I want to be able to setup a lockstep stream off of any postgres table/view that has the few fields required by the protocol, and it will stream that table via lockstep, including any arbitrary data fields it includes.

Chunked HTTP

• A row will be returned as a JSON object:

  {
   "txid": 549163,
   "current_xmin": 551033,
   "since": 549163,
   "deleted": true,
   "data": {
     "name": "mydomain.com",
     "user_id": 1
   }
  }

Fields:

• txid: transaction at which the record was last updated (required)
• current_xmin: txid_snapshot_xmin(txid_snapshot_current()) (required)
• since: min of txid_snapshot_xmin(txid_current_snapshot()) and txid (required)
• deleted: whether or not the row is marked as deleted
• data: any data fields in the row not part of the lockstep protocol

• snapshot_completed (when the initial dump/snapshot is complete)

  {
    "control": true,
    "type": "snapshot_completed",
    "timestamp": 123456789
  }

• heartbeat (after each set of updates is sent out or when there are no rows in last n seconds)

  {
    "control": true,
    "type": "heartbeat",
    "timestamp": 123456789
  }

Tests are good. To run them, you need to have a postgres server running locally with a database named gls_test:

$ createdb gls_test

The test database URL is currently hardcoded as postgres://localhost:5432/gls_test with no authentication and no SSL. Once you have that set up, you can run the tests:

$ go test
warning: building out-of-date packages:
	gls/logger
installing these packages with 'go test -i' will speed future tests.

PASS
ok  	gls	0.119s