initial stab at creating has_many relationships

lib/waterline/model/index.js

@@ -4,7 +4,8 @@
 
 var _ = require('underscore'),
     Association = require('./association'),
-    extend = require('../utils/extend');
+    extend = require('../utils/extend'),
+    saveInstance = require('./instanceMethods/save');
 
 /**
  * A Basic Model Interface
@@ -131,43 +132,7 @@ Model.inject = function(context, mixins) {
      */
 
     save: function(cb) {
-      var self = this;
-
-      // Collect current values
-      var values = this.toObject();
-
-      // Get primary key attribute
-      var primaryKey;
-
-      Object.keys(context._schema.schema).forEach(function(key) {
-        if(context._schema.schema[key].hasOwnProperty('primaryKey')) {
-          primaryKey = key;
-        }
-      });
-
-      // If no primary key check for an ID property
-      if(!primaryKey && values.hasOwnProperty('id')) primaryKey = 'id';
-
-      if(!primaryKey) return cb(new Error('No Primary Key set to update the record with! ' +
-        'Try setting an attribute as a primary key or include an ID property.'));
-
-      if(!values[primaryKey]) return cb(new Error('No Primary Key set to update the record with! ' +
-        'Primary Key must have a value, it can\'t be an optional value.'));
-
-      // Build Search Criteria
-      var criteria = {};
-      criteria[primaryKey] = values[primaryKey];
-
-      // Execute Query
-      context.update(criteria, values, function(err, model) {
-        if(err) return cb(err);
-
-        // Absorb new values
-        var obj = model[0].toObject();
-        _.extend(self, obj);
-
-        cb(null, self.toObject());
-      });
+      saveInstance.call(this, context, cb);
     },
 
     /**

lib/waterline/model/instanceMethods/save.js

@@ -0,0 +1,164 @@
+var _ = require('underscore'),
+    async = require('async');
+
+/**
+ * Model.save()
+ *
+ * Takes the currently set attributes and updates the database.
+ * Shorthand for Model.update({ attributes }, cb)
+ *
+ * @param {Function} callback
+ * @return callback - (err, results)
+ */
+
+module.exports = function(context, cb) {
+  var self = this;
+
+  // Collect current values
+  var values = self.toObject();
+
+  // Get primary key attribute
+  var primaryKey;
+
+  Object.keys(context._schema.schema).forEach(function(key) {
+    if(context._schema.schema[key].hasOwnProperty('primaryKey')) {
+      primaryKey = key;
+    }
+  });
+
+  // If no primary key check for an ID property
+  if(!primaryKey && values.hasOwnProperty('id')) primaryKey = 'id';
+
+  if(!primaryKey) return cb(new Error('No Primary Key set to update the record with! ' +
+    'Try setting an attribute as a primary key or include an ID property.'));
+
+  if(!values[primaryKey]) return cb(new Error('No Primary Key set to update the record with! ' +
+    'Primary Key must have a value, it can\'t be an optional value.'));
+
+  // Build Search Criteria
+  var criteria = {};
+  criteria[primaryKey] = values[primaryKey];
+
+  // Clone values so they can be mutated
+  var _values = _.clone(values);
+
+  // Remove any association values from the model
+  Object.keys(this.associations).forEach(function(key) {
+    delete _values[key];
+  });
+
+
+  /**
+   * TO-DO:
+   * This should all be wrapped in a transaction. That's coming next but for the meantime
+   * just hope we don't get in a nasty state where the operation fails!
+   */
+
+
+  // Execute Main Update Query
+  context.update(criteria, _values, function(err, model) {
+    if(err) return cb(err);
+
+
+    // Build a set of associations to add and remove
+    var addKeys = {},
+        removeKeys = {};
+
+    Object.keys(self.associations).forEach(function(key) {
+
+      // Grab what records need adding
+      if(self.associations[key].addModels.length > 0) {
+        addKeys[key] = self.associations[key].addModels;
+      }
+
+      // Grab what records need removing
+      if(self.associations[key].removeModels.length > 0) {
+        removeKeys[key] = self.associations[key].removeModels;
+      }
+    });
+
+
+    async.parallel({
+
+      // Add Associations
+      add: function(next) {
+        addAssociation(addKeys, self, context, next);
+      },
+
+      // Remove Associations
+      remove: function(next) {
+        next();
+      }
+    },
+
+    function(err) {
+      if(err) return cb(err);
+
+      // Absorb new values
+      var obj = model[0].toObject();
+      _.extend(self, obj);
+
+      cb(null, self);
+    });
+  });
+};
+
+
+/**
+ * Add an Association
+ *
+ * @param {Array} addKeys
+ * @param {Object} model
+ * @param {Object} context
+ * @param {Function} callback
+ */
+
+function addAssociation(addKeys, model, context, cb) {
+
+  // Loop through each of the associations and add association
+  async.eachSeries(Object.keys(addKeys), function(item, cb1) {
+
+    // Limit Adds to 10 at a time to prevent the connection pool from being
+    // overloaded until we figure out transactions
+    async.eachLimit(addKeys[item], 10, function(association, cb2) {
+      var pk, obj = {}, fk = {};
+
+      // Grab the collection the attribute references
+      // this allows us to make a query on it
+      var attribute = context.attributes[item];
+      var collection = context.collections[attribute.references];
+
+      // Grab the current model's primaryKey
+      Object.keys(context._attributes).forEach(function(key) {
+        if(context._attributes[key].hasOwnProperty('primaryKey')) pk = key;
+      });
+
+      // In order to link a child to this collection a primary key must be defined
+      if(!pk) return cb2(new Error('No primary key found on this model'));
+
+      // If an object was passed in it should be created.
+      // This allows new records to be created through the association interface
+      if(typeof association === 'object' && Object.keys(association).length > 0) {
+        obj = association;
+        obj[attribute.on] = model[pk];
+
+        return collection.create(obj).exec(cb2);
+      }
+
+      // If the value is a primary key just update the association's foreign key
+      // This will either create the new association through a foreign key or re-associatiate
+      // with another collection.
+
+      // Set the primaryKey to use for the update criteria
+      obj[pk] = association;
+
+      // Set the foreignKey value to be updated
+      fk[attribute.on] = model[pk];
+
+      // Run the update method to add the association
+      collection.update(obj, fk).exec(cb2);
+
+    }, cb1);
+
+  }, cb);
+}