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fluxible-plugin-fetchr

Fetchr Plugin for Fluxible

npm version

Provides isomorphic RESTful service access to your Fluxible application using fetchr.

Usage

var Fluxible = require('fluxible');
var fetchrPlugin = require('fluxible-plugin-fetchr');
var app = new Fluxible();
 
app.plug(fetchrPlugin({
    xhrPath: '/api' // Path for XHR to be served from 
}));

Now, when calling the createContext method on the server, make sure to send in the request object and optionally pass an xhrContext which will be used as parameters for all XHR calls:

app.createContext({
    req: req,
    xhrContext: { // Used as query params for all XHR calls
        lang: 'en-US', // make sure XHR calls receive the same lang as the initial request
        _csrf: 'a3fc2d' // CSRF token to validate on the server using your favorite library
    }
});

Registering Your Services

Registering fetchr services is done on the server side. Since the fetchr plugin is in control of the fetchr class, we expose this through the registerService method.

pluginInstance.registerService(yourService);

Or if you need to do this from your application without direct access to the plugin

app.getPlugin('FetchrPlugin').registerService(yourService);

For real examples, you can check out the server.js file in our chat example.

Exposing Your Services

Fetchr also contains an express/connect middleware that can be used as your access point from the client. Fetchr middleware expects that you're using the body-parser middleware (or an alternative middleware that populates req.body) before you use Fetchr middleware.

var server = express();
// you need to use body parser middleware before `FetchrPlugin` 
server.use(bodyParser.json());
server.use(pluginInstance.getXhrPath(), pluginInstance.getMiddleware());

For real examples, you can check out the server.js file in our chat example.

Dynamic XHR Paths

The fetchrPlugin method can also be passed a getXhrPath function that returns the string for the xhrPath. This allows you to dynamically set the xhrPath based on the current context. For instance, if you're hosting multiple sites and want to serve XHR via a pattern route like /:site/api, you can do the following:

app.plug(fetchrPlugin({
    getXhrPath: function (contextOptions) {
        // `contextOptions` is the object passed to `createContext` above 
        return contextOptions.req.params.site + '/api';
    }
}));

CORS Support

Fetchr provides CORS support by allowing you to pass the full origin host into corsPath.

For example:

var Fluxible = require('fluxible');
var fetchrPlugin = require('fluxible-plugin-fetchr');
var app = new Fluxible();
 
app.plug(fetchrPlugin({
    corsPath: 'http://www.foo.com',
    xhrPath: '/fooProxy'
}));

See Fetchr docs for more info

Context Variables

By Default, fetchr appends all context values to the xhr url as query params. contextPicker allows you to greater control over which context variables get sent as query params depending on the xhr method (GET or POST) See Fetchr docs for more info

Stats Monitoring & Analysis

To collect fetcher service's success/failure/latency stats, you can configure statsCollector for FetchrPlugin. The statsCollector function will be invoked with two arguments: actionContext and stats:

Example for how to configure statsCollector:

var Fluxible = require('fluxible');
var fetchrPlugin = require('fluxible-plugin-fetchr');
var app = new Fluxible();
 
app.plug(fetchrPlugin({
    corsPath: 'http://www.foo.com',
    xhrPath: '/fooProxy',
    statsCollector: function (actionContext, stats) {
        // just console logging as a naive example.  there is a lot more you can do here, 
        // like aggregating stats or filtering out stats you don't want to monitor 
        console.log('Request for resource', stats.resource,
            'with', stats.operation,
            'returned statusCode:', stats.statusCode,
            ' within', stats.time, 'ms');
    }
}));

API

License

This software is free to use under the Yahoo! Inc. BSD license. See the LICENSE file for license text and copyright information.