Replicant.Decoder (Replicant v1.4.0)

The decode boundary + dispatcher for the logical-replication stream.

decode/2 dispatches one XLogData payload to the configured decoder plugin (ADR-0009; opts[:decoder], default :pgoutput) and is the value-free-error boundary (Critical Rule 1): it catches every raise/throw/exit from ANY plugin's parser — the vendored pgoutput byte parser raises on malformed input, the pglogical parser throws on malformed frames, the wal2json JSON decoder errors on malformed JSON — scrubs the raw bytes, and returns a value-free {:error, %Replicant.Error{}}. No row value or raw WAL byte ever escapes the decode boundary.

The pgoutput byte parser (pgoutput_decode/2, @doc false) is vendored from walex (MIT; see NOTICE), itself derived from cainophile and supabase-realtime; it produces %Unsupported{data: binary} (carrying raw bytes) for unknown message types, which decode/2 normalises value-free. Callers MUST use decode/2.

Summary

Functions

decode(binary, opts \\ [])

Decode one replication payload through the configured decoder plugin, value-free on failure.

Functions

decode(binary, opts \\ [])

@spec decode(
  binary(),
  keyword()
) :: {:ok, [struct()], term()} | {:error, Replicant.Error.t()}

Decode one replication payload through the configured decoder plugin, value-free on failure.

opts[:decoder] selects the plugin (:pgoutput default, :pglogical, :wal2json); opts[:cache] is the plugin's per-connection state (threaded by the Connection). Returns {:ok, messages, cache} (zero or more decoded structs — wal2json emits a synthesized %Relation{} ahead of a schema-drifted change) or {:error, %Error{reason: :decode_failure | :unsupported_message | ...}} — never raises, never surfaces raw bytes.