fake_xml_http_request.js

/**
 * @depend ../../sinon.js
 * @depend event.js
 */
/*jslint eqeqeq: false, onevar: false*/
/*global sinon, module, require, ActiveXObject, XMLHttpRequest, DOMParser*/
/**
 * Fake XMLHttpRequest object
 *
 * @author Christian Johansen (christian@cjohansen.no)
 * @license BSD
 *
 * Copyright (c) 2010-2013 Christian Johansen
 */
"use strict";

// wrapper for global
(function(global) {

    if (typeof sinon === "undefined") {
        global.sinon = {};
    }
    sinon.xhr = { XMLHttpRequest: global.XMLHttpRequest };

    var xhr = sinon.xhr;
    xhr.GlobalXMLHttpRequest = global.XMLHttpRequest;
    xhr.GlobalActiveXObject = global.ActiveXObject;
    xhr.supportsActiveX = typeof xhr.GlobalActiveXObject != "undefined";
    xhr.supportsXHR = typeof xhr.GlobalXMLHttpRequest != "undefined";
    xhr.workingXHR = xhr.supportsXHR ? xhr.GlobalXMLHttpRequest : xhr.supportsActiveX
                                     ? function() { return new xhr.GlobalActiveXObject("MSXML2.XMLHTTP.3.0") } : false;

    /*jsl:ignore*/
    var unsafeHeaders = {
        "Accept-Charset": true,
        "Accept-Encoding": true,
        "Connection": true,
        "Content-Length": true,
        "Cookie": true,
        "Cookie2": true,
        "Content-Transfer-Encoding": true,
        "Date": true,
        "Expect": true,
        "Host": true,
        "Keep-Alive": true,
        "Referer": true,
        "TE": true,
        "Trailer": true,
        "Transfer-Encoding": true,
        "Upgrade": true,
        "User-Agent": true,
        "Via": true
    };
    /*jsl:end*/

    function FakeXMLHttpRequest() {
        this.readyState = FakeXMLHttpRequest.UNSENT;
        this.requestHeaders = {};
        this.requestBody = null;
        this.status = 0;
        this.statusText = "";
        this.withCredentials = false;
        this.upload = new UploadProgress();

        var xhr = this;
        var events = ["loadstart", "load", "abort", "loadend"];

        function addEventListener(eventName) {
            xhr.addEventListener(eventName, function (event) {
                var listener = xhr["on" + eventName];

                if (listener && typeof listener == "function") {
                    listener(event);
                }
            });
        }

        for (var i = events.length - 1; i >= 0; i--) {
            addEventListener(events[i]);
        }

        if (typeof FakeXMLHttpRequest.onCreate == "function") {
            FakeXMLHttpRequest.onCreate(this);
        }
    }

    // An upload object is created for each
    // FakeXMLHttpRequest and allows upload
    // events to be simulated using uploadProgress
    // and uploadError.
    function UploadProgress() {
        this.eventListeners = {
            "progress": [],
            "load": [],
            "abort": [],
            "error": []
        }
    };

    UploadProgress.prototype.addEventListener = function(listenerName, callback) {
        this.eventListeners[listenerName].push(callback);
    };

    UploadProgress.prototype.dispatchEvent = function(event) {
        var listeners = this.eventListeners[event.type] || [];

        for (var i = 0, listener; (listener = listeners[i]) != null; i++) {
            listener(event);
        }
    };

    function verifyState(xhr) {
        if (xhr.readyState !== FakeXMLHttpRequest.OPENED) {
            throw new Error("INVALID_STATE_ERR");
        }

        if (xhr.sendFlag) {
            throw new Error("INVALID_STATE_ERR");
        }
    }

    // filtering to enable a white-list version of Sinon FakeXhr,
    // where whitelisted requests are passed through to real XHR
    function each(collection, callback) {
        if (!collection) return;
        for (var i = 0, l = collection.length; i < l; i += 1) {
            callback(collection[i]);
        }
    }
    function some(collection, callback) {
        for (var index = 0; index < collection.length; index++) {
            if(callback(collection[index]) === true) return true;
        };
        return false;
    }
    // largest arity in XHR is 5 - XHR#open
    var apply = function(obj,method,args) {
        switch(args.length) {
        case 0: return obj[method]();
        case 1: return obj[method](args[0]);
        case 2: return obj[method](args[0],args[1]);
        case 3: return obj[method](args[0],args[1],args[2]);
        case 4: return obj[method](args[0],args[1],args[2],args[3]);
        case 5: return obj[method](args[0],args[1],args[2],args[3],args[4]);
        };
    };

    FakeXMLHttpRequest.filters = [];
    FakeXMLHttpRequest.addFilter = function(fn) {
        this.filters.push(fn)
    };
    var IE6Re = /MSIE 6/;
    FakeXMLHttpRequest.defake = function(fakeXhr,xhrArgs) {
        var xhr = new sinon.xhr.workingXHR();
        each(["open","setRequestHeader","send","abort","getResponseHeader",
              "getAllResponseHeaders","addEventListener","overrideMimeType","removeEventListener"],
             function(method) {
                 fakeXhr[method] = function() {
                   return apply(xhr,method,arguments);
                 };
             });

        var copyAttrs = function(args) {
            each(args, function(attr) {
              try {
                fakeXhr[attr] = xhr[attr]
              } catch(e) {
                if(!IE6Re.test(navigator.userAgent)) throw e;
              }
            });
        };

        var stateChange = function() {
            fakeXhr.readyState = xhr.readyState;
            if(xhr.readyState >= FakeXMLHttpRequest.HEADERS_RECEIVED) {
                copyAttrs(["status","statusText"]);
            }
            if(xhr.readyState >= FakeXMLHttpRequest.LOADING) {
                copyAttrs(["responseText"]);
            }
            if(xhr.readyState === FakeXMLHttpRequest.DONE) {
                copyAttrs(["responseXML"]);
            }
            if(fakeXhr.onreadystatechange) fakeXhr.onreadystatechange.call(fakeXhr);
        };
        if(xhr.addEventListener) {
          for(var event in fakeXhr.eventListeners) {
              if(fakeXhr.eventListeners.hasOwnProperty(event)) {
                  each(fakeXhr.eventListeners[event],function(handler) {
                      xhr.addEventListener(event, handler);
                  });
              }
          }
          xhr.addEventListener("readystatechange",stateChange);
        } else {
          xhr.onreadystatechange = stateChange;
        }
        apply(xhr,"open",xhrArgs);
    };
    FakeXMLHttpRequest.useFilters = false;

    function verifyRequestSent(xhr) {
        if (xhr.readyState == FakeXMLHttpRequest.DONE) {
            throw new Error("Request done");
        }
    }

    function verifyHeadersReceived(xhr) {
        if (xhr.async && xhr.readyState != FakeXMLHttpRequest.HEADERS_RECEIVED) {
            throw new Error("No headers received");
        }
    }

    function verifyResponseBodyType(body) {
        if (typeof body != "string") {
            var error = new Error("Attempted to respond to fake XMLHttpRequest with " +
                                 body + ", which is not a string.");
            error.name = "InvalidBodyException";
            throw error;
        }
    }

    sinon.extend(FakeXMLHttpRequest.prototype, sinon.EventTarget, {
        async: true,

        open: function open(method, url, async, username, password) {
            this.method = method;
            this.url = url;
            this.async = typeof async == "boolean" ? async : true;
            this.username = username;
            this.password = password;
            this.responseText = null;
            this.responseXML = null;
            this.requestHeaders = {};
            this.sendFlag = false;
            if(sinon.FakeXMLHttpRequest.useFilters === true) {
                var xhrArgs = arguments;
                var defake = some(FakeXMLHttpRequest.filters,function(filter) {
                    return filter.apply(this,xhrArgs)
                });
                if (defake) {
                  return sinon.FakeXMLHttpRequest.defake(this,arguments);
                }
            }
            this.readyStateChange(FakeXMLHttpRequest.OPENED);
        },

        readyStateChange: function readyStateChange(state) {
            this.readyState = state;

            if (typeof this.onreadystatechange == "function") {
                try {
                    this.onreadystatechange();
                } catch (e) {
                    sinon.logError("Fake XHR onreadystatechange handler", e);
                }
            }

            this.dispatchEvent(new sinon.Event("readystatechange"));

            switch (this.readyState) {
                case FakeXMLHttpRequest.DONE:
                    this.dispatchEvent(new sinon.Event("load", false, false, this));
                    this.dispatchEvent(new sinon.Event("loadend", false, false, this));
                    this.upload.dispatchEvent(new sinon.Event("load", false, false, this));
                    try {
                        window.ProgressEvent && this.upload.dispatchEvent(new ProgressEvent("progress", {loaded: 100, total: 100}));
                    }
                    catch (ex) {
                        this.upload.dispatchEvent(document.createEvent("ProgressEvent"));
                    }
                    break;
            }
        },

        setRequestHeader: function setRequestHeader(header, value) {
            verifyState(this);

            if (unsafeHeaders[header] || /^(Sec-|Proxy-)/.test(header)) {
                throw new Error("Refused to set unsafe header \"" + header + "\"");
            }

            if (this.requestHeaders[header]) {
                this.requestHeaders[header] += "," + value;
            } else {
                this.requestHeaders[header] = value;
            }
        },

        // Helps testing
        setResponseHeaders: function setResponseHeaders(headers) {
            this.responseHeaders = {};

            for (var header in headers) {
                if (headers.hasOwnProperty(header)) {
                    this.responseHeaders[header] = headers[header];
                }
            }

            if (this.async) {
                this.readyStateChange(FakeXMLHttpRequest.HEADERS_RECEIVED);
            } else {
                this.readyState = FakeXMLHttpRequest.HEADERS_RECEIVED;
            }
        },

        // Currently treats ALL data as a DOMString (i.e. no Document)
        send: function send(data) {
            verifyState(this);

            if (!/^(get|head)$/i.test(this.method)) {
                if (this.requestHeaders["Content-Type"]) {
                    var value = this.requestHeaders["Content-Type"].split(";");
                    this.requestHeaders["Content-Type"] = value[0] + ";charset=utf-8";
                } else {
                    this.requestHeaders["Content-Type"] = "text/plain;charset=utf-8";
                }

                this.requestBody = data;
            }

            this.errorFlag = false;
            this.sendFlag = this.async;
            this.readyStateChange(FakeXMLHttpRequest.OPENED);

            if (typeof this.onSend == "function") {
                this.onSend(this);
            }

            this.dispatchEvent(new sinon.Event("loadstart", false, false, this));
        },

        abort: function abort() {
            this.aborted = true;
            this.responseText = null;
            this.errorFlag = true;
            this.requestHeaders = {};

            if (this.readyState > sinon.FakeXMLHttpRequest.UNSENT && this.sendFlag) {
                this.readyStateChange(sinon.FakeXMLHttpRequest.DONE);
                this.sendFlag = false;
            }

            this.readyState = sinon.FakeXMLHttpRequest.UNSENT;

            this.dispatchEvent(new sinon.Event("abort", false, false, this));

            this.upload.dispatchEvent(new sinon.Event("abort", false, false, this));

            if (typeof this.onerror === "function") {
                this.onerror();
            }
        },

        getResponseHeader: function getResponseHeader(header) {
            if (this.readyState < FakeXMLHttpRequest.HEADERS_RECEIVED) {
                return null;
            }

            if (/^Set-Cookie2?$/i.test(header)) {
                return null;
            }

            header = header.toLowerCase();

            for (var h in this.responseHeaders) {
                if (h.toLowerCase() == header) {
                    return this.responseHeaders[h];
                }
            }

            return null;
        },

        getAllResponseHeaders: function getAllResponseHeaders() {
            if (this.readyState < FakeXMLHttpRequest.HEADERS_RECEIVED) {
                return "";
            }

            var headers = "";

            for (var header in this.responseHeaders) {
                if (this.responseHeaders.hasOwnProperty(header) &&
                    !/^Set-Cookie2?$/i.test(header)) {
                    headers += header + ": " + this.responseHeaders[header] + "\r\n";
                }
            }

            return headers;
        },

        setResponseBody: function setResponseBody(body) {
            verifyRequestSent(this);
            verifyHeadersReceived(this);
            verifyResponseBodyType(body);

            var chunkSize = this.chunkSize || 10;
            var index = 0;
            this.responseText = "";

            do {
                if (this.async) {
                    this.readyStateChange(FakeXMLHttpRequest.LOADING);
                }

                this.responseText += body.substring(index, index + chunkSize);
                index += chunkSize;
            } while (index < body.length);

            var type = this.getResponseHeader("Content-Type");

            if (this.responseText &&
                (!type || /(text\/xml)|(application\/xml)|(\+xml)/.test(type))) {
                try {
                    this.responseXML = FakeXMLHttpRequest.parseXML(this.responseText);
                } catch (e) {
                    // Unable to parse XML - no biggie
                }
            }

            if (this.async) {
                this.readyStateChange(FakeXMLHttpRequest.DONE);
            } else {
                this.readyState = FakeXMLHttpRequest.DONE;
            }
        },

        respond: function respond(status, headers, body) {
            this.setResponseHeaders(headers || {});
            this.status = typeof status == "number" ? status : 200;
            this.statusText = FakeXMLHttpRequest.statusCodes[this.status];
            this.setResponseBody(body || "");
        },

        uploadProgress: function uploadProgress(progressEventRaw) {
            this.upload.dispatchEvent(new ProgressEvent("progress", progressEventRaw));
        },

        uploadError: function uploadError(error) {
            this.upload.dispatchEvent(new CustomEvent("error", {"detail": error}));
        }
    });

    sinon.extend(FakeXMLHttpRequest, {
        UNSENT: 0,
        OPENED: 1,
        HEADERS_RECEIVED: 2,
        LOADING: 3,
        DONE: 4
    });

    // Borrowed from JSpec
    FakeXMLHttpRequest.parseXML = function parseXML(text) {
        var xmlDoc;

        if (typeof DOMParser != "undefined") {
            var parser = new DOMParser();
            xmlDoc = parser.parseFromString(text, "text/xml");
        } else {
            xmlDoc = new ActiveXObject("Microsoft.XMLDOM");
            xmlDoc.async = "false";
            xmlDoc.loadXML(text);
        }

        return xmlDoc;
    };

    FakeXMLHttpRequest.statusCodes = {
        100: "Continue",
        101: "Switching Protocols",
        200: "OK",
        201: "Created",
        202: "Accepted",
        203: "Non-Authoritative Information",
        204: "No Content",
        205: "Reset Content",
        206: "Partial Content",
        300: "Multiple Choice",
        301: "Moved Permanently",
        302: "Found",
        303: "See Other",
        304: "Not Modified",
        305: "Use Proxy",
        307: "Temporary Redirect",
        400: "Bad Request",
        401: "Unauthorized",
        402: "Payment Required",
        403: "Forbidden",
        404: "Not Found",
        405: "Method Not Allowed",
        406: "Not Acceptable",
        407: "Proxy Authentication Required",
        408: "Request Timeout",
        409: "Conflict",
        410: "Gone",
        411: "Length Required",
        412: "Precondition Failed",
        413: "Request Entity Too Large",
        414: "Request-URI Too Long",
        415: "Unsupported Media Type",
        416: "Requested Range Not Satisfiable",
        417: "Expectation Failed",
        422: "Unprocessable Entity",
        500: "Internal Server Error",
        501: "Not Implemented",
        502: "Bad Gateway",
        503: "Service Unavailable",
        504: "Gateway Timeout",
        505: "HTTP Version Not Supported"
    };

    sinon.useFakeXMLHttpRequest = function () {
        sinon.FakeXMLHttpRequest.restore = function restore(keepOnCreate) {
            if (xhr.supportsXHR) {
                global.XMLHttpRequest = xhr.GlobalXMLHttpRequest;
            }

            if (xhr.supportsActiveX) {
                global.ActiveXObject = xhr.GlobalActiveXObject;
            }

            delete sinon.FakeXMLHttpRequest.restore;

            if (keepOnCreate !== true) {
                delete sinon.FakeXMLHttpRequest.onCreate;
            }
        };
        if (xhr.supportsXHR) {
            global.XMLHttpRequest = sinon.FakeXMLHttpRequest;
        }

        if (xhr.supportsActiveX) {
            global.ActiveXObject = function ActiveXObject(objId) {
                if (objId == "Microsoft.XMLHTTP" || /^Msxml2\.XMLHTTP/i.test(objId)) {

                    return new sinon.FakeXMLHttpRequest();
                }

                return new xhr.GlobalActiveXObject(objId);
            };
        }

        return sinon.FakeXMLHttpRequest;
    };

    sinon.FakeXMLHttpRequest = FakeXMLHttpRequest;

})(typeof global === "object" ? global : this);

if (typeof module !== 'undefined' && module.exports) {
    module.exports = sinon;
}