Package com.babelqueue

Class Redrive

java.lang.Object

com.babelqueue.Redrive

public final class Redrive
extends Object

DLQ redrive tooling — safe replay off the dead-letter queue (ADR-0026).

The operator-side counterpart to the runtime's dead-letter routing: it reads dead-lettered messages off a DLQ and re-publishes each to its source queue (its dead_letter .original_queue) or to a chosen queue, reset for reprocessing — the dead_letter block removed and attempts reset to 0, while job, trace_id, data and meta are preserved verbatim.

The Java core is codec-only (transports are separate artifacts), so redrive(com.babelqueue.Redrive.Transport, java.lang.String, com.babelqueue.Redrive.Options) works over a minimal Redrive.Transport the caller implements over their broker — the same shape as the otel module's Sender. The wire envelope stays frozen (GR-1) and no dependency is added.

Safety is dryRun + sandbox routing (toQueue) + select. The bypass option stamps a bq-replay-bypass transport header (see Replay) so a handler can skip external side-effects on a replay; it takes effect on transports that implement Redrive.HeaderPublisher (ADR-0027).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	Redrive.HeaderPublisher	An optional Redrive.Transport capability: publish a body together with out-of-band transport headers (e.g.
static final record	Redrive.Item	What happened to one message during a redrive(com.babelqueue.Redrive.Transport, java.lang.String, com.babelqueue.Redrive.Options) run.
static final record	Redrive.Options	Options for a redrive(com.babelqueue.Redrive.Transport, java.lang.String, com.babelqueue.Redrive.Options) run; immutable, built with the fluent withers from Redrive.Options.all().
static final record	Redrive.Reserved	A reserved DLQ message: its raw body, a transport-specific handle used to ack it, and any out-of-band transport headers (e.g.
static final record	Redrive.Result	Summary of a redrive(com.babelqueue.Redrive.Transport, java.lang.String, com.babelqueue.Redrive.Options) run.
static interface	Redrive.Transport	The minimal transport surface redrive(com.babelqueue.Redrive.Transport, java.lang.String, com.babelqueue.Redrive.Options) needs, implemented over any broker.

Method Summary

Modifier and Type	Method	Description
static Redrive.Result	redrive(Redrive.Transport transport, String dlq, Redrive.Options opts)	Drains dead-lettered messages off dlq and re-publishes each (reset) to its source queue or opts.toQueue.
static Envelope	reset(Envelope env)	Returns a copy of env reset for reprocessing: the dead_letter block is removed and attempts reset to 0; job, trace_id, data and meta are preserved verbatim.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

reset

public static Envelope reset(Envelope env)

Returns a copy of env reset for reprocessing: the dead_letter block is removed and attempts reset to 0; job, trace_id, data and meta are preserved verbatim.

redrive

public static Redrive.Result redrive(Redrive.Transport transport,
 String dlq,
 Redrive.Options opts)
                              throws Exception

Drains dead-lettered messages off dlq and re-publishes each (reset) to its source queue or opts.toQueue. Messages are drained first and then processed, so restored messages (skipped, dry-run, or undecodable) are not re-encountered; a DLQ message is acknowledged only after a successful re-publish, and an undecodable body is restored rather than dropped.

Returns:

a Redrive.Result with redriven/skipped counts and a per-message breakdown

Throws:

Exception - if the transport fails; on a publish failure the message is restored to the DLQ before the error is re-thrown