libdom-http/src/lib/driver/xhr2.js

Http support for libdom

'use strict';

import {
            number,
            middleware
        } from "libcore";
        
import {
            on,
            un
        } from "libdom";

import DETECT from "../detect.js";

import XHR from "./xhr.js";

var MIDDLEWARE = middleware("libdom-http.driver.xhr"),
    BEFORE_REQUEST = "before:request",
    PROTOTYPE = XHR.prototype,
    BINDS = PROTOTYPE.bindMethods,
    BIND_LENGTH = BINDS.length,
    PROGRESS = DETECT.xhrbytes,
    features = 0;

// timeout
function addTimeout(instance, request) {
    var timeout = request.settings('timeout');
    
    if (number(timeout) && timeout > 10) {
        request.xhrTransport.timeout = timeout;
    }
}

// withCredentials
function addWithCredentials(instance, request) {

    if (request.settings('withCredentials') === true) {
        request.xhrTransport.withCredentials = true;
    }
}

// Progress
function onProgress(event) {
    /* jshint validthis: true */
    var instance = this,
        request = instance.request,
        api = request.api;
    var loaded;
    
    if (request && event.lengthComputable) {
        loaded = event.loaded / event.total;
        
        request.percentLoaded = loaded;
        if (api) {
            api.percentLoaded = loaded;
        }
    }

}

function addProgressEvent(instance, request) {
    var api = request.api;
    
    api.percentLoaded = 0;
    
    if (request) {
        request.percentLoaded = 0;
    }
    
    on(request.xhrTransport, 'progress', instance.onProgress);
}

// cleanup
function cleanup(instance, request) {
    if (PROGRESS) {
        un(request.xhrTransport, 'progress', instance.onProgress);
    }
}


function processFormData(instance, request) {

    // remove content type and use FormData defaults
    if (request.body instanceof global.FormData) {
        delete request.headers['Content-type'];
    }

}



// apply middlewares according to capability of the platform
if (DETECT.xhrx) {
    features++;
    MIDDLEWARE.register(BEFORE_REQUEST, addWithCredentials);
}

// form data fixes
if (DETECT.formdata) {
    features++;
    MIDDLEWARE.register(BEFORE_REQUEST, processFormData);
}

// progress
if (PROGRESS) {
    features++;
    BINDS[BIND_LENGTH++] = 'onProgress';
    PROTOTYPE.onProgress = onProgress;
    MIDDLEWARE.register(BEFORE_REQUEST, addProgressEvent);
}

// timeout
if (DETECT.xhrtime) {
    MIDDLEWARE.register(BEFORE_REQUEST, addTimeout);
}



// cleanup
if (features) {
    if (features > 2) {
        PROTOTYPE.level = 2;
    }
    MIDDLEWARE.register("cleanup", cleanup);
}


export default XHR;