Documentation
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Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( // MessageStats tracks stats for messages. MessageStats = stats.NewGaugesWithMultiLabels( "Messages", "Stats for messages", []string{"TableName", "Metric"}) )
Functions ¶
This section is empty.
Types ¶
type Engine ¶
type Engine struct {
// contains filtered or unexported fields
}
Engine is the engine for handling messages.
func NewEngine ¶
func NewEngine(tsv TabletService, se *schema.Engine, vs VStreamer) *Engine
NewEngine creates a new Engine.
func (*Engine) GetGenerator ¶ added in v0.12.1
func (me *Engine) GetGenerator(name string) (QueryGenerator, error)
func (*Engine) Subscribe ¶
func (me *Engine) Subscribe(ctx context.Context, name string, send func(*sqltypes.Result) error) (done <-chan struct{}, err error)
Subscribe subscribes to messages from the requested table. The function returns a done channel that will be closed when the subscription ends, which can be initiated by the send function returning io.EOF. The engine can also end a subscription which is usually triggered by Close. It's the responsibility of the send function to promptly return if the done channel is closed. Otherwise, the engine's Close function will hang indefinitely.
type MessageRow ¶
type MessageRow struct {
Priority int64
TimeNext int64
Epoch int64
TimeAcked int64
Row []sqltypes.Value
// contains filtered or unexported fields
}
MessageRow represents a message row. The first column in Row is always the "id".
func BuildMessageRow ¶
func BuildMessageRow(row []sqltypes.Value) (*MessageRow, error)
BuildMessageRow builds a MessageRow from a db row.
type QueryGenerator ¶ added in v0.12.1
type QueryGenerator interface {
GenerateAckQuery(ids []string) (string, map[string]*querypb.BindVariable)
GeneratePostponeQuery(ids []string) (string, map[string]*querypb.BindVariable)
GeneratePurgeQuery(timeCutoff int64) (string, map[string]*querypb.BindVariable)
}
type TabletService ¶
type TabletService interface {
tabletenv.Env
PostponeMessages(ctx context.Context, target *querypb.Target, querygen QueryGenerator, ids []string) (count int64, err error)
PurgeMessages(ctx context.Context, target *querypb.Target, querygen QueryGenerator, timeCutoff int64) (count int64, err error)
}
TabletService defines the functions of TabletServer that the messager needs for callback.
type VStreamer ¶
type VStreamer interface {
Stream(ctx context.Context, startPos string, tablePKs []*binlogdatapb.TableLastPK, filter *binlogdatapb.Filter, throttlerApp throttlerapp.Name, send func([]*binlogdatapb.VEvent) error) error
StreamResults(ctx context.Context, query string, send func(*binlogdatapb.VStreamResultsResponse) error) error
}
VStreamer defines the functions of VStreamer that the messager needs.
Source Files