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Feature Matrix
Current capability overview for the broker.
AMQP Protocol
| Capability | Status | Notes |
|---|---|---|
| Connection lifecycle | Implemented | Handshake + heartbeat |
| Heartbeats | Implemented | Fixed server interval |
| Channels open/close | Implemented | Proper error codes |
| Connection close | Implemented | Errors & heartbeat timeout |
| Publish messages | Implemented | direct / fanout / topic routing |
| Content headers & properties | Implemented | Preserved end-to-end |
| Large message framing | Implemented | Multi-frame up to negotiated frame_max |
| Basic consume / cancel | Implemented | Single consumer per channel; CancelOk supported |
| Ack / Nack / Reject | Implemented | multiple + requeue |
| QoS (prefetch) | Implemented | Per-channel & per-consumer (global flag) |
| Publisher confirms | Implemented | Ack after full content publish |
| Basic.get | Implemented | GetOk / GetEmpty with ack semantics |
| Transactions (tx.select/commit/rollback) | Implemented | Buffered until commit |
| Basic.recover | Implemented | Requeue all unacked deliveries |
| Exchange declare/delete | Implemented | direct / fanout / topic |
| Queue declare/delete/purge | Implemented | passive/exclusive/auto_delete + durability recovery |
| Bind / Unbind | Implemented | Active routing for declared exchanges |
Exchange Types
| Type | Status | Notes |
|---|---|---|
| direct | Implemented | Exact routing key match |
| fanout | Implemented | Broadcast to all bound queues |
| topic | Implemented | Wildcards * and # |
| headers | Implemented | Simplified any:/all: logic |
| x-delayed-message | Not Implemented | Planned |
| internal exchanges | Not Implemented | Planned |
Queues & Messages
| Capability | Status | Notes |
|---|---|---|
| Durable queues | Implemented | Segmented WAL + recovery |
| Exclusive queues | Implemented | Owned by connection |
| Auto-delete queues | Implemented | Delete after last consumer removal |
| Message persistence | Implemented | WAL + ack bitmap + recovery + quota policies |
| Partial segment compaction | Implemented | Fragment threshold + CRC + metrics |
| Message priority | Implemented | 0–255 |
| TTL (message & queue) | Implemented | Expiration + queue TTL |
| Dead-letter (DLX) | Implemented | TTL, nack/reject, overflow with x-death history |
| Max length / overflow policies | Implemented | drop-head / reject-publish / reject-publish-dlx |
| Single active consumer | Not Implemented | Planned |
| Per-consumer prefetch | Implemented | Independent windows |
| Redelivery flag | Implemented | Set on requeue |
| Headers (app properties) | Implemented | Preserved |
| Expiration property | Implemented | Per-message TTL |
Auth & Authorization
| Capability | Status | Notes |
|---|---|---|
| SASL PLAIN | Implemented | Bcrypt/Argon2 hashes |
| SASL AMQPLAIN | Implemented | LOGIN/PASSWORD table |
| SASL EXTERNAL | Implemented | TLS client cert CN + authzid |
| TLS | Implemented | Separate secure listener |
| Client cert validation | Partial | Optional client CA |
| Virtual host isolation | Implemented | Allowed vhost list |
| Regex permissions | Implemented | configure/write/read rules |
| Fine-grained policies | Not Implemented | |
| Rate limiting | Not Implemented |
Reliability & Scaling
| Capability | Status | Notes |
|---|---|---|
| Clustering | Not Implemented | Planned |
| Replication | Not Implemented | Planned |
| Federation/Shovel | Not Implemented | Planned |
| Flow control (connection.blocked) | Implemented | Memory/disk watermark alarms |
| Memory & disk alarms | Implemented | Block persistent publishes under alarm |
| Durable quota alarm | Implemented | block / reject / reject-dlx policies |
| Dead-letter strategy | Implemented | DLX + overflow |
Management & Observability
| Capability | Status | Notes |
|---|---|---|
| HTTP API | Partial | Health/info/metrics; CRUD expansion pending |
| Metrics | Implemented | Channel, publish/ack, DLX, blocked, backlog, store, compaction |
| Tracing | Planned | Standard integration hooks |
| Event firehose | Not Implemented | |
| CLI tooling | Implemented | Runtime & definitions operations |
Extensions & Integrations
| Capability | Status | Notes |
|---|---|---|
| Plugin system | Not Implemented | Planned |
| MQTT/STOMP | Not Implemented | |
| Additional protocols | Not Implemented | |
| Streams | Not Implemented | |
| Delayed message | Not Implemented |
Performance & Optimizations
| Capability | Status | Notes |
|---|---|---|
| Batch deliveries | Partial | Delivery loops batch size 500 |
| Zero-copy persistence | Not Implemented | |
| Back-pressure | Implemented | Global byte accounting + watermarks |
| frame_max negotiation | Implemented | Payload slicing |
| Heartbeat disable handling | Implemented | No busy-loop when 0 |
| Dual-port architecture | Implemented | Plain + TLS listeners |
| Fine-grained prefetch | Implemented | Channel + consumer windows |
| Consumer priority | Not Implemented |
Security
| Capability | Status | Notes |
|---|---|---|
| TLS | Implemented | Dedicated listener |
| Client cert auth | Partial | Optional CA; EXTERNAL when present |
| Password hashing | Implemented | bcrypt / argon2 |
| Runtime ACL revoke | Not Implemented | Planned |
Summary
Core messaging, durability, routing, confirmations, flow control, alarms, and metrics are implemented. Clustering, replication, advanced protocols, and plugin architecture are future roadmap items.
Legend
- Implemented: Fully available
- Partial: Basic version with room for enhancement
- Planned: On the roadmap
- Not Implemented: Not currently scheduled
Updated: 2025-11-21