Wire Tap

A production pipeline processes events normally, but the debugging team needs to inspect the traffic without affecting throughput. The wire-tap pattern copies each event to a side channel for inspection, logging, or analysis -- without modifying the main pipeline's behavior or adding latency.

Pipeline

[wtp_receive]
     |
     v
     +───────────────────────────────────+
     | [wtp_main_flow] | [wtp_tap_audit] |
     +───────────────────────────────────+
     [join]

Workflow inputs: message, auditLevel

The FORK_JOIN runs the main processing path and the audit tap in parallel. The main flow completes independently of the tap -- a slow or failing audit logger does not block the primary message path.

Workers

WtpReceiveWorker (task: wtp_receive)

Receives the incoming message and passes it through unchanged. Reads message from workflow input and outputs it as-is for both the main flow and the audit tap to consume.

• Writes message

WtpMainFlowWorker (task: wtp_main_flow)

Processes the message through the primary business logic path. Outputs a result map containing processed = true, action = "message_handled", and a timestamp from Instant.now().

• Writes result

WtpTapAuditWorker (task: wtp_tap_audit)

Copies the message to a side-channel audit log without affecting the main flow. Generates a unique auditLogId prefixed with "AUD-" using System.currentTimeMillis() encoded in base-36. Builds an auditEntry map with the current Instant.now() timestamp, the auditLevel from workflow input (defaults to "info"), and source = "wire_tap".

• Writes tapped, auditLogId, auditEntry

---

12 tests | Workflow: wtp_wire_tap | Timeout: 60s

See RUNNING.md for setup and usage.