// Copyright IBM Corp. 2014,2016. All Rights Reserved.
// Node module: loopback
// This file is licensed under the MIT License.
// License text available at https://opensource.org/licenses/MIT
/*!
* Module Dependencies.
*/
var g = require('strong-globalize')();
var assert = require('assert');
var debug = require('debug')('loopback:model');
var RemoteObjects = require('strong-remoting');
var SharedClass = require('strong-remoting').SharedClass;
var extend = require('util')._extend;
var format = require('util').format;
module.exports = function(registry) {
/**
* The base class for **all models**.
*
* **Inheriting from `Model`**
*
* ```js
* var properties = {...};
* var options = {...};
* var MyModel = loopback.Model.extend('MyModel', properties, options);
* ```
*
* **Options**
*
* - `trackChanges` - If true, changes to the model will be tracked. **Required
* for replication.**
*
* **Events**
*
* #### Event: `changed`
*
* Emitted after a model has been successfully created, saved, or updated.
* Argument: `inst`, model instance, object
*
* ```js
* MyModel.on('changed', function(inst) {
* console.log('model with id %s has been changed', inst.id);
* // => model with id 1 has been changed
* });
* ```
*
* #### Event: `deleted`
*
* Emitted after an individual model has been deleted.
* Argument: `id`, model ID (number).
*
* ```js
* MyModel.on('deleted', function(id) {
* console.log('model with id %s has been deleted', id);
* // => model with id 1 has been deleted
* });
* ```
*
* #### Event: `deletedAll`
*
* Emitted after an individual model has been deleted.
* Argument: `where` (optional), where filter, JSON object.
*
* ```js
* MyModel.on('deletedAll', function(where) {
* if (where) {
* console.log('all models where ', where, ' have been deleted');
* // => all models where
* // => {price: {gt: 100}}
* // => have been deleted
* }
* });
* ```
*
* #### Event: `attached`
*
* Emitted after a `Model` has been attached to an `app`.
*
* #### Event: `dataSourceAttached`
*
* Emitted after a `Model` has been attached to a `DataSource`.
*
* #### Event: set
*
* Emitted when model property is set.
* Argument: `inst`, model instance, object
*
* ```js
* MyModel.on('set', function(inst) {
* console.log('model with id %s has been changed', inst.id);
* // => model with id 1 has been changed
* });
* ```
*
* @param {Object} data
* @property {String} Model.modelName The name of the model. Static property.
* @property {DataSource} Model.dataSource Data source to which the model is connected, if any. Static property.
* @property {SharedClass} Model.sharedMethod The `strong-remoting` [SharedClass](http://apidocs.strongloop.com/strong-remoting/#sharedclass) that contains remoting (and http) metadata. Static property.
* @property {Object} settings Contains additional model settings.
* @property {string} settings.http.path Base URL of the model HTTP route.
* @property [{string}] settings.acls Array of ACLs for the model.
* @class
*/
var Model = registry.modelBuilder.define('Model');
Model.registry = registry;
/**
* The `loopback.Model.extend()` method calls this when you create a model that extends another model.
* Add any setup or configuration code you want executed when the model is created.
* See [Setting up a custom model](http://docs.strongloop.com/display/LB/Extending+built-in+models#Extendingbuilt-inmodels-Settingupacustommodel).
*/
Model.setup = function() {
var ModelCtor = this;
var Parent = this.super_;
if (!ModelCtor.registry && Parent && Parent.registry) {
ModelCtor.registry = Parent.registry;
}
var options = this.settings;
var typeName = this.modelName;
// support remoting prototype methods
// it's important to setup this function *before* calling `new SharedClass`
// otherwise remoting metadata from our base model is picked up
ModelCtor.sharedCtor = function(data, id, options, fn) {
var ModelCtor = this;
var isRemoteInvocationWithOptions = typeof data !== 'object' &&
typeof id === 'object' &&
typeof options === 'function';
if (isRemoteInvocationWithOptions) {
// sharedCtor(id, options, fn)
fn = options;
options = id;
id = data;
data = null;
} else if (typeof data === 'function') {
// sharedCtor(fn)
fn = data;
data = null;
id = null;
options = null;
} else if (typeof id === 'function') {
// sharedCtor(data, fn)
// sharedCtor(id, fn)
fn = id;
options = null;
if (typeof data !== 'object') {
id = data;
data = null;
} else {
id = null;
}
}
if (id != null && data) {
var model = new ModelCtor(data);
model.id = id;
fn(null, model);
} else if (data) {
fn(null, new ModelCtor(data));
} else if (id != null) {
var filter = {};
ModelCtor.findById(id, filter, options, function(err, model) {
if (err) {
fn(err);
} else if (model) {
fn(null, model);
} else {
err = new Error(g.f('could not find a model with {{id}} %s', id));
err.statusCode = 404;
err.code = 'MODEL_NOT_FOUND';
fn(err);
}
});
} else {
fn(new Error(g.f('must specify an {{id}} or {{data}}')));
}
};
var idDesc = ModelCtor.modelName + ' id';
ModelCtor.sharedCtor.accepts = this._removeOptionsArgIfDisabled([
{arg: 'id', type: 'any', required: true, http: {source: 'path'},
description: idDesc},
// {arg: 'instance', type: 'object', http: {source: 'body'}}
{arg: 'options', type: 'object', http: createOptionsViaModelMethod},
]);
ModelCtor.sharedCtor.http = [
{path: '/:id'}
];
ModelCtor.sharedCtor.returns = {root: true};
var remotingOptions = {};
extend(remotingOptions, options.remoting || {});
// create a sharedClass
var sharedClass = ModelCtor.sharedClass = new SharedClass(
ModelCtor.modelName,
ModelCtor,
remotingOptions
);
// setup a remoting type converter for this model
RemoteObjects.convert(typeName, function(val) {
return val ? new ModelCtor(val) : val;
});
// before remote hook
ModelCtor.beforeRemote = function(name, fn) {
var className = this.modelName;
this._runWhenAttachedToApp(function(app) {
var remotes = app.remotes();
remotes.before(className + '.' + name, function(ctx, next) {
return fn(ctx, ctx.result, next);
});
});
};
// after remote hook
ModelCtor.afterRemote = function(name, fn) {
var className = this.modelName;
this._runWhenAttachedToApp(function(app) {
var remotes = app.remotes();
remotes.after(className + '.' + name, function(ctx, next) {
return fn(ctx, ctx.result, next);
});
});
};
ModelCtor.afterRemoteError = function(name, fn) {
var className = this.modelName;
this._runWhenAttachedToApp(function(app) {
var remotes = app.remotes();
remotes.afterError(className + '.' + name, fn);
});
};
ModelCtor._runWhenAttachedToApp = function(fn) {
if (this.app) return fn(this.app);
var self = this;
self.once('attached', function() {
fn(self.app);
});
};
// resolve relation functions
sharedClass.resolve(function resolver(define) {
var relations = ModelCtor.relations || {};
var defineRaw = define;
define = function(name, options, fn) {
if (options.accepts) {
options = extend({}, options);
options.accepts = setupOptionsArgs(options.accepts);
}
defineRaw(name, options, fn);
};
// get the relations
for (var relationName in relations) {
var relation = relations[relationName];
if (relation.type === 'belongsTo') {
ModelCtor.belongsToRemoting(relationName, relation, define);
} else if (
relation.type === 'hasOne' ||
relation.type === 'embedsOne'
) {
ModelCtor.hasOneRemoting(relationName, relation, define);
} else if (
relation.type === 'hasMany' ||
relation.type === 'embedsMany' ||
relation.type === 'referencesMany') {
ModelCtor.hasManyRemoting(relationName, relation, define);
}
}
// handle scopes
var scopes = ModelCtor.scopes || {};
for (var scopeName in scopes) {
ModelCtor.scopeRemoting(scopeName, scopes[scopeName], define);
}
});
return ModelCtor;
};
/*!
* Get the reference to ACL in a lazy fashion to avoid race condition in require
*/
var _aclModel = null;
Model._ACL = function getACL(ACL) {
var registry = this.registry;
if (ACL !== undefined) {
// The function is used as a setter
_aclModel = ACL;
}
if (_aclModel) {
return _aclModel;
}
var aclModel = registry.getModel('ACL');
_aclModel = registry.getModelByType(aclModel);
return _aclModel;
};
/**
* Check if the given access token can invoke the specified method.
*
* @param {AccessToken} token The access token.
* @param {*} modelId The model ID.
* @param {SharedMethod} sharedMethod The method in question.
* @param {Object} ctx The remote invocation context.
* @callback {Function} callback The callback function.
* @param {String|Error} err The error object.
* @param {Boolean} allowed True if the request is allowed; false otherwise.
*/
Model.checkAccess = function(token, modelId, sharedMethod, ctx, callback) {
var ANONYMOUS = registry.getModel('AccessToken').ANONYMOUS;
token = token || ANONYMOUS;
var aclModel = Model._ACL();
ctx = ctx || {};
if (typeof ctx === 'function' && callback === undefined) {
callback = ctx;
ctx = {};
}
aclModel.checkAccessForContext({
accessToken: token,
model: this,
property: sharedMethod.name,
method: sharedMethod.name,
sharedMethod: sharedMethod,
modelId: modelId,
accessType: this._getAccessTypeForMethod(sharedMethod),
remotingContext: ctx
}, function(err, accessRequest) {
if (err) return callback(err);
callback(null, accessRequest.isAllowed());
});
};
/*!
* Determine the access type for the given `RemoteMethod`.
*
* @api private
* @param {RemoteMethod} method
*/
Model._getAccessTypeForMethod = function(method) {
if (typeof method === 'string') {
method = {name: method};
}
assert(
typeof method === 'object',
'method is a required argument and must be a RemoteMethod object'
);
var ACL = Model._ACL();
// Check the explicit setting of accessType
if (method.accessType) {
assert(method.accessType === ACL.READ ||
method.accessType === ACL.REPLICATE ||
method.accessType === ACL.WRITE ||
method.accessType === ACL.EXECUTE, 'invalid accessType ' +
method.accessType +
'. It must be "READ", "REPLICATE", "WRITE", or "EXECUTE"');
return method.accessType;
}
// Default GET requests to READ
var verb = method.http && method.http.verb;
if (typeof verb === 'string') {
verb = verb.toUpperCase();
}
if (verb === 'GET' || verb === 'HEAD') {
return ACL.READ;
}
switch (method.name) {
case'create':
return ACL.WRITE;
case 'updateOrCreate':
return ACL.WRITE;
case 'upsertWithWhere':
return ACL.WRITE;
case 'upsert':
return ACL.WRITE;
case 'exists':
return ACL.READ;
case 'findById':
return ACL.READ;
case 'find':
return ACL.READ;
case 'findOne':
return ACL.READ;
case 'destroyById':
return ACL.WRITE;
case 'deleteById':
return ACL.WRITE;
case 'removeById':
return ACL.WRITE;
case 'count':
return ACL.READ;
default:
return ACL.EXECUTE;
}
};
/**
* Get the `Application` object to which the Model is attached.
*
* @callback {Function} callback Callback function called with `(err, app)` arguments.
* @param {Error} err Error object; see [Error object](http://docs.strongloop.com/display/LB/Error+object).
* @param {Application} app Attached application object.
* @end
*/
Model.getApp = function(callback) {
var self = this;
self._runWhenAttachedToApp(function(app) {
assert(self.app);
assert.equal(app, self.app);
callback(null, app);
});
};
/**
* Enable remote invocation for the specified method.
* See [Remote methods](http://docs.strongloop.com/display/LB/Remote+methods) for more information.
*
* Static method example:
* ```js
* Model.myMethod();
* Model.remoteMethod('myMethod');
* ```
*
* @param {String} name The name of the method.
* @param {Object} options The remoting options.
* See [Remote methods - Options](http://docs.strongloop.com/display/LB/Remote+methods#Remotemethods-Options).
*/
Model.remoteMethod = function(name, options) {
if (options.isStatic === undefined) {
options.isStatic = true;
}
if (options.accepts) {
options = extend({}, options);
options.accepts = setupOptionsArgs(options.accepts);
}
this.sharedClass.defineMethod(name, options);
};
function setupOptionsArgs(accepts) {
if (!Array.isArray(accepts))
accepts = [accepts];
return accepts.map(function(arg) {
if (arg.http && arg.http === 'optionsFromRequest') {
// clone to preserve the input value
arg = extend({}, arg);
arg.http = createOptionsViaModelMethod;
}
return arg;
});
}
function createOptionsViaModelMethod(ctx) {
var EMPTY_OPTIONS = {};
var ModelCtor = ctx.method && ctx.method.ctor;
if (!ModelCtor)
return EMPTY_OPTIONS;
if (typeof ModelCtor.createOptionsFromRemotingContext !== 'function')
return EMPTY_OPTIONS;
debug('createOptionsFromRemotingContext for %s', ctx.method.stringName);
return ModelCtor.createOptionsFromRemotingContext(ctx);
}
/**
* Disable remote invocation for the method with the given name.
*
* @param {String} name The name of the method.
* @param {Boolean} isStatic Is the method static (eg. `MyModel.myMethod`)? Pass
* `false` if the method defined on the prototype (eg.
* `MyModel.prototype.myMethod`).
*/
Model.disableRemoteMethod = function(name, isStatic) {
var key = this.sharedClass.getKeyFromMethodNameAndTarget(name, isStatic);
this.sharedClass.disableMethodByName(key);
this.emit('remoteMethodDisabled', this.sharedClass, key);
};
/**
* Disable remote invocation for the method with the given name.
*
* @param {String} name The name of the method (include "prototype." if the method is defined on the prototype).
*
*/
Model.disableRemoteMethodByName = function(name) {
this.sharedClass.disableMethodByName(name);
this.emit('remoteMethodDisabled', this.sharedClass, name);
};
Model.belongsToRemoting = function(relationName, relation, define) {
var modelName = relation.modelTo && relation.modelTo.modelName;
modelName = modelName || 'PersistedModel';
var fn = this.prototype[relationName];
var pathName = (relation.options.http && relation.options.http.path) || relationName;
define('__get__' + relationName, {
isStatic: false,
http: {verb: 'get', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{arg: 'refresh', type: 'boolean', http: {source: 'query'}},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
accessType: 'READ',
description: format('Fetches belongsTo relation %s.', relationName),
returns: {arg: relationName, type: modelName, root: true},
}, fn);
};
function convertNullToNotFoundError(toModelName, ctx, cb) {
if (ctx.result !== null) return cb();
var fk = ctx.getArgByName('fk');
var msg = g.f('Unknown "%s" id "%s".', toModelName, fk);
var error = new Error(msg);
error.statusCode = error.status = 404;
error.code = 'MODEL_NOT_FOUND';
cb(error);
}
Model.hasOneRemoting = function(relationName, relation, define) {
var pathName = (relation.options.http && relation.options.http.path) || relationName;
var toModelName = relation.modelTo.modelName;
define('__get__' + relationName, {
isStatic: false,
http: {verb: 'get', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{arg: 'refresh', type: 'boolean', http: {source: 'query'}},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Fetches hasOne relation %s.', relationName),
accessType: 'READ',
returns: {arg: relationName, type: relation.modelTo.modelName, root: true},
rest: {after: convertNullToNotFoundError.bind(null, toModelName)}
});
define('__create__' + relationName, {
isStatic: false,
http: {verb: 'post', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'data', type: 'object', model: toModelName,
http: {source: 'body'},
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Creates a new instance in %s of this model.', relationName),
accessType: 'WRITE',
returns: {arg: 'data', type: toModelName, root: true}
});
define('__update__' + relationName, {
isStatic: false,
http: {verb: 'put', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'data', type: 'object', model: toModelName,
http: {source: 'body'},
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Update %s of this model.', relationName),
accessType: 'WRITE',
returns: {arg: 'data', type: toModelName, root: true}
});
define('__destroy__' + relationName, {
isStatic: false,
http: {verb: 'delete', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Deletes %s of this model.', relationName),
accessType: 'WRITE',
});
};
Model.hasManyRemoting = function(relationName, relation, define) {
var pathName = (relation.options.http && relation.options.http.path) || relationName;
var toModelName = relation.modelTo.modelName;
var findByIdFunc = this.prototype['__findById__' + relationName];
define('__findById__' + relationName, {
isStatic: false,
http: {verb: 'get', path: '/' + pathName + '/:fk'},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'fk', type: 'any',
description: format('Foreign key for %s', relationName),
required: true,
http: {source: 'path'},
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Find a related item by id for %s.', relationName),
accessType: 'READ',
returns: {arg: 'result', type: toModelName, root: true},
rest: {after: convertNullToNotFoundError.bind(null, toModelName)}
}, findByIdFunc);
var destroyByIdFunc = this.prototype['__destroyById__' + relationName];
define('__destroyById__' + relationName, {
isStatic: false,
http: {verb: 'delete', path: '/' + pathName + '/:fk'},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'fk', type: 'any',
description: format('Foreign key for %s', relationName),
required: true,
http: {source: 'path'},
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Delete a related item by id for %s.', relationName),
accessType: 'WRITE',
returns: []
}, destroyByIdFunc);
var updateByIdFunc = this.prototype['__updateById__' + relationName];
define('__updateById__' + relationName, {
isStatic: false,
http: {verb: 'put', path: '/' + pathName + '/:fk'},
accepts: this._removeOptionsArgIfDisabled([
{arg: 'fk', type: 'any',
description: format('Foreign key for %s', relationName),
required: true,
http: { source: 'path' }},
{arg: 'data', type: 'object', model: toModelName, http: {source: 'body'}},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Update a related item by id for %s.', relationName),
accessType: 'WRITE',
returns: {arg: 'result', type: toModelName, root: true}
}, updateByIdFunc);
if (relation.modelThrough || relation.type === 'referencesMany') {
var modelThrough = relation.modelThrough || relation.modelTo;
var accepts = [];
if (relation.type === 'hasMany' && relation.modelThrough) {
// Restrict: only hasManyThrough relation can have additional properties
accepts.push({arg: 'data', type: 'object', model: modelThrough.modelName, http: {source: 'body'}});
}
var addFunc = this.prototype['__link__' + relationName];
define('__link__' + relationName, {
isStatic: false,
http: {verb: 'put', path: '/' + pathName + '/rel/:fk'},
accepts: [{ arg: 'fk', type: 'any',
description: format('Foreign key for %s', relationName),
required: true,
http: {source: 'path'}},
].concat(accepts).concat(this._removeOptionsArgIfDisabled([
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
])),
description: format('Add a related item by id for %s.', relationName),
accessType: 'WRITE',
returns: {arg: relationName, type: modelThrough.modelName, root: true}
}, addFunc);
var removeFunc = this.prototype['__unlink__' + relationName];
define('__unlink__' + relationName, {
isStatic: false,
http: {verb: 'delete', path: '/' + pathName + '/rel/:fk'},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'fk', type: 'any',
description: format('Foreign key for %s', relationName),
required: true,
http: {source: 'path'},
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Remove the %s relation to an item by id.', relationName),
accessType: 'WRITE',
returns: []
}, removeFunc);
// FIXME: [rfeng] How to map a function with callback(err, true|false) to HEAD?
// true --> 200 and false --> 404?
var existsFunc = this.prototype['__exists__' + relationName];
define('__exists__' + relationName, {
isStatic: false,
http: {verb: 'head', path: '/' + pathName + '/rel/:fk'},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'fk', type: 'any',
description: format('Foreign key for %s', relationName),
required: true,
http: {source: 'path'},
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Check the existence of %s relation to an item by id.', relationName),
accessType: 'READ',
returns: {arg: 'exists', type: 'boolean', root: true},
rest: {
// After hook to map exists to 200/404 for HEAD
after: function(ctx, cb) {
if (ctx.result === false) {
var modelName = ctx.method.sharedClass.name;
var id = ctx.getArgByName('id');
var msg = g.f('Unknown "%s" {{id}} "%s".', modelName, id);
var error = new Error(msg);
error.statusCode = error.status = 404;
error.code = 'MODEL_NOT_FOUND';
cb(error);
} else {
cb();
}
}
}
}, existsFunc);
}
};
Model.scopeRemoting = function(scopeName, scope, define) {
var pathName =
(scope.options && scope.options.http && scope.options.http.path) || scopeName;
var isStatic = scope.isStatic;
var toModelName = scope.modelTo.modelName;
// https://github.com/strongloop/loopback/issues/811
// Check if the scope is for a hasMany relation
var relation = this.relations[scopeName];
if (relation && relation.modelTo) {
// For a relation with through model, the toModelName should be the one
// from the target model
toModelName = relation.modelTo.modelName;
}
define('__get__' + scopeName, {
isStatic: isStatic,
http: {verb: 'get', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{arg: 'filter', type: 'object'},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Queries %s of %s.', scopeName, this.modelName),
accessType: 'READ',
returns: {arg: scopeName, type: [toModelName], root: true}
});
define('__create__' + scopeName, {
isStatic: isStatic,
http: {verb: 'post', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'data',
type: 'object',
model: toModelName,
http: {source: 'body'},
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Creates a new instance in %s of this model.', scopeName),
accessType: 'WRITE',
returns: {arg: 'data', type: toModelName, root: true}
});
define('__delete__' + scopeName, {
isStatic: isStatic,
http: {verb: 'delete', path: '/' + pathName},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'where', type: 'object',
// The "where" argument is not exposed in the REST API
// but we need to provide a value so that we can pass "options"
// as the third argument.
http: function(ctx) { return undefined; },
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Deletes all %s of this model.', scopeName),
accessType: 'WRITE',
});
define('__count__' + scopeName, {
isStatic: isStatic,
http: {verb: 'get', path: '/' + pathName + '/count'},
accepts: this._removeOptionsArgIfDisabled([
{
arg: 'where', type: 'object',
description: 'Criteria to match model instances',
},
{arg: 'options', type: 'object', http: 'optionsFromRequest'},
]),
description: format('Counts %s of %s.', scopeName, this.modelName),
accessType: 'READ',
returns: {arg: 'count', type: 'number'}
});
};
Model._removeOptionsArgIfDisabled = function(accepts) {
if (this.settings.injectOptionsFromRemoteContext)
return accepts;
var lastArg = accepts[accepts.length - 1];
var hasOptions = lastArg.arg === 'options' && lastArg.type === 'object';
assert(hasOptions, 'last accepts argument is "options" arg');
return accepts.slice(0, -1);
};
/**
* Enabled deeply-nested queries of related models via REST API.
*
* @param {String} relationName Name of the nested relation.
* @options {Object} [options] It is optional. See below.
* @param {String} pathName The HTTP path (relative to the model) at which your remote method is exposed.
* @param {String} filterMethod The filter name.
* @param {String} paramName The argument name that the remote method accepts.
* @param {String} getterName The getter name.
* @param {Boolean} hooks Whether to inherit before/after hooks.
* @callback {Function} filterCallback The Optional filter function.
* @param {Object} SharedMethod object. See [here](https://apidocs.strongloop.com/strong-remoting/#sharedmethod).
* @param {Object} RelationDefinition object which includes relation `type`, `ModelConstructor` of `modelFrom`, `modelTo`, `keyFrom`, `keyTo` and more relation definitions.
*/
Model.nestRemoting = function(relationName, options, filterCallback) {
if (typeof options === 'function' && !filterCallback) {
filterCallback = options;
options = {};
}
options = options || {};
var regExp = /^__([^_]+)__([^_]+)$/;
var relation = this.relations[relationName];
if (relation && relation.modelTo && relation.modelTo.sharedClass) {
var self = this;
var sharedClass = this.sharedClass;
var sharedToClass = relation.modelTo.sharedClass;
var toModelName = relation.modelTo.modelName;
var pathName = options.pathName || relation.options.path || relationName;
var paramName = options.paramName || 'nk';
var http = [].concat(sharedToClass.http || [])[0];
var httpPath;
var acceptArgs;
if (relation.multiple) {
httpPath = pathName + '/:' + paramName;
acceptArgs = [
{
arg: paramName, type: 'any', http: { source: 'path' },
description: format('Foreign key for %s.', relation.name),
required: true,
},
];
} else {
httpPath = pathName;
acceptArgs = [];
}
if (httpPath[0] !== '/') {
httpPath = '/' + httpPath;
}
// A method should return the method name to use, if it is to be
// included as a nested method - a falsy return value will skip.
var filter = filterCallback || options.filterMethod || function(method, relation) {
var matches = method.name.match(regExp);
if (matches) {
return '__' + matches[1] + '__' + relation.name + '__' + matches[2];
}
};
sharedToClass.methods().forEach(function(method) {
var methodName;
if (!method.isStatic && (methodName = filter(method, relation))) {
var prefix = relation.multiple ? '__findById__' : '__get__';
var getterName = options.getterName || (prefix + relationName);
var getterFn = relation.modelFrom.prototype[getterName];
if (typeof getterFn !== 'function') {
throw new Error(g.f('Invalid remote method: `%s`', getterName));
}
var nestedFn = relation.modelTo.prototype[method.name];
if (typeof nestedFn !== 'function') {
throw new Error(g.f('Invalid remote method: `%s`', method.name));
}
var opts = {};
opts.accepts = acceptArgs.concat(method.accepts || []);
opts.returns = [].concat(method.returns || []);
opts.description = method.description;
opts.accessType = method.accessType;
opts.rest = extend({}, method.rest || {});
opts.rest.delegateTo = method;
opts.http = [];
var routes = [].concat(method.http || []);
routes.forEach(function(route) {
if (route.path) {
var copy = extend({}, route);
copy.path = httpPath + route.path;
opts.http.push(copy);
}
});
if (relation.multiple) {
sharedClass.defineMethod(methodName, opts, function(fkId) {
var args = Array.prototype.slice.call(arguments, 1);
var last = args[args.length - 1];
var cb = typeof last === 'function' ? last : null;
this[getterName](fkId, function(err, inst) {
if (err && cb) return cb(err);
if (inst instanceof relation.modelTo) {
try {
nestedFn.apply(inst, args);
} catch (err) {
if (cb) return cb(err);
}
} else if (cb) {
cb(err, null);
}
});
}, method.isStatic);
} else {
sharedClass.defineMethod(methodName, opts, function() {
var args = Array.prototype.slice.call(arguments);
var last = args[args.length - 1];
var cb = typeof last === 'function' ? last : null;
this[getterName](function(err, inst) {
if (err && cb) return cb(err);
if (inst instanceof relation.modelTo) {
try {
nestedFn.apply(inst, args);
} catch (err) {
if (cb) return cb(err);
}
} else if (cb) {
cb(err, null);
}
});
}, method.isStatic);
}
}
});
if (options.hooks === false) return; // don't inherit before/after hooks
self.once('mounted', function(app, sc, remotes) {
var listenerTree = extend({}, remotes.listenerTree || {});
listenerTree.before = listenerTree.before || {};
listenerTree.after = listenerTree.after || {};
var beforeListeners = listenerTree.before[toModelName] || {};
var afterListeners = listenerTree.after[toModelName] || {};
sharedClass.methods().forEach(function(method) {
var delegateTo = method.rest && method.rest.delegateTo;
if (delegateTo && delegateTo.ctor == relation.modelTo) {
var before = method.isStatic ? beforeListeners : beforeListeners['prototype'];
var after = method.isStatic ? afterListeners : afterListeners['prototype'];
var m = method.isStatic ? method.name : 'prototype.' + method.name;
if (before && before[delegateTo.name]) {
self.beforeRemote(m, function(ctx, result, next) {
before[delegateTo.name]._listeners.call(null, ctx, next);
});
}
if (after && after[delegateTo.name]) {
self.afterRemote(m, function(ctx, result, next) {
after[delegateTo.name]._listeners.call(null, ctx, next);
});
}
}
});
});
} else {
var msg = g.f('Relation `%s` does not exist for model `%s`', relationName, this.modelName);
throw new Error(msg);
}
};
Model.ValidationError = require('loopback-datasource-juggler').ValidationError;
/**
* Create "options" value to use when invoking model methods
* via strong-remoting (e.g. REST).
*
* Example
*
* ```js
* MyModel.myMethod = function(options, cb) {
* // by default, options contains only one property "accessToken"
* var accessToken = options && options.accessToken;
* var userId = accessToken && accessToken.userId;
* var message = 'Hello ' + (userId ? 'user #' + userId : 'anonymous');
* cb(null, message);
* });
*
* MyModel.remoteMethod('myMethod', {
* accepts: {
* arg: 'options',
* type: 'object',
* // "optionsFromRequest" is a loopback-specific HTTP mapping that
* // calls Model's createOptionsFromRemotingContext
* // to build the argument value
* http: 'optionsFromRequest'
* },
* returns: {
* arg: 'message',
* type: 'string'
* }
* });
* ```
*
* @param {Object} ctx A strong-remoting Context instance
* @returns {Object} The value to pass to "options" argument.
*/
Model.createOptionsFromRemotingContext = function(ctx) {
return {
accessToken: ctx.req.accessToken,
};
};
// setup the initial model
Model.setup();
return Model;
};