Source & Job Orchestrator architecture

Based on Epic 9 – Source & Job Orchestrator Dashboard; this section outlines components, job lifecycle, rate-limit governance, and observability.

1) Topology

Orchestrator API (StellaOps.Orchestrator). Minimal API providing job state, throttling controls, replay endpoints, and dashboard data. Authenticated via Authority scopes (orchestrator:*).
Job ledger (Mongo). Collections jobs, job_history, sources, quotas, throttles, incidents. Append-only history ensures auditability.
Queue abstraction. Supports Mongo queue, Redis Streams, or NATS JetStream (pluggable). Each job carries lease metadata and retry policy.
Dashboard feeds. SSE/GraphQL endpoints supply Console UI with job timelines, throughput, error distributions, and rate-limit status.

Enqueue. Producer services (Concelier, Excititor, Scheduler, Export Center, Policy Engine) submit JobRequest records containing jobType, tenant, priority, payloadDigest, dependencies.
Scheduling. Orchestrator applies quotas and rate limits per {tenant, jobType}. Jobs exceeding limits are staged in pending queue with next eligible timestamp.
Leasing. Workers poll LeaseJob endpoint; Orchestrator returns job with leaseId, leaseUntil, and instrumentation tokens. Lease renewal required for long-running tasks.
Completion. Worker reports status (succeeded, failed, canceled, timed_out). On success the job is archived; on failure Orchestrator applies retry policy (exponential backoff, max attempts). Incidents escalate to Ops if thresholds exceeded.
Replay. Operators trigger POST /jobs/{id}/replay which clones job payload, sets replayOf pointer, and requeues with high priority while preserving determinism metadata.

Quotas defined per tenant/profile (maxActive, maxPerHour, burst). Stored in quotas and enforced before leasing.
Dynamic throttles allow ops to pause specific sources (pauseSource, resumeSource) or reduce concurrency.
Circuit breakers automatically pause job types when failure rate > configured threshold; incidents generated via Notify and Observability stack.

GET /api/jobs?status= — list jobs with filters (tenant, jobType, status, time window).
GET /api/jobs/{id} — job detail (payload digest, attempts, worker, lease history, metrics).
POST /api/jobs/{id}/cancel — cancel running/pending job with audit reason.
POST /api/jobs/{id}/replay — schedule replay.
POST /api/limits/throttle — apply throttle (requires elevated scope).
GET /api/dashboard/metrics — aggregated metrics for Console dashboards.

All responses include deterministic timestamps, job digests, and DSSE signature fields for offline reconciliation.

Metrics: job_queue_depth{jobType,tenant}, job_latency_seconds, job_failures_total, job_retry_total, lease_extensions_total.
Logs: structured with jobId, jobType, tenant, workerId, leaseId, status. Incident logs flagged for Ops.
Traces: spans covering enqueue, schedule, lease, worker_execute, complete. Trace IDs propagate to worker spans for end-to-end correlation.

Orchestrator exports audit bundles: jobs.jsonl, history.jsonl, throttles.jsonl, manifest.json, signatures/. Used for offline investigations and compliance.
Replay manifests contain job digests and success/failure notes for deterministic proof.

HA deployment with multiple API instances; queue storage determines redundancy strategy.
Support for maintenance mode halting leases while allowing status inspection.
Runbook includes procedures for expanding quotas, blacklisting misbehaving tenants, and recovering stuck jobs (clearing leases, applying pause/resume).