1261e93ef2
* fix: use keyed fields in struct literals - Replace unsafe reflect.StringHeader/SliceHeader with safe unsafe.String/Slice (weed/query/sqltypes/unsafe.go) - Add field names to Type_ScalarType struct literals (weed/mq/schema/schema_builder.go) - Add Duration field name to FlexibleDuration struct literals across test files - Add field names to bson.D struct literals (weed/filer/mongodb/mongodb_store_kv.go) Fixes go vet warnings about unkeyed struct literals. * fix: remove unreachable code - Remove unreachable return statements after infinite for loops - Remove unreachable code after if/else blocks where all paths return - Simplify recursive logic by removing unnecessary for loop (inode_to_path.go) - Fix Type_ScalarType literal to use enum value directly (schema_builder.go) - Call onCompletionFn on stream error (subscribe_session.go) Files fixed: - weed/query/sqltypes/unsafe.go - weed/mq/schema/schema_builder.go - weed/mq/client/sub_client/connect_to_sub_coordinator.go - weed/filer/redis3/ItemList.go - weed/mq/client/agent_client/subscribe_session.go - weed/mq/broker/broker_grpc_pub_balancer.go - weed/mount/inode_to_path.go - weed/util/skiplist/name_list.go * fix: avoid copying lock values in protobuf messages - Use proto.Merge() instead of direct assignment to avoid copying sync.Mutex in S3ApiConfiguration (iamapi_server.go) - Add explicit comments noting that channel-received values are already copies before taking addresses (volume_grpc_client_to_master.go) The protobuf messages contain sync.Mutex fields from the message state, which should not be copied. Using proto.Merge() properly merges messages without copying the embedded mutex. * fix: correct byte array size for uint32 bit shift operations The generateAccountId() function only needs 4 bytes to create a uint32 value. Changed from allocating 8 bytes to 4 bytes to match the actual usage. This fixes go vet warning about shifting 8-bit values (bytes) by more than 8 bits. * fix: ensure context cancellation on all error paths In broker_client_subscribe.go, ensure subscriberCancel() is called on all error return paths: - When stream creation fails - When partition assignment fails - When sending initialization message fails This prevents context leaks when an error occurs during subscriber creation. * fix: ensure subscriberCancel called for CreateFreshSubscriber stream.Send error Ensure subscriberCancel() is called when stream.Send fails in CreateFreshSubscriber. * ci: add go vet step to prevent future lint regressions - Add go vet step to GitHub Actions workflow - Filter known protobuf lock warnings (MessageState sync.Mutex) These are expected in generated protobuf code and are safe - Prevents accumulation of go vet errors in future PRs - Step runs before build to catch issues early * fix: resolve remaining syntax and logic errors in vet fixes - Fixed syntax errors in filer_sync.go caused by missing closing braces - Added missing closing brace for if block and function - Synchronized fixes to match previous commits on branch * fix: add missing return statements to daemon functions - Add 'return false' after infinite loops in filer_backup.go and filer_meta_backup.go - Satisfies declared bool return type signatures - Maintains consistency with other daemon functions (runMaster, runFilerSynchronize, runWorker) - While unreachable, explicitly declares the return satisfies function signature contract * fix: add nil check for onCompletionFn in SubscribeMessageRecord - Check if onCompletionFn is not nil before calling it - Prevents potential panic if nil function is passed - Matches pattern used in other callback functions * docs: clarify unreachable return statements in daemon functions - Add comments documenting that return statements satisfy function signature - Explains that these returns follow infinite loops and are unreachable - Improves code clarity for future maintainers
SeaweedMQ Message Queue on SeaweedFS (WIP, not ready)
What are the use cases it is designed for?
Message queues are like water pipes. Messages flow in the pipes to their destinations.
However, what if a flood comes? Of course, you can increase the number of partitions, add more brokers, restart, and watch the traffic level closely.
Sometimes the flood is expected. For example, backfill some old data in batch, and switch to online messages. You may want to ensure enough brokers to handle the data and reduce them later to cut cost.
SeaweedMQ is designed for use cases that need to:
- Receive and save large number of messages.
- Handle spike traffic automatically.
What is special about SeaweedMQ?
- Separate computation and storage nodes to scale independently.
- Unlimited storage space by adding volume servers.
- Unlimited message brokers to handle incoming messages.
- Offline messages can be operated as normal files.
- Scale up and down with auto split and merge message topics.
- Topics can automatically split into segments when traffic increases, and vice verse.
- Pass messages by reference instead of copying.
- Clients can optionally upload the messages first and just submit the references.
- Drastically reduce the broker load.
- Stateless brokers
- All brokers are equal. One broker is dynamically picked as the leader.
- Add brokers at any time.
- Allow rolling restart brokers or remove brokers at a pace.
Design
How it works?
Brokers are just computation nodes without storage. When a broker starts, it reports itself to masters. Among all the brokers, one of them will be selected as the leader by the masters.
A topic needs to define its partition key on its messages.
Messages for a topic are divided into segments. One segment can cover a range of partitions. A segment can be split into 2 segments, or 2 neighboring segments can be merged back to one segment.
During write time, the client will ask the broker leader for a few brokers to process the segment.
The broker leader will check whether the segment already has assigned the brokers. If not, select a few brokers based on their loads, save the selection into filer, and tell the client.
The client will write the messages for this segment to the selected brokers.
Failover
The broker leader does not contain any state. If it fails, the masters will select a different broker.
For a segment, if any one of the selected brokers is down, the remaining brokers should try to write received messages to the filer, and close the segment to the clients.
Then the clients should start a new segment. The masters should assign other healthy brokers to handle the new segment.
So any brokers can go down without losing data.
Auto Split or Merge
(The idea is learned from Pravega.)
The brokers should report its traffic load to the broker leader periodically.
If any segment has too much load, the broker leader will ask the brokers to tell the client to close current one and create two new segments.
If 2 neighboring segments have the combined load below average load per segment, the broker leader will ask the brokers to tell the client to close this 2 segments and create a new segment.