Ring:mapping Streaming Events

Streaming Event Mapping (lib-streaming, PM-team)

When to use

• User requests an event catalog, eventable-point inventory, or "where should we emit events" map
• PM team prepares a Lerian Go service for client-facing event streaming subscriptions
• Pre-flight to ring:instrumenting-streaming-events
• Task mentions "event mapping", "streaming inventory", "eventable points", "client event subscription"

Skip when

• Service is not a Go project (lib-streaming is Go-only)
• Service has no business logic to emit events about (pure infrastructure, gateway, sidecar, proxy)
• Task is purely documentation, configuration, or non-discovery
• Service is consumer-only with no outbound business event surface

Sequence

Runs before: ring:instrumenting-streaming-events

Related

Complementary: ring:instrumenting-streaming-events, ring:codebase-explorer, ring:mapping-feature-relationships

Prerequisites

• Go service codebase available for read access
• At least one entry point present (HTTP route, gRPC method, RabbitMQ consumer, scheduled job, webhook)
• Tenant identity resolvable from request context

Orchestrates 3-pass codebase discovery to produce an event catalog and instrumentation map for lib-streaming. You orchestrate. Agents explore. You NEVER read, write, or edit source code directly.

Announce at start: "Using ring:mapping-streaming-events through 7 gates (0-7)."

Streaming Architecture

lib-streaming is a producer-only, write-only event-emission library for Lerian Go services. Events are emitted via emitter.Emit(ctx, EmitRequest{DefinitionKey, TenantID, Subject, Payload}) against the streaming.Emitter interface (constructed via streaming.NewBuilder().Catalog(...).Build(ctx)). Wire format: CloudEvents 1.0 binary mode. Each RouteDefinition selects a transport — Kafka, SQS, RabbitMQ, EventBridge, or Custom. Per-tenant SaaS subscription remains the primary delivery model regardless of transport; Kafka topic naming is lerian.streaming.<resource>.<event>[.vN] with tenant carried on the ce-tenantid CloudEvents header.

WebFetch canonical docs: https://raw.githubusercontent.com/LerianStudio/lib-streaming/main/doc.go WebFetch agent constraints: https://raw.githubusercontent.com/LerianStudio/lib-streaming/main/AGENTS.md WebFetch changelog: https://raw.githubusercontent.com/LerianStudio/lib-streaming/main/CHANGELOG.md

Scope Fence

A candidate is a streamable business fact if and ONLY if ALL of:

1. Past-tense — something that already happened (account.created, not account.create)
2. Durable — the underlying state is persisted
3. Broadcastable — multiple consumers could legitimately receive it
4. Tenant-scoped — the event belongs to a tenant (or marked SystemEvent with explicit justification)

Candidates failing ANY of the four → REJECT with documented reason.

Delivery Postures

Gate Overview

Gates execute sequentially. Pass 3 (Gate 3) parallelizes internally per segment.

Gate 0: Stack Detection

Orchestrator executes directly. Detect in parallel:

1. Go version:          grep "^go " go.mod | head -1
2. lib-streaming:       grep "lib-streaming" go.mod
3. HTTP framework:      grep -rn "gofiber/fiber\|labstack/echo\|gin-gonic" internal/ go.mod
4. gRPC server:         grep -rn "grpc.NewServer" internal/
5. RabbitMQ command consumers:  grep -rn "lib-commons/v5/commons/rabbitmq" internal/   # command-queue plumbing; eventable publish sites should migrate to lib-streaming
6. Scheduled jobs:      grep -rn "robfig/cron\|time.NewTicker" internal/
7. Webhook receivers:   grep -rn "webhook\|/hooks/" internal/
8. Worker patterns:     grep -rn "commons.Launcher\|commons.App" internal/
9. Tenant source:       grep -rn "tmcore.GetTenantIDContext\|GetTenantID" internal/
10. DDD layout:         ls internal/services/ internal/domain/ 2>/dev/null
11. Database:           grep -rn "jackc/pgx\|database/sql" go.mod

HARD GATE: If not Go → STOP. If tenant source undetectable → STOP and ask user.

Gate 1: Pass 1 — Survey

Dispatch ring:codebase-explorer to produce docs/streaming/_pass1-survey.md with:

• Service Identity (name, purpose, bounded context)
• Entry Point Inventory (HTTP routes, gRPC methods, RabbitMQ consumers, cron jobs, webhooks, CLIs)
• Aggregate Inventory (name, persistence, lifecycle states)
• Tenant Identity Resolution (idiomatic call, where set, reliability per entry type)
• External Dependencies (databases, APIs, brokers)
• Notes for Pass 2

Include in dispatch: stack detection results, lib-streaming WebFetch URLs, constraint to NOT propose events.

Verification: File exists, all 6 sections present, ≥1 entry point, ≥1 aggregate, tenant source identified.

Gate 2: Pass 2 — Slice + Scope Fence

Dispatch ring:codebase-explorer with Pass 1 output to produce docs/streaming/_pass2-segments.md with:

• Segmentation Strategy (by domain module, aggregate, or entry-point type)
• Segments (3-8): files glob, aggregates touched, commit boundaries, pre/post-fence candidate counts
• Scope Fence Application table (file:line, candidate, 4-test scoring, verdict)
• Pass 3 Dispatch Plan (segments with accepted candidates + sub-prompt hints)

Verification: File exists, ≥1 segment, fence table covers all candidates, ≥1 accepted candidate.

HARD GATE: If post-fence count = 0 across all segments → STOP and surface to user.

Gate 3: Pass 3 — Mark (Parallel)

⛔ STOP-CHECK BEFORE DISPATCH

Before emitting any Task call, count the explorers you intend to launch in this turn.

• Count MUST equal the number of segments identified in Gate 2.
• If your dispatch count diverges from the Gate 2 segment count → STOP and reconcile.
• One explorer per segment. No substitutions, no omissions.

⛔ MUST NOT trickle-dispatch

All segment explorers leave in the SAME TURN, before reading any explorer output.

Forbidden sequences:

• Dispatch segment 1 → read result → dispatch segment 2
• Dispatch a subset → wait → dispatch the rest
• Dispatch follow-up explorers conditioned on partial output
• Loop sequentially over the segment list

If you find yourself about to dispatch an explorer in a turn AFTER any explorer has already returned a result → STOP. You violated parallel dispatch. Report the violation and mark the gate INCOMPLETE rather than completing the trickle.

Self-verify after dispatch

After the dispatch turn, verify all segment Task calls were emitted in that single turn. If fewer went out than the Gate 2 segment count, the gate did NOT execute correctly. Mark INCOMPLETE and surface the dispatch failure — do NOT silently continue with a partial pool.

Parallel dispatch — atomic batch

Emit all scoped Task calls (the count established in the STOP-CHECK above) in a SINGLE TURN, as one atomic batch.

If your runtime exposes a multi_tool_use.parallel wrapper, use it to dispatch the complete pool in one wrapped invocation. This is the canonical fan-out mechanism on OpenAI-style tool envelopes and on certain Anthropic SDK consumers — naming it explicitly activates parallel emission on runtimes where trickle-dispatch is the default behavior.

If your runtime emits parallel tool_use blocks natively (Claude Code with Claude models), multi_tool_use.parallel may not be needed — but naming it is harmless and serves as an enforcement anchor.

The STOP-CHECK, anti-trickle, and self-verify guards above remain binding regardless of which mechanism your runtime uses.

For EACH segment from Gate 2, dispatch ring:codebase-explorer IN PARALLEL. Each outputs docs/streaming/_pass3-{segment_name}.json.

Per-segment JSON shape:

{
  "segment": "{segment_name}",
  "events": [{
    "definition_key": "transaction.posted",
    "resource_type": "transaction",
    "event_type": "posted",
    "schema_version": "1.0.0",
    "data_content_type": "application/json",
    "data_schema": "",
    "is_system_event": false,
    "description": "...",
    "instrumentation_sites": [{"file": "...", "line_anchor": "...", "emission_timing": "post-commit", "current_function": "..."}],
    "payload_sketch": {"field_name": "type"},
    "tenant_source_at_site": "tmcore.GetTenantIDContext(ctx)",
    "consumer_idempotency_key_candidate": "event_id",
    "posture": "CRITICAL",
    "posture_rationale": "...",
    "delivery_policy": {"enabled": true, "direct": "skip", "outbox": "always", "dlq": "on_routable_failure"}
  }]
}

Include in every dispatch: lib-streaming WebFetch URLs, scope fence rules, posture decision tree, naming convention (<resource>.<event> lowercase dotted).

Verification: One JSON file per segment, valid JSON, all required fields populated, no null/TBD, CUSTOM posture has ≥80 char rationale.

HARD GATE: Missing/malformed file → re-dispatch ONLY failing segments.

Gate 4: Catalog Assembly + Validation

Orchestrator merges all _pass3-*.json events into docs/streaming/instrumentation-map.json. Validate:

• definition_key unique, matches ^[a-z][a-z0-9_]*\.[a-z][a-z0-9_]*$
• (resource_type, event_type, schema_version) triple unique
• Non-system events have tenant_source_at_site non-empty
• description ≥40 chars, payload_sketch ≥1 field
• Delivery policy matches canonical posture mapping for non-CUSTOM
• CUSTOM has posture_rationale ≥80 chars
• delivery_policy.enabled present and boolean (typically true); direct ∈ {"direct","skip"}, outbox ∈ {"never","fallback_on_circuit_open","always"}, dlq ∈ {"never","on_routable_failure"} — these are the lib-streaming mode strings the dev skill will emit verbatim

Validation failures → re-dispatch failing segment's Pass 3 with correction notes. Do NOT manually edit JSON.

Gate 5: Business Rendering

Orchestrator generates docs/streaming/event-catalog.md from validated JSON. Required sections:

• Overview (service summary, catalog stats, posture distribution)
• Scope Fence (excluded types table)
• Event Catalog (grouped by posture: CRITICAL, IMPORTANT, OBSERVATIONAL, CUSTOM)
• Detailed Event Specs (one section per event with payload sketch, instrumentation sites, delivery policy)
• Next Step (PM validation instructions)

Gate 6: PM Team Validation — NEVER SKIPPABLE

Present checklist to PM team:

• All expected events present
• No unexpected events
• Posture per event correct
• Payload sketches contain right fields
• Catalog keys match desired naming convention
• PII fields correctly annotated
• CUSTOM rationales are sound

Response options:

• APPROVED → proceed to Gate 7
• REVISE: <segment>: <change> → loops back to Pass 3 for that segment
• REVISE: posture <key>: <new posture> → single-event posture change
• REVISE: scope-fence: <change> → re-runs Pass 2 + Pass 3

HARD GATE: Must not proceed to Gate 7 without explicit APPROVED.

Gate 7: Handoff Package

Produce docs/streaming/handoff-to-skill2.md summarizing:

• PM validation date
• Inputs ready for Skill #2 (instrumentation-map.json, event-catalog.md)
• Catalog summary (service, event counts by posture)
• Outbox required flag
• Next command: Skill: ring:instrumenting-streaming-events

State Persistence

Save to docs/streaming/_state.json:

{
  "skill": "mapping-streaming-events",
  "service_name": "<from Gate 0>",
  "current_gate": 0,
  "gates": {"0": "PENDING", "1": "PENDING", "2": "PENDING", "3": "PENDING", "4": "PENDING", "5": "PENDING", "6": "PENDING_USER_APPROVAL", "7": "PENDING"},
  "metrics": {"entry_points_inventoried": 0, "segments_identified": 0, "candidates_pre_scope_fence": 0, "events_after_scope_fence": 0, "events_critical": 0, "events_important": 0, "events_observational": 0, "events_custom": 0}
}