ING-704: Added initial support for DCP.

[brett19]

No description provided.

[Copilot]

Pull request overview

This PR introduces initial support for Database Change Protocol (DCP) in the codebase, enabling applications to stream database mutations and events in real-time. DCP allows clients to subscribe to data changes at the vbucket level and receive notifications about mutations, deletions, and other database events.

Key changes:

• Added DCP configuration options and event handlers throughout the client architecture
• Implemented DCP stream management with DcpStreamSet for opening/closing vbucket streams
• Created router abstractions (static and dynamic) for handling DCP events

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
multikvendpointclientmanager.go	Added DCP options and handlers to manager configuration
mock_kvclient_test.go	Generated mock implementations for new DCP client methods
kvendpointclientmanager.go	Threaded DCP options through endpoint client manager
kvclientpool.go	Updated client pool to propagate DCP configuration
kvclientbabysitter.go	Added DCP options to client babysitter initialization
kvclient_ops.go	Implemented DCP stream request and close stream operations
kvclient_dcp.go	Core DCP bootstrapping logic with feature negotiation
kvclient.go	Integrated DCP state management and unsolicited packet handling
dcpstreamset.go	Manages multiple DCP streams across vbuckets
dcpstreamrouter_static.go	Static router for dispatching DCP events to handlers
dcpstreamrouter_dyn.go	Dynamic router with stream registration/unregistration
dcpevents.go	Defined DCP event handler types
dcpcomponent.go	Stream set manager for creating DCP stream sets
agent_ops.go	Agent-level API for creating DCP stream sets
agent_dcp_int_test.go	Integration test verifying basic DCP functionality
agent.go	Initialized DCP component in agent structure

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[Copilot]

The StreamIdsEnabled field is hardcoded to false, but DCP options include an EnableStreamIds setting. Consider using c.dcpState.streamIdsEnabled or a similar mechanism to dynamically set this value based on the negotiated DCP state, ensuring consistency between the client's DCP configuration and its operational behavior.

Suggested change

	StreamIdsEnabled: false,
	StreamIdsEnabled: c.dcpState.streamIdsEnabled,

[Copilot]

Potential nil pointer dereference if state.Load() returns nil. This can happen when getHandlers is called before any streams are registered and rebuildStateLocked has not been invoked. Add a nil check for state before accessing state.streams.

Suggested change

	state := r.state.Load()
	state := r.state.Load()
	if state == nil {
	return DcpEventsHandlers{}, false
	}