/*global exports, define, global, require, _, Backbone */
Backbone Faux Server v0.10.5
https://github.com/biril/backbone-faux-server
Licensed and freely distributed under the MIT License
Copyright (c) 2012-2014 Alex Lambiris
/*global exports, define, global, require, _, Backbone */
(function (root, createModule) {
"use strict";
Detect current environment. Faux-server will be exposed as module / global accordingly:
A global exports
object signifies CommonJS-like enviroment that supports module.exports
,
e.g. Node
if (typeof exports === "object") {
return createModule(exports, require("underscore"), require("backbone"));
}
A global define
method with an amd
property signifies the presence of an AMD loader
(require.js, curl.js)
if (typeof define === "function" && define.amd) {
return define(["underscore", "backbone", "exports"], function (_, Backbone, exports) {
return createModule(exports, _, Backbone);
});
}
Otherwise we assume running in a browser:
Save a reference to previous value of fauxServer
before (potentially) overwriting it - so
that it can be restored on noConflict
var previousFauxServer = root.fauxServer;
createModule(root.fauxServer = {}, _, Backbone);
The noConflict
method sets the fauxServer
global to to its previous value (once),
returning a reference to fauxServer
(always)
root.fauxServer.noConflict = function () {
var fauxServer = root.fauxServer;
root.fauxServer = previousFauxServer;
return (fauxServer.noConflict = function () { return fauxServer; }).call();
};
}(this, function (fauxServer, _, Backbone) {
"use strict";
var
A no-op method to reuse
noOp = function () {},
Clone an array skipping all tail-elements which are undefined. Array.length
can’t be
trusted for arrays containing tail-element(s) explicitly set to undefined
as it’s
always set to the index of the last element plus one - and a tail element explicitly
set to undefined will in fact count as the ‘last element’. Problematic when counting
function arguments in order to sanitize, provide defaults, etc
skipUndefinedTail = function (array) {
var a = [], i = array.length - 1;
for (; i >= 0; i--) { if (!_.isUndefined(array[i])) { a[i] = array[i]; } }
return a;
},
Convert a urlExp string - a string containing parameter parts (‘:param’), splat parts (‘*splat’) and parentheses into a regular expression
makeRegExp = (function () {
var
To escape special chars before converting to reg-exp
e = /[\-{}\[\]+?.,\\\^$|#\s]/g,
Optional part
o = /\((.*?)\)/g,
Named param (+ extra capturing parens for opt-part detection)
p = /(\(\?)?:[A-Za-z_](?:\w)+/g,
Splat param
s = /\*\w+/g,
Don’t confuse (regex-equivalent-subsituted) optional parts with named params
getReplacementForP = function (match, isOptPart) {
return isOptPart ? match : "([^\/]+)";
};
return function(exp) {
exp = exp.replace(e, "\\$&")
.replace(o, "(?:$1)?")
.replace(p, getReplacementForP)
.replace(s, "(.*?)");
return new RegExp("^" + exp + "$");
};
}()),
Save a reference to the native sync method. Will be invoked when no route is matched during sync (and there’s no default-route) or faux-server is disabled altogether
nativeSync = Backbone.sync,
Indicates whether faux-server is currently enabled
isEnabled = true,
The default-route - a route that contains the default handler if one is defined. The
default handler is invoked when no matching route is found for some model-URL /
sync-method pair and may be set by means of setDefaultHandler
. A null
value
signifies the absence of a default handler
defaultRoute = null,
Server’s emulated latency
latency = 0,
Mapping of CRUD (+ patch) to HTTP verbs
crudToHttp = {
"create": "POST",
"read": "GET",
"update": "PUT",
"delete": "DELETE",
"patch": "PATCH"
},
Collection of all defined routes
routes = [],
Get a route matching the given <url
, httpMethod
> pair. Routes that exactly match the
HTTP-method take precedence over match-all-methods routes (those with httpMethod
set
to ‘*’). Matching routes that were defined later take precedence over those that were
defined earlier. A returned matching route will contain the additional handlerParams
property: an array containing params that are to be passed to the handler as captured
when the given URL was matched. Will return null
if no route found. Note that
the acquired route is a copy - it cannot be modified to affect faux-server’s behaviour
getMatchingRoute = function (url, httpMethod) {
var i, r, weakMatch;
for (i = routes.length - 1; i >= 0; --i) { // Iterating from latest to earliest
r = routes[i];
if (r.urlExp.test(url)) {
if (r.httpMethod === httpMethod) { // Found a match ..
r = _.clone(r);
r.handlerParams = r.urlExp.exec(url).slice(1);
return r; // .. so return it. We're done
}
if (r.httpMethod === "*") { weakMatch = r; } // Found a weak match
}
}
if (weakMatch) { // Found a weak match. That's good too ..
r = _.clone(weakMatch);
r.handlerParams = r.urlExp.exec(url).slice(1);
return r; // .. so return it. We're done
}
return null;
},
Create route for given name
, urlExp
, httpMethod
and handler
. Will set missing
arguments to defaults and sanitize values where appropriate - note that the only
mandatory argument is urlExp
createRoute = function (name, urlExp, httpMethod, handler) {
var args = skipUndefinedTail(_.toArray(arguments));
switch (args.length) {
Missing name
, handler
or httpMethod
case 3:
Missing name
or httpMethod
if (_.isFunction(args[2])) {
handler = args[2];
Missing name
if (args[1] === "*" || _.contains(crudToHttp, args[1])) {
urlExp = args[0];
httpMethod = args[1];
name = null;
Missing httpMethod
} else {
httpMethod = "*";
}
Missing handler
} else {
handler = noOp;
}
break;
Missing name
& httpMethod
, httpMethod
& handler
or name
& handler
case 2:
Missing name
& httpMethod
if (_.isFunction(args[1])) {
urlExp = args[0];
handler = args[1];
httpMethod = "*";
name = null;
Missing name
& handler
or httpMethod
& handler
} else {
handler = noOp;
Missing name
& handler
if (args[1] === "*" || _.contains(crudToHttp, args[1])) {
urlExp = args[0];
httpMethod = args[1];
name = null;
Missing httpMethod
& handler
} else {
httpMethod = "*";
}
}
break;
Missing name
& httpMethod
& handler
case 1:
urlExp = args[0];
httpMethod = "*";
handler = noOp;
name = null;
break;
case 0:
throw new Error("addRoute: Missing mandatory 'urlExp' argument");
}
httpMethod = httpMethod.toUpperCase();
urlExp = _.isRegExp(urlExp) ? urlExp : makeRegExp(urlExp);
return {
name: name || _.uniqueId(httpMethod + "_" + urlExp + "_"),
urlExp: urlExp,
httpMethod: httpMethod,
handler: handler
};
},
Get the data that should be sent to the server during a sync. This depends on the sync-method being used and any options that may have been given
getRequestData = function (httpMethod, model, options) {
A data
property whithin options overrides any Model data.
if (options.data) { return options.data; }
In the specific case of PATCH, a hash of ‘changed attributes’ is expected within options. If no such thing is present then the complete Model representation will be used instead
if (httpMethod === "PATCH") { return options.attrs || model.toJSON(); }
Send the complete Model representation when POSTing or PUTing
if (httpMethod === "POST" || httpMethod === "PUT") { return model.toJSON(); }
},
Invoked per sync (with the relevant options / context) to create a new transport -
a deferred-like object implementing a promise
/ resolve
/ reject
interface. A
successfull sync will invoke transport.resolve
while a failed one will invoke
transport.reject
. The sync method will always return transport.promise()
createTransport = function (syncOptions /*, syncContext */) {
var success = syncOptions.success || noOp,
error = syncOptions.error || noOp;
If an underlying ajax lib is defined for Backbone (Backbone.$
) and it features a
Deferred
method (which is precisely the case when Backbone.$
= jQuery
) then
attempt to create a ‘deferred transport’ which will invoke the success
/ error
callbacks when its promise is fulfilled / rejected. Note that sync will return the
transport’s promise not the transport itself
if (Backbone.$ && _.isFunction(Backbone.$.Deferred)) {
try {
var deferred = Backbone.$.Deferred();
deferred.then(success, error);
return deferred;
} catch (e) {}
}
Otherwise create a poor-man’s deferred - an object that implements a dumb
promise
/ resolve
/ reject
interface without actual promise semantics:
resolve
and reject
just delegate to success
and error
callbacks while
promise
returns an undefined
. This is a good enough transport
return {
promise: noOp,
resolve: function (value) { success(value); },
reject: function (reason) { error(reason); }
};
};
Replace Backbone’s native sync with faux-server sync:
Backbone.sync = function (crudMethod, model, options) {
If faux-server is disabled, fall back to original sync
if (!isEnabled) { return nativeSync.call(model, crudMethod, model, options); }
_.defaults(options || (options = {}), {
emulateHTTP: Backbone.emulateHTTP,
emulateJSON: Backbone.emulateJSON
});
var
Sync context
ctx = {
data: null,
url: null,
httpMethod: crudToHttp[crudMethod],
route: null
},
An exec-method to actually run the appropriate handler. Defined below
execHandler = null,
We’ll be creating a transport for this sync..
transport = null,
..and returning the transport’s promise
transportPromise = null;
When emulating HTTP, ‘create’, ‘update’, ‘delete’ and ‘patch’ are all mapped to POST.
if (options.emulateHTTP && ctx.httpMethod !== "GET") {
ctx.httpMethodOverride = ctx.httpMethod;
ctx.httpMethod = "POST";
}
Ensure that we have a URL (A url
property whithin options overrides Model /
Collection URL)
if(!(ctx.url = options.url || _.result(model, "url"))) {
throw new Error("sync: Undefined 'url' property or function of Model / Collection");
}
Find route for given URL or fall back to native sync if none found
if (!(ctx.route = getMatchingRoute(ctx.url, ctx.httpMethod) || defaultRoute)) {
return nativeSync.call(model, crudMethod, model, options);
}
Ensure that we have the appropriate request data
ctx.data = getRequestData(ctx.httpMethod, model, options);
Create a transport for this sync
transport = createTransport(options, ctx);
An exec-method to actually run the handler and subsequently invoke success / error callbacks. (The relevant ‘success’ or ‘error’ event will be triggered by backbone)
execHandler = function () {
var result = ctx.route.handler.apply(null, [ctx].concat(ctx.route.handlerParams));
transport[_.isString(result) ? "reject" : "resolve"](result);
};
The transport’s promise to return. Assuming the default transport-factory implementation this may be an actual promise or just undefined
transportPromise = transport.promise();
model.trigger("request", model, transportPromise, options);
Call exec-method asynchronously, taking into account any given latency
_.delay(execHandler, _.isFunction(latency) ? latency(ctx) : latency);
return transportPromise;
};
Extend fauxServer
with the fauxServer API methods:
_.extend(fauxServer, {
Add a route to the faux-server - a mapping from a Model(or Collection)-URL & sync-method
(an HTTP verb (POST, GET, PUT, PATCH or DELETE)) to some specific handler (callback):
<model-URL, sync-method> -> handler
. Whenever a Model is created, read, updated or
deleted, its URL and the the sync method being used will be tested against defined
routes in order to find a handler for creating, reading, updating or deleting this
Model. The same applies to reading Collections. When a match for the setDefaultHandler
). Later routes take
precedence over earlier routes so in configurations where multiple routes match,
the one most recently defined will be used.
The route name
is optional and a named route may be queried and / or removed by its
name. Additionally, a named route will replace an earlier defined route of same name.
The route urlExp
is an expression against which, Model(or Collection)-URLs will be
matched. This is syntactically and functionally analogous to Backbone routes,
featuring parameter parts (‘:param’), splat parts (‘*splat’) and parentheses. The
values captured by params and splats will be passed as parameters to the given handler
method. Regular expressions may also be used, in which case all values captured by
reg-exp capturing groups will be passed as parameters to the given handler method.
Note that :param
s are required to begin with a letter or underscore - those that
don’t are treated as a fixed part of the URL.
The route’s httpMethod
is an HTTP verb (POST, GET, PUT, PATCH or DELETE), that should
trigger the route’s handler. Both the URL-expression and the method should match for
the handler to be invoked. httpMethod may also be set to ‘*’ (or omitted) to create a
match-all-methods handler: One that will be invoked whenever urlExp matches the
model’s (or collection’s) URL regardless of method. In the scope of a
match-all-methods handler, the HTTP method currently being handled may be acquired by
querying the context parameter for context.httpMethod
. Note that when
Backbone.emulateHTTP
is set to true or emulateHTTP
is passed as an inline option
during sync, ‘create’, ‘update’, ‘delete’ and ‘patch’ will all be mapped to POST. In
this case context.httpMethod
will be set to POST and the true HTTP method may be
acquired by querying context.httpMethodOverride
.
The route handler
‘s signature should be
function (context, [param1, [param2, ...]])
where context
contains properties data
, httpMethod
, httpMethodOverride
,
route
and param1
, param2
, … are parameters derived by matching the urlExp
to
the Model (or Collection) URL. Specifically, about context
properties:
context.data
: Attributes of the Model (or Collection) being processed. Valid
only on ‘create’ (POST), ‘update’ (PUT) or ‘patch’ (PATCH). In the specific case of
PATCH, context.data may only contain a subset of Model’s attributes.context.httpMethod
: The HTTP Method (POST, GET, PUT, PATCH, DELETE) that
is currently being handled.context.url
: The URL that is currently being handled.context.httpMethodOverride
: The true HTTP Method (POST, GET, PUT, PATCH, DELETE)
that is currently being handled when Backbone.emulateHTTP is set to true.
The equivalent of Backbone’s X-HTTP-Method-Override header.context.route
: The route that is currently being handled.
On success, the handler should return created Model attributes after handling a POST or updated Model attributes after handling a PUT or PATCH. Return Model attributes after handling a GET or an array of Model attributes after handling a GET that refers to a collection. Note that only attributes that have been changed on the server (and should be updated on the client) need to be included. Return nothing after handling a DELETE. On failure, the handler should return s string (presumably a custom error message, an HTTP status code that indicates failure, etc).
addRoute: function (/* name, urlExp, httpMethod, handler */) {
var route, routeIndex;
Create the route, defaulting and sanitizing where appropriate
route = createRoute.apply(null, arguments);
If a route of given name is already present then overwrite it with this one. Otherwise just append the new route
_.any(routes, function (r, i) {
if (r.name === route.name) {
routeIndex = i;
return true;
}
}) || (routeIndex = routes.length);
routes[routeIndex] = route;
return this;
},
Add multiple routes to faux-server. Given routes
should be a hash or array: In the
case of a hash, keys should be route names and each route (nested hash) need only
contain urlExp
, httpMethod
and handler
. Also see addRoute
. Returns the
faux-server
addRoutes: function (routes) {
var isArray = _.isArray(routes);
_.each(routes, function (r, rName) {
this.addRoute(isArray ? r.name : rName, r.urlExp, r.httpMethod, r.handler);
}, this);
return this;
},
removeRoute: function (routeName) {
routes = _.reject(routes, function (r) { return r.name === routeName; });
return this;
},
removeRoutes: function () {
routes = [];
return this;
},
Get route of given routeName
or null
if no such route exists. Note that the
acquired route is a copy - it cannot be modified to affect faux-server’s behaviour
getRoute: function (routeName) {
var route = _.find(routes, function (r) { return r.name === routeName; });
return route ? _.clone(route) : null;
},
Get route at given index
or null
if no such route exists. Note that the
acquired route is a copy - it cannot be modified to affect faux-server’s behaviour
getRouteAt: function (index) {
return routes[index] ? _.clone(routes[index]) : null;
},
Get route matching the given <url
, httpMethod
> pair or null
if no such route
exists. Note that the acquired route is a copy - it cannot be modified to affect
faux-server’s behaviour. See earlier definition of getMatchingRoute
for details
getMatchingRoute: getMatchingRoute,
Set the given handler
as the one to be invoked when no route is matched to the current
addRoute
for
handler’s signature and semantics. Note that a default-handler isn’t part of a route,
so the context.route
parameter will not be valid. Returns the faux-server
setDefaultHandler: function (handler) {
defaultRoute = !handler ? null : {
name: "",
urlExp: "",
handler: handler,
handlerParams: []
};
return this;
},
Set server’s emulated latency to min
ms or a random latency withing [min
, max
] ms
when the optional max
parameter is given. Omitting both parameters will set latency
to 0. In place of a fixed minimum, a function may also be given that returns a latency.
The function will be invoked per handled route, with the same parameters as those
passed to the relevant route handler (context
, etc). Returns the faux-server
setLatency: function (min, max) {
latency = !max ? (min || 0) : function () { return min + Math.random() * (max - min); };
return this;
},
Set the server’s transport factory - a factory function with signature
function (syncOptions, syncContext)
invoked per sync (with the relevant options / context) to create a new transport - a
deferred-like object implementing a promise
/ resolve
/ reject
interface. A
successfull sync will invoke transport.resolve
while a failed one will invoke
transport.reject
The sync method will always return transport.promise()
. Returns
the faux-server
setTransportFactory: function (factory) {
createTransport = factory;
return this;
},
Enable / disable the faux-server. When disabled, sync will be delegated to the native
backbone sync
. Handy for easily toggling between mock / real server. Set
shouldEnable
to true
or omit altogether to enable, set to false
to disable.
Returns the faux-server
enable: function (shouldEnable) {
isEnabled = _.isUndefined(shouldEnable) || shouldEnable;
return this;
},
getVersion: function () {
return "0.10.5"; // Keep in sync with package.json
}
});
Add a route to the faux-server, for HTTP GET / POST / PUT / PATCH / DEL
Attach <httpMethod>(name, urlExp, handler)
shortcut-methods which delegate to addRoute
_.each(_.values(crudToHttp), function (httpMethod) {
All shortcut-methods are named after the relevant HTTP verb except for ‘delete’ which is abbreviated to ‘del’ to avoid reserved-word trouble
var method = httpMethod === "DELETE" ? "del" : httpMethod.toLowerCase();
fauxServer[method] = function () {
var args = skipUndefinedTail(_.toArray(arguments));
if (!args.length) { throw new Error(method + ": Missing mandatory 'urlExp' argument"); }
The httpMethod
must be inserted into the args, either at tail-position if
handler
is missing or just before it (after urlExp
) if it’s present
if (!_.isFunction(args[args.length - 1])) { args.push(httpMethod); }
else { args.splice(args.length - 1, 0, httpMethod); }
Delegate to addRoute
return fauxServer.addRoute.apply(this, args);
};
});
return fauxServer;
}));