Module stream 

Redis Stream consumer for CDC events.

Tails a peer’s cdc stream and parses events.

Stream Trimming

Redis streams can be trimmed via MAXLEN or MINID to bound memory. If our cursor points to an entry older than the oldest in the stream, we’ve “fallen behind” and missed events. This module detects this and returns a StreamTrimmed result so callers can:

• Log a warning (potential data gap)
• Reset cursor to oldest available entry
• Emit a metric for alerting

Content Hash Validation

When a PUT event includes a hash field, we verify that the SHA256 of the decompressed data matches. This detects corruption from:

• Network bit flips
• Compression bugs
• Malicious peers

Structs

CdcEvent

A parsed CDC event from the stream.

CdcMeta

Metadata from a CDC PUT event.

StreamTailer

Stream tailer for a single peer’s CDC stream.

Enums

CdcOp

CDC operation type.

ReadResult

Result of reading from a stream, accounting for trim scenarios.

Functions

calculate_lag_ms

Calculate the time lag in milliseconds between two stream IDs.

compare_stream_ids

Compare two Redis stream IDs.

maybe_decompress

Decompress zstd data if it has the magic header, otherwise return as-is.

parse_stream_id_timestamp

Parse the timestamp (milliseconds since epoch) from a stream ID.