CBG-4249: Create an abstract DCPClient to be able to work with rosmar

[torcolvin]

Create an abstract DCPClient to be able to work with rosmar

I expect that this can be extended to work as a sharded or non shared DCP client as well, but I think there's interesting work here.

I made this "work" but not for attachment compaction since this uses hierarchical paths in rosmar for xattr subdoc operations https://jira.issues.couchbase.com/browse/CBG-4232

TODO

• ability to tag checkpoints with a groupID
• ability to remove checkpoint documents https://github.com/couchbaselabs/rosmar/blob/3b9ac157a3cd52c076649d31cbe385e76386787d/feeds.go#L221
• change https://github.com/couchbase/sg-bucket/blob/8c9a5acda2c223f50957df2a513a582fe7530bfd/tap.go#L82 so that sgbucket.DoneChan returns an error to avoid running another goroutine

Pre-review checklist

• Removed debug logging (fmt.Print, log.Print, ...)
• Logging sensitive data? Make sure it's tagged (e.g. base.UD(docID), base.MD(dbName))
• Updated relevant information in the API specifications (such as endpoint descriptions, schemas, ...) in docs/api

Dependencies (if applicable)

• Link upstream PRs
• Update Go module dependencies when merged

Integration Tests

• GSI=true,xattrs=true https://jenkins.sgwdev.com/job/SyncGatewayIntegration/0000/

[Copilot]

Pull Request Overview

This PR introduces an abstract DCPClient interface to support both Couchbase Server (via gocbcore) and Rosmar backends. The key change is creating a unified DCP client abstraction that dispatches to implementation-specific clients based on the underlying bucket type.

Key changes:

• Created DCPClient interface with implementations GoCBDCPClient (renamed from DCPClient) and RosmarDCPClient
• Unified DCPClientOptions struct replacing separate options for each implementation
• Removed test skips for Rosmar/Walrus, enabling DCP-based tests to run against all bucket types

Reviewed Changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
base/abstract_dcp_client.go	New abstraction layer with DCPClient interface and factory function NewDCPClient
base/rosmar_dcp_client.go	New Rosmar-specific DCP client implementation
base/dcp_client.go	Renamed DCPClient to GoCBDCPClient and DCPClientOptions to GoCBDCPClientOptions
base/dcp_client_stream_observer.go	Updated receiver types from DCPClient to GoCBDCPClient
base/gocb_dcp_feed.go	Refactored to use new client creation pattern
db/background_mgr_resync_dcp.go	Updated to use new abstract client with scope-based collection specification
db/background_mgr_attachment_migration.go	Updated to use new abstract client with scope-based collection specification
db/attachment_compaction.go	Updated to use new abstract client with scope-based collection specification
db/util_testing.go	Updated to use new abstract client with scope-based collection specification
db/background_mgr_resync_dcp_test.go	Removed Walrus test skips
db/background_mgr_attachment_migration_test.go	Removed Walrus test skips
db/attachment_compaction_test.go	Removed Walrus test skips
base/dcp_client_test.go	Removed Walrus test skips and commented out unported tests
tools/cache_perf_tool/dcpDataGeneration.go	Updated type references to GoCBDCPClient

[Copilot]

Pull request overview

Copilot reviewed 33 out of 33 changed files in this pull request and generated 9 comments.