mithril/test-utils/xhrMock.js

A framework for building brilliant applications

"use strict"

var callAsync = require("../test-utils/callAsync")
var parseURL = require("../test-utils/parseURL")
var parseQueryString = require("../querystring/parse")

module.exports = function() {
	var routes = {}
	// var callback = "callback"
	var serverErrorHandler = function(url) {
		return {status: 500, responseText: "server error, most likely the URL was not defined " + url}
	}

	function FormData() {}
	var $window = {
		FormData: FormData,
		XMLHttpRequest: function XMLHttpRequest() {
			var args = {}
			var headers = {}
			var aborted = false
			this.setRequestHeader = function(header, value) {
				/*
				 the behavior of setHeader is not your expected setX API.
				 If the header is already set, it'll merge with whatever you add
				 rather than overwrite
				 Source: https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/setRequestHeader
				 */
				if (headers[header]) {
					headers[header] += ", " + value;
				} else {
					headers[header] = value
				}
			}
			this.getRequestHeader = function(header) {
				return headers[header]
			}
			this.open = function(method, url, async, user, password) {
				var urlData = parseURL(url, {protocol: "http:", hostname: "localhost", port: "", pathname: "/"})
				args.rawUrl = url
				args.method = method
				args.pathname = urlData.pathname
				args.search = urlData.search
				args.async = async != null ? async : true
				args.user = user
				args.password = password
			}
			this.responseType = ""
			this.response = null
			Object.defineProperty(this, "responseText", {get: function() {
				if (this.responseType === "" || this.responseType === "text") {
					return this.response
				} else {
					throw new Error("Failed to read the 'responseText' property from 'XMLHttpRequest': The value is only accessible if the object's 'responseType' is '' or 'text' (was '" + this.responseType + "').")
				}
			}})
			this.send = function(body) {
				var self = this
				if(!aborted) {
					var handler = routes[args.method + " " + args.pathname] || serverErrorHandler.bind(null, args.pathname)
					var data = handler({rawUrl: args.rawUrl, url: args.pathname, query: args.search || {}, body: body || null})
					self.status = data.status
					// Match spec
					if (self.responseType === "json") {
						try { self.response = JSON.parse(data.responseText) }
						catch (e) { /* ignore */ }
					} else {
						self.response = data.responseText
					}
				} else {
					self.status = 0
				}
				self.readyState = 4
				if (args.async === true) {
					callAsync(function() {
						if (typeof self.onreadystatechange === "function") self.onreadystatechange({target: self})
					})
				}
			}
			this.abort = function() {
				aborted = true
			}
		},
		document: {
			createElement: function(tag) {
				return {nodeName: tag.toUpperCase(), parentNode: null}
			},
			documentElement: {
				appendChild: function(element) {
					element.parentNode = this
					if (element.nodeName === "SCRIPT") {
						var urlData = parseURL(element.src, {protocol: "http:", hostname: "localhost", port: "", pathname: "/"})
						var handler = routes["GET " + urlData.pathname] || serverErrorHandler.bind(null, element.src)
						var data = handler({url: urlData.pathname, query: urlData.search, body: null})
						parseQueryString(urlData.search)
						callAsync(function() {
							if (data.status === 200) {
								new Function("$window", "with ($window) return " + data.responseText).call($window, $window)
							}
							else if (typeof element.onerror === "function") {
								element.onerror({type: "error"})
							}
						})
					}
				},
				removeChild: function(element) {
					element.parentNode = null
				},
			},
		},
		$defineRoutes: function(rules) {
			routes = rules
		},
		$defineJSONPCallbackKey: function(/* key */) {
			// callback = key
		},
	}
	return $window
}