Source Handler

The source handler receives source events and matches them against registered source targets to determine which sources to retrieve and process.

Source Events

When a source handler receives a source event, it processes the event through the following pipeline:

1. Verify the event against tenant-stored secrets
2. Match the event against registered source targets
3. For each matched source target:
   • Acquire the source target lease
   • Resolve tenant credentials
   • Retrieve the source content
   • Detect the renderer type
   • Verify the lease is still held
   • Stream the source to the renderer

Observability

The source handler sets span attributes for each source target (source-specific), tenant identity, and other event metadata. These attributes are the canonical record of what was fetched and for whom.

Replayability

In the event of a pipeline failure, the source handler can be triggered to replay a source retrieval and reinitiate the pipeline.

To reinitiate the pipeline, the source handler uses the RPC’s event ID to query the OTel collector and retrieve the information it needs to reconstruct each source target using the span attributes from the original trace.

Replay Prevention

Before replaying each source target, the source handler checks the source target lease on the source target ConfigMap:

• If a lease is currently active (held and not stale), skip — the active processing supersedes this replay.
• If the replay count for this event exceeds the configured maximum, report a permanent failure.