kafka

Documentation

Overview

Package kafka is the most complex backend as it has several different operating modes. Due to this, it should not be used as a "template" for other backends - most other backends are significantly simpler and follow an expected flow.

Index

• Constants
• Variables
• func ConnectAllTopics(dialer *skafka.Dialer, connArgs *args.KafkaConn, topics []string) (map[string]*skafka.Conn, error)
• func NewReaderForRead(dialer *skafka.Dialer, connArgs *args.KafkaConn, readArgs *args.KafkaReadArgs) (*skafka.Reader, error)
• func NewReaderForRelay(dialer *skafka.Dialer, connArgs *args.KafkaConn, ...) (*skafka.Reader, error)
• func NewWriter(dialer *skafka.Dialer, connArgs *args.KafkaConn, topics ...string) (*skafka.Writer, error)
• type Kafka
  • func New(connOpts *opts.ConnectionOptions) (*Kafka, error)
  • func (k *Kafka) Close(_ context.Context) error
  • func (k *Kafka) DisplayError(msg *records.ErrorRecord) error
  • func (k *Kafka) DisplayMessage(cliOpts *opts.CLIOptions, msg *records.ReadRecord) error
  • func (k *Kafka) Dynamic(ctx context.Context, opts *opts.DynamicOptions, dynamicSvc dynamic.IDynamic) error
  • func (k *Kafka) Name() string
  • func (k *Kafka) NewLag(readArgs *args.KafkaReadArgs) (*Lag, error)
  • func (k *Kafka) Read(ctx context.Context, readOpts *opts.ReadOptions, ...) error
  • func (k *Kafka) Relay(ctx context.Context, relayOpts *opts.RelayOptions, relayCh chan interface{}, ...) error
  • func (k *Kafka) Test(_ context.Context) error
  • func (k *Kafka) Write(ctx context.Context, writeOpts *opts.WriteOptions, ...) error
• type Lag
  • func (l *Lag) GetAllPartitionsLastOffset(topic string, partitions []skafka.Partition) (int64, error)
  • func (l *Lag) GetPartitionLastOffset(topic string, part int) (int64, error)
  • func (l *Lag) Lag(ctx context.Context, resultsCh chan *records.ReadRecord, ...) error
• type Reader
• type Writer

Constants

const (
	BackendName = "kafka"

	DefaultBatchSize = 1
)

const (
	DefaultLagInterval = 5 * time.Second
)

const (
	RetryReadInterval = 5 * time.Second
)

const (
	RetrySampledReadInterval = 10 * time.Second
)

Variables

var (
	ErrMissingTopic = errors.New("You must specify at least one topic")
)

Functions

func ConnectAllTopics

func ConnectAllTopics(dialer *skafka.Dialer, connArgs *args.KafkaConn, topics []string) (map[string]*skafka.Conn, error)

func NewReaderForRead

func NewReaderForRead(dialer *skafka.Dialer, connArgs *args.KafkaConn, readArgs *args.KafkaReadArgs) (*skafka.Reader, error)

func NewReaderForRelay

func NewReaderForRelay(dialer *skafka.Dialer, connArgs *args.KafkaConn, relayArgs *args.KafkaRelayArgs) (*skafka.Reader, error)

func NewWriter

func NewWriter(dialer *skafka.Dialer, connArgs *args.KafkaConn, topics ...string) (*skafka.Writer, error)

NewWriter creates a new instance of a writer that can write messages to a topic. NOTE: Continuing to use the deprecated NewWriter() func to avoid dealing with TLS issues (since *Writer does not have a Dialer and Transport has TLS defined separate from the dialer).

Types

type Kafka

type Kafka struct {
	// contains filtered or unexported fields
}

Kafka holds all attributes required for performing a write to Kafka. This struct should be instantiated via the kafka.Read(..) func.

func New

func New(connOpts *opts.ConnectionOptions) (*Kafka, error)

func (*Kafka) Close

func (k *Kafka) Close(_ context.Context) error

Close is a noop for kafka because read/write/lag/etc. all handle conn setup and teardown on their own.

func (*Kafka) DisplayError

func (k *Kafka) DisplayError(msg *records.ErrorRecord) error

func (*Kafka) DisplayMessage

func (k *Kafka) DisplayMessage(cliOpts *opts.CLIOptions, msg *records.ReadRecord) error

func (*Kafka) Dynamic

func (k *Kafka) Dynamic(ctx context.Context, opts *opts.DynamicOptions, dynamicSvc dynamic.IDynamic) error

Dynamic starts up a new GRPC client connected to the dProxy service and receives a stream of outbound replay messages which are then written to the message bus.

func (*Kafka) Name

func (k *Kafka) Name() string

func (*Kafka) NewLag

func (k *Kafka) NewLag(readArgs *args.KafkaReadArgs) (*Lag, error)

NewLag creates a lag instance but does not perform any lag operations

func (*Kafka) Read

func (k *Kafka) Read(
	ctx context.Context,
	readOpts *opts.ReadOptions,
	resultsChan chan *records.ReadRecord,
	errorChan chan *records.ErrorRecord,
) error

func (*Kafka) Relay

func (k *Kafka) Relay(ctx context.Context, relayOpts *opts.RelayOptions, relayCh chan interface{}, errorCh chan *records.ErrorRecord) error

Relay sets up a new Kafka relayer

func (*Kafka) Test

func (k *Kafka) Test(_ context.Context) error

func (*Kafka) Write

func (k *Kafka) Write(ctx context.Context, writeOpts *opts.WriteOptions, errorCh chan *records.ErrorRecord, messages ...*records.WriteRecord) error

Write is the entry point function for performing write operations in Kafka.

This is where we verify that the passed args and flags combo makes sense, attempt to establish a connection, parse protobuf before finally attempting to perform the write.

type Lag

type Lag struct {
	// contains filtered or unexported fields
}

func (*Lag) GetAllPartitionsLastOffset

func (l *Lag) GetAllPartitionsLastOffset(topic string, partitions []skafka.Partition) (int64, error)

GetAllPartitionsLastOffset finds the MAX lastOffset across given partitions and topic.

func (*Lag) GetPartitionLastOffset

func (l *Lag) GetPartitionLastOffset(topic string, part int) (int64, error)

GetPartitionLastOffset - gets the last offset for a given partition. It is used by both Read() and Lag() to display offset stats and/or calculate lag.

func (*Lag) Lag

func (l *Lag) Lag(
	ctx context.Context,
	resultsCh chan *records.ReadRecord,
	errorCh chan *records.ErrorRecord,
	interval time.Duration,
) error

Lag fetches topic stats on the given interval and returns them over the resultsChan. This is a blocking call.

type Reader

type Reader struct {
	Conn   *skafka.Conn
	Reader *skafka.Reader
}

type Writer

type Writer struct {
	Writer *skafka.Writer
}