Sails.JS - Get the count of the number of objects/rows in the database

TheSharpieOne picture TheSharpieOne · Dec 30, 2013 · Viewed 8.2k times · Source

In Sails.js, a lot of work is done for you by generating the models and controllers. The controllers allow for access to the data through API's. It allows for easy pagination by passing the start/skip/offset and take/limit. But in order for me to determine the maximum page of a collection I need to know how many items are in a collection.

I have tried to extend the blueprint in the generator to expose a new API method count and create the count action. According to the Waterline documentation, count is an action that can be called on the model. When I call User.count(), I get this:

{ _context: 
   { identity: 'user',
     adapter: 
      { syncable: false,
        defaults: [Object],
        registerCollection: [Function],
        create: [Function],
        find: [Function],
        update: [Function],
        destroy: [Function],
        count: [Function],
        identity: 'odata',
        globalId: 'odata',
        config: [Object] },
     attributes: {},
     _cast: { _types: [Object] },
     _schema: { context: [Circular], schema: [Object], hasSchema: true },
     _validator: { validations: {} },
     _callbacks: 
      { beforeValidation: [Object],
        afterValidation: [Object],
        beforeUpdate: [Object],
        afterUpdate: [Object],
        beforeCreate: [Object],
        afterCreate: [Object],
        beforeDestroy: [Object],
        afterDestroy: [Object] },
     _instanceMethods: {},
     autoPK: true,
     autoCreatedAt: true,
     autoUpdatedAt: true,
     hasSchema: true,
     migrate: 'alter',
     _model: { [Function] extend: [Function], inject: [Function], __super__: {} },
     _transformer: { _transformations: {} },
     _tableName: 'user',
     _adapterDefs: [ [Object] ],
     _adapter: 
      { adapter: [Object],
        adapterDefs: [Object],
        query: [Circular],
        collection: 'user' },
     syncable: [Function],
     defaults: [Function],
     registerCollection: [Function],
     config: [Function],
     findOneById: [Function: dynamicMethod],
     findOneByIdIn: [Function: dynamicMethod],
     findOneByIdLike: [Function: dynamicMethod],
     findById: [Function: dynamicMethod],
     findByIdIn: [Function: dynamicMethod],
     findByIdLike: [Function: dynamicMethod],
     countById: [Function: dynamicMethod],
     countByIdIn: [Function: dynamicMethod],
     countByIdLike: [Function: dynamicMethod],
     idStartsWith: [Function: dynamicMethod],
     idContains: [Function: dynamicMethod],
     idEndsWith: [Function: dynamicMethod],
     findOneByCreatedAt: [Function: dynamicMethod],
     findOneByCreatedAtIn: [Function: dynamicMethod],
     findOneByCreatedAtLike: [Function: dynamicMethod],
     findByCreatedAt: [Function: dynamicMethod],
     findByCreatedAtIn: [Function: dynamicMethod],
     findByCreatedAtLike: [Function: dynamicMethod],
     countByCreatedAt: [Function: dynamicMethod],
     countByCreatedAtIn: [Function: dynamicMethod],
     countByCreatedAtLike: [Function: dynamicMethod],
     createdAtStartsWith: [Function: dynamicMethod],
     createdAtContains: [Function: dynamicMethod],
     createdAtEndsWith: [Function: dynamicMethod],
     findOneByUpdatedAt: [Function: dynamicMethod],
     findOneByUpdatedAtIn: [Function: dynamicMethod],
     findOneByUpdatedAtLike: [Function: dynamicMethod],
     findByUpdatedAt: [Function: dynamicMethod],
     findByUpdatedAtIn: [Function: dynamicMethod],
     findByUpdatedAtLike: [Function: dynamicMethod],
     countByUpdatedAt: [Function: dynamicMethod],
     countByUpdatedAtIn: [Function: dynamicMethod],
     countByUpdatedAtLike: [Function: dynamicMethod],
     updatedAtStartsWith: [Function: dynamicMethod],
     updatedAtContains: [Function: dynamicMethod],
     updatedAtEndsWith: [Function: dynamicMethod] },
  _method: [Function],
  _criteria: {},
  _values: null }

Note: I am using a custom adapter, but I have created a count method for the adapter.

Answer

damphat picture damphat · Dec 30, 2013

To get the count of the number of objects in user collection:

User.count(function (err, num) {
    if(err) {
       return console.log(err);
    }
    console.log(num);
});

To wrap User.count in another method:

yourMethod = function (callback) {
    User.count(callback);
}