)
* this.$context.response - the current response (ResponseServer)

* this.$context.location – the current URI object that constains the current location.
* this.$context.referrer – the current URI object that contains the current referrer.

* this.$context.locator – the Service Locator of the application.
* this.$context.forward(collection_name:String, handle_name:String) – forwarding the current request to a other collection. This method is useful for creating a sub-collection flow
* this.$context.notFound() - correct 404 response from the server
* this.$context.redirect(uri:String, statusCode:Number) - correct http redirect
* this.$context.notSend() - a message to restocat what to call the send method is not necessary, we'll do it. Attention! It can not be caused by formatters and errorHandler

* this.$context.name - name of current collection
* this.$context.properties - properties from collection.json for current collection
* this.$context.handleName - handler name for current endpoint
* this.$context.state - the keys found in the path

Events

There are two ways of listening to a Restocat event:

* Subscribe on it using the Restocat application instance directly like this:

`javascript
const Restocat = require('restocat');
const restocat = new Restocat();

restocat.events.on('error', error => {
// some action
});
`

* Subscribe on it using the this.$context object of a collection using the same on or once methods.

`javascript
this.$context.on('error', error => {
// some action
});
`

Event names and arguments

| Event | When happens | Arguments |
|---------------|-------------------------------|-----------------------------------------------------------|
| trace | Trace message was sent | String |
| debug | Debug message was sent | String |
| info | Information message was sent | String |
| warn | Warning message was sent | String |
| error | Error message was sent | String \ Error |
| fatal | Fatal error message was sent | String \ Error |
| collectionLoaded | each collection is loaded | {name: String, properties: Object, constructor: function} |
| allCollectionsLoaded | all collections are loaded | Loaded collections by their names |
| incomingMessage | Request message | IncomingMessage |
| responseServer | Response server | ResponseServer, IncomingMessage |

Content Negotiation

If you're not using $context.notSend() Restocat will automatically select the content-type to respond with,
by finding the first registered formatter defined.
Also, note that if a content-type can't be negotiated, the default is application/octet-stream. Of course, you can always explicitly set the content-type:

`javascript

$context.response.setHeader('content-type', 'application/vnd.application+json');
$context.response.send({hello: 'world'});

`

Note that there are typically at least three content-types supported by Restocat (json, text and binary).
When you override or append to this, the "priority" might change; to ensure that the priority is set to what you want,
you should set a q-value on your formatter definitions, which will ensure sorting happens the way you want

So, if you are using the $context.notSend() and send the data manually, you should independently obtain and to use a formatter:

`javascript

const formatterProvider = this._serviceLocator.resolve('formatterProvider');
const formatter = formatterProvider.getFormatter(this.$context);

Promise.resolve(() => formatter(this.$context, myContent))
.then(content => this.$context.resposne.send(content));

`

Formatters

You can add additional formatters to Restocat:

`javascript

const Restocat = require('restocat');
const cat = new Restocat();
const server = cat.createServer();

server.register('formatter', {

// context - current context with request and response; data - data for response
'text/plain; q=0.3': (context, data) => {
const string = String(data);

context.response.setHeader('Content-Length', Buffer.byteLength(string));
context.response.setHeader('X-FORMATTER', 'CUSTOM');

return string;
}
});

`

Not implemented handler (Not found)

You can add your handler of the situation when the specified url was never found handler:

`javascript

const Restocat = require('restocat');
const cat = new Restocat();
const server = cat.createServer();

server.register('notImplementedHandler', $context => {
const NotFound = $context.locator.resolve('httpErrors').NotFoundError;

return Promise.reject(new NotFound('Not found handler for current url'));
});

`

Request API (IncomingMessage)

* cache(type:String, options:Object) - sets the cache-control header. type defaults to _public_, and options currently only takes maxAge.
* noCache() - turns off all cache related headers.
* getTime() - returns ms since epoch when request was setup
* charSet(type:String) - Appends the provided character set to the response's Content-Type
* getCharSet() - get char set
* getHeaders() - retrieves all headers off the response
* setHeader(name:String, value:String) - sets headers on the response
* json(code:Number, content:Object, headers:Object) - short hand method for: res.contentType = 'json'; res.send({hello: 'world'});`
* setLinkHeader(linkKey:String, rel:String) - sets the link header
* send(code:Number, content:Object|Error|Buffer) - sends the response object. convenience method that handles: writeHead(), write(), end()
* setStatus(code:Number) - sets the http status code on the response

Plugins and useful links
============
* Restocat Passport
* Restocat Logger
* Restocat Watcher

* Example