wal2json

pig repo add pgdg -u    # add pgdg repo and update cache

pig install wal2json;		# install via package name, for the active PG version

pig install wal2json -v 18;   # install for PG 18
pig install wal2json -v 17;   # install for PG 17
pig install wal2json -v 16;   # install for PG 16
pig install wal2json -v 15;   # install for PG 15
pig install wal2json -v 14;   # install for PG 14

wal_level = logical
max_replication_slots = 10
max_wal_senders = 10

# Create a replication slot
pg_recvlogical -d postgres --slot test_slot --create-slot -P wal2json

# Start consuming changes
pg_recvlogical -d postgres --slot test_slot --start -o pretty-print=1 -f -

# Drop the slot when done
pg_recvlogical -d postgres --slot test_slot --drop-slot

-- Create a logical replication slot
SELECT * FROM pg_create_logical_replication_slot('test_slot', 'wal2json');

-- Peek at changes (does not consume)
SELECT data FROM pg_logical_slot_peek_changes('test_slot', NULL, NULL);

-- Get and consume changes
SELECT data FROM pg_logical_slot_get_changes('test_slot', NULL, NULL,
    'pretty-print', '1');

-- Drop the slot
SELECT pg_drop_replication_slot('test_slot');

{
  "change": [
    {
      "kind": "insert",
      "schema": "public",
      "table": "my_table",
      "columnnames": ["a", "b"],
      "columntypes": ["integer", "text"],
      "columnvalues": [1, "hello"]
    },
    {
      "kind": "delete",
      "schema": "public",
      "table": "my_table",
      "oldkeys": {
        "keynames": ["a"],
        "keytypes": ["integer"],
        "keyvalues": [1]
      }
    }
  ]
}