gocqlx/batchx.go

package gocqlx

import (
	"fmt"

	"github.com/gocql/gocql"
)

// Batch is a wrapper around gocql.Batch
type Batch struct {
	*gocql.Batch
}

// NewBatch creates a new batch operation using defaults defined in the cluster.
func (s *Session) NewBatch(bt gocql.BatchType) *Batch {
	return &Batch{
		Batch: s.Session.NewBatch(bt),
	}
}

// SetHostID allows to define the host the query should be executed against. If the
// host was filtered or otherwise unavailable, then the query will error. If an empty
// string is sent, the default behavior, using the configured HostSelectionPolicy will
// be used. A hostID can be obtained from HostInfo.HostID() after calling GetHosts().
func (b *Batch) SetHostID(hostID string) *Batch {
	b.Batch.SetHostID(hostID)
	return b
}

// BindStruct binds query named parameters to values from arg using a mapper.
// If value cannot be found an error is reported.
func (b *Batch) BindStruct(qry *Queryx, arg interface{}) error {
	args, err := qry.bindStructArgs(arg, nil)
	if err != nil {
		return err
	}
	b.Query(qry.Statement(), args...)
	return nil
}

// Bind binds query parameters to values from args.
// If value cannot be found an error is reported.
func (b *Batch) Bind(qry *Queryx, args ...interface{}) error {
	if len(qry.Names) != len(args) {
		return fmt.Errorf("query requires %d arguments, but %d provided", len(qry.Names), len(args))
	}
	b.Query(qry.Statement(), args...)
	return nil
}

// BindMap binds query named parameters to values from arg using a mapper.
// If value cannot be found an error is reported.
func (b *Batch) BindMap(qry *Queryx, arg map[string]interface{}) error {
	args, err := qry.bindMapArgs(arg)
	if err != nil {
		return err
	}
	b.Query(qry.Statement(), args...)
	return nil
}

// BindStructMap binds query named parameters to values from arg0 and arg1 using a mapper.
// If value cannot be found an error is reported.
func (b *Batch) BindStructMap(qry *Queryx, arg0 interface{}, arg1 map[string]interface{}) error {
	args, err := qry.bindStructArgs(arg0, arg1)
	if err != nil {
		return err
	}
	b.Query(qry.Statement(), args...)
	return nil
}

// ExecuteBatch executes a batch operation and returns nil if successful
// otherwise an error describing the failure.
func (s *Session) ExecuteBatch(batch *Batch) error {
	return s.Session.ExecuteBatch(batch.Batch)
}

// ExecuteBatchCAS executes a batch operation and returns true if successful and
// an iterator (to scan additional rows if more than one conditional statement)
// was sent.
// Further scans on the interator must also remember to include
// the applied boolean as the first argument to *Iter.Scan
func (s *Session) ExecuteBatchCAS(batch *Batch, dest ...interface{}) (applied bool, iter *gocql.Iter, err error) {
	return s.Session.ExecuteBatchCAS(batch.Batch, dest...)
}

// MapExecuteBatchCAS executes a batch operation much like ExecuteBatchCAS,
// however it accepts a map rather than a list of arguments for the initial
// scan.
func (s *Session) MapExecuteBatchCAS(batch *Batch, dest map[string]interface{}) (applied bool, iter *gocql.Iter, err error) {
	return s.Session.MapExecuteBatchCAS(batch.Batch, dest)
}