[pg-query-stream] connection type parsers not applied to streamed rows

[aravindanve]

The type overrides configured at the pool or client level are not applied to the rows returned by the stream. However it works if type overrides are explicitly passed to the QueryStream

const typeInt8 = 20;
const types = new TypeOverrides();

types.setTypeParser(typeInt8, value => 'test');

const pool = new pg.Pool({ types });

pool.connect((err, client, release) => {
  client.query('select 1::int8 as num;', (err, result) => {
    console.log('query:', result.rows[0]);
  });

  client
    .query(new QueryStream('select 1::int8 as num;'))
    .pipe(new stream.Transform({
      objectMode: true,
      transform(chunk) {
        console.log('implicit:', chunk);
      }
    }))

  client
    .query(new QueryStream('select 1::int8 as num;', null, { types }))
    .pipe(new stream.Transform({
      objectMode: true,
      transform(chunk) {
        console.log('explicit:', chunk);
      }
    }))
});

Outputs

query: { num: 'test' }
implicit: { num: '1' }
explicit: { num: 'test' }

[aravindanve]

node-postgres/packages/pg/lib/client.js

Lines 542 to 544 in f0bf3cd

	if (query._result && !query._result._types) {
	query._result._types = this._types
	}

^___ This seems to be the problem, adding the following line to the bottom of the PgQueryStream constructor fixes the issue:

class PgQueryStream extends stream.Readable {
  constructor(text, values, config = {}) {
    ...
    this._result = this.cursor._result;
  }
  ...

Should I send a PR?

[brianc]

Thanks for pointing that out! A PR would be fabulous ❤️

…

On Thu, Jul 9, 2020 at 3:15 PM Aravindan Ve ***@***.***> wrote: https://github.com/brianc/node-postgres/blob/f0bf3cda7b05be77e84c067a231bbb9db7c96c39/packages/pg/lib/client.js#L542-L544 This seems to be the problem, adding the following line to the bottom of the PgQueryStream constructor fixes the issue: class PgQueryStream extends stream.Readable { constructor(text, values, config = {}) { ... this._result = this.cursor._result; } ... Should I send a PR? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2270 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAMHIPQC2PGTU2KGEK7F73R2YQNRANCNFSM4OV5IPRA> .

[aravindanve]

Done #2271

Also, while writing the test I noticed that rowMode is not falling back to client config as well. But the same fix did not work. It appears that the fault may be on pg client's end? I am not sure yet, but from a cursory look, it appears that pg client does not pass on rowMode configuration to the query at all.