Module source 

MongoDB CDC source connector implementation.

Implements SourceConnector for streaming change events from MongoDB change streams into LaminarDB as Arrow RecordBatches.

Architecture

• Ring 0: No CDC code — just SPSC channel pop (~5ns)
• Ring 1: Change stream consumption, event parsing, Arrow conversion
• Ring 2: Connection management, collection validation, health checks

Cancellation Safety

The poll_batch method is cancellation-safe: dropping the future mid-execution does not lose events. Buffered events remain in the internal VecDeque and will be returned on the next poll.

Structs

MongoDbCdcSource

MongoDB CDC source connector.

Functions

mongodb_cdc_envelope_schema

Returns the Arrow schema for MongoDB CDC envelope records.