* feat: add S3 bucket size and object count metrics
Adds periodic collection of bucket size metrics:
- SeaweedFS_s3_bucket_size_bytes: logical size (deduplicated across replicas)
- SeaweedFS_s3_bucket_physical_size_bytes: physical size (including replicas)
- SeaweedFS_s3_bucket_object_count: object count (deduplicated)
Collection runs every 1 minute via background goroutine that queries
filer Statistics RPC for each bucket's collection.
Also adds Grafana dashboard panels for:
- S3 Bucket Size (logical vs physical)
- S3 Bucket Object Count
* address PR comments: fix bucket size metrics collection
1. Fix collectCollectionInfoFromMaster to use master VolumeList API
- Now properly queries master for topology info
- Uses WithMasterClient to get volume list from master
- Correctly calculates logical vs physical size based on replication
2. Return error when filerClient is nil to trigger fallback
- Changed from 'return nil, nil' to 'return nil, error'
- Ensures fallback to filer stats is properly triggered
3. Implement pagination in listBucketNames
- Added listBucketPageSize constant (1000)
- Uses StartFromFileName for pagination
- Continues fetching until fewer entries than limit returned
4. Handle NewReplicaPlacementFromByte error and prevent division by zero
- Check error return from NewReplicaPlacementFromByte
- Default to 1 copy if error occurs
- Add explicit check for copyCount == 0
* simplify bucket size metrics: remove filer fallback, align with quota enforcement
- Remove fallback to filer Statistics RPC
- Use only master topology for collection info (same as s3.bucket.quota.enforce)
- Updated comments to clarify this runs the same collection logic as quota enforcement
- Simplified code by removing collectBucketSizeFromFilerStats
* use s3a.option.Masters directly instead of querying filer
* address PR comments: fix dashboard overlaps and improve metrics collection
Grafana dashboard fixes:
- Fix overlapping panels 55 and 59 in grafana_seaweedfs.json (moved 59 to y=30)
- Fix grid collision in k8s dashboard (moved panel 72 to y=48)
- Aggregate bucket metrics with max() by (bucket) for multi-instance S3 gateways
Go code improvements:
- Add graceful shutdown support via context cancellation
- Use ticker instead of time.Sleep for better shutdown responsiveness
- Distinguish EOF from actual errors in stream handling
* improve bucket size metrics: multi-master failover and proper error handling
- Initial delay now respects context cancellation using select with time.After
- Use WithOneOfGrpcMasterClients for multi-master failover instead of hardcoding Masters[0]
- Properly propagate stream errors instead of just logging them (EOF vs real errors)
* improve bucket size metrics: distributed lock and volume ID deduplication
- Add distributed lock (LiveLock) so only one S3 instance collects metrics at a time
- Add IsLocked() method to LiveLock for checking lock status
- Fix deduplication: use volume ID tracking instead of dividing by copyCount
- Previous approach gave wrong results if replicas were missing
- Now tracks seen volume IDs and counts each volume only once
- Physical size still includes all replicas for accurate disk usage reporting
* rename lock to s3.leader
* simplify: remove StartBucketSizeMetricsCollection wrapper function
* fix data race: use atomic operations for LiveLock.isLocked field
- Change isLocked from bool to int32
- Use atomic.LoadInt32/StoreInt32 for all reads/writes
- Sync shared isLocked field in StartLongLivedLock goroutine
* add nil check for topology info to prevent panic
* fix bucket metrics: use Ticker for consistent intervals, fix pagination logic
- Use time.Ticker instead of time.After for consistent interval execution
- Fix pagination: count all entries (not just directories) for proper termination
- Update lastFileName for all entries to prevent pagination issues
* address PR comments: remove redundant atomic store, propagate context
- Remove redundant atomic.StoreInt32 in StartLongLivedLock (AttemptToLock already sets it)
- Propagate context through metrics collection for proper cancellation on shutdown
- collectAndUpdateBucketSizeMetrics now accepts ctx
- collectCollectionInfoFromMaster uses ctx for VolumeList RPC
- listBucketNames uses ctx for ListEntries RPC
f5c666052e