fix golint issues in core/stores (#527)

core/stores/mongo/model.go

@@ -12,8 +12,10 @@ type (
 		timeout time.Duration
 	}
 
+	// Option defines the method to customize a mongo model.
 	Option func(opts *options)
 
+	// A Model is a mongo model.
 	Model struct {
 		session    *concurrentSession
 		db         *mgo.Database
@@ -22,6 +24,7 @@ type (
 	}
 )
 
+// MustNewModel returns a Model, exits on errors.
 func MustNewModel(url, collection string, opts ...Option) *Model {
 	model, err := NewModel(url, collection, opts...)
 	if err != nil {
@@ -31,6 +34,7 @@ func MustNewModel(url, collection string, opts ...Option) *Model {
 	return model
 }
 
+// NewModel returns a Model.
 func NewModel(url, collection string, opts ...Option) (*Model, error) {
 	session, err := getConcurrentSession(url)
 	if err != nil {
@@ -46,72 +50,85 @@ func NewModel(url, collection string, opts ...Option) (*Model, error) {
 	}, nil
 }
 
+// Find finds a record with given query.
 func (mm *Model) Find(query interface{}) (Query, error) {
 	return mm.query(func(c Collection) Query {
 		return c.Find(query)
 	})
 }
 
+// FindId finds a record with given id.
 func (mm *Model) FindId(id interface{}) (Query, error) {
 	return mm.query(func(c Collection) Query {
 		return c.FindId(id)
 	})
 }
 
+// GetCollection returns a Collection with given session.
 func (mm *Model) GetCollection(session *mgo.Session) Collection {
 	return newCollection(mm.db.C(mm.collection).With(session))
 }
 
+// Insert inserts docs into mm.
 func (mm *Model) Insert(docs ...interface{}) error {
 	return mm.execute(func(c Collection) error {
 		return c.Insert(docs...)
 	})
 }
 
+// Pipe returns a Pipe with given pipeline.
 func (mm *Model) Pipe(pipeline interface{}) (Pipe, error) {
 	return mm.pipe(func(c Collection) Pipe {
 		return c.Pipe(pipeline)
 	})
 }
 
+// PutSession returns the given session.
 func (mm *Model) PutSession(session *mgo.Session) {
 	mm.session.putSession(session)
 }
 
+// Remove removes the records with given selector.
 func (mm *Model) Remove(selector interface{}) error {
 	return mm.execute(func(c Collection) error {
 		return c.Remove(selector)
 	})
 }
 
+// RemoveAll removes all with given selector and returns a mgo.ChangeInfo.
 func (mm *Model) RemoveAll(selector interface{}) (*mgo.ChangeInfo, error) {
 	return mm.change(func(c Collection) (*mgo.ChangeInfo, error) {
 		return c.RemoveAll(selector)
 	})
 }
 
+// RemoveId removes a record with given id.
 func (mm *Model) RemoveId(id interface{}) error {
 	return mm.execute(func(c Collection) error {
 		return c.RemoveId(id)
 	})
 }
 
+// TakeSession gets a session.
 func (mm *Model) TakeSession() (*mgo.Session, error) {
 	return mm.session.takeSession(mm.opts...)
 }
 
+// Update updates a record with given selector.
 func (mm *Model) Update(selector, update interface{}) error {
 	return mm.execute(func(c Collection) error {
 		return c.Update(selector, update)
 	})
 }
 
+// UpdateId updates a record with given id.
 func (mm *Model) UpdateId(id, update interface{}) error {
 	return mm.execute(func(c Collection) error {
 		return c.UpdateId(id, update)
 	})
 }
 
+// Upsert upserts a record with given selector, and returns a mgo.ChangeInfo.
 func (mm *Model) Upsert(selector, update interface{}) (*mgo.ChangeInfo, error) {
 	return mm.change(func(c Collection) (*mgo.ChangeInfo, error) {
 		return c.Upsert(selector, update)
@@ -158,6 +175,7 @@ func (mm *Model) query(fn func(c Collection) Query) (Query, error) {
 	return fn(mm.GetCollection(session)), nil
 }
 
+// WithTimeout customizes an operation with given timeout.
 func WithTimeout(timeout time.Duration) Option {
 	return func(opts *options) {
 		opts.timeout = timeout