regard/lib/connectors/mongodb.js

Sugar-interface to access multiple data sources.

var _ = require('lodash'),
    Connector = require('../connector'),
    Monk = require('monk');

exports = module.exports = MongodbConnector;

var Methods = exports.Methods = [
  'index', 'indexes', 'dropIndex', 'dropIndexes',
  'insert',
  'id',
  'find', 'findById', 'findOne', 'findAndModify',
  'remove'
];

var KEY = exports.KEY = Connector.generateKey(__filename);
var SETTINGS = exports.SETTINGS = {
  method: 'find'
};

var dbs = {};

function MongodbConnector() {
  if (!(this instanceof MongodbConnector)) {
    return new MongodbConnector();
  }

  Connector.call(this, KEY, SETTINGS);

  bindHandlers(this);
}

MongodbConnector.prototype = _.create(Connector.prototype);
MongodbConnector.prototype.checkPath = canAcceptPath;
MongodbConnector.prototype.checkMethod = canAcceptMethod;
MongodbConnector.prototype.onCreateEndpoint = createClient;

function bindHandlers($this) {
  $this.handler(Connector.DEFAULT_HANDLER, handleRequest, beforeRequest);
  _.forEach(Methods, function bindHandler(method) {
    $this.handler(method, handleRequest, function beforeHandler(request) {
      return _.partial(beforeRequest, request, method).apply($this, _.slice(arguments, 1));
    });
  });
}

function canAcceptPath(path) {
  return _.startsWith(path, 'mongodb://');
}

function canAcceptMethod(method) {
  return _.isString(method) && _.includes(Methods, method);
}

function createClient(endpoint) {
  var uri = endpoint.path,
      opts = endpoint.context;

  if (endpoint.root) {
    dbs[endpoint.name] = Monk(uri, opts, _.constant());
  } else {
    endpoint.context.collection = collectionNameFromUri(uri);
    dbs[endpoint.name] = dbs[endpoint.parent.name];
  }
}

function beforeRequest(request) {
  var args = _.cloneDeep(_.slice(arguments, 1)),
      method = args.shift(),
      collection;

  if (_.isString(method) && !canAcceptMethod(method)) {
    collection = method;
    method = undefined;
  } else {
    if (_.isString(args[0])) {
      collection = args.shift();
    }
  }

  if (!_.isUndefined(method)) {
    request.context.method = method;
    request.handler = method;
  }

  if (_.isString(collection) && !_.isEmpty(collection)) {
    request.context.collection = collection;
  }

  request.args = args;

  return request;
}

function collectionNameFromUri(uri) {
  return _(uri).split('/').pop();
}

function handleRequest(request, resolve, reject) {
  var db = dbs[request.endpoint.name],
      collection = request.context.collection,
      method = request.handler,
      args = request.args,
      processing;

  collection = db.get(collection);

  processing = _.get(collection, method).apply(collection, args);

  processing.then(resolve, reject);
}