The current implementation of the getFreeConnection support only one call wait.

When send multiple sql, and some sql failed, we must wait untill pqgetResult(conn.pgconn) return nil, or else, the connection will remain unusable.

.getRows(-1) works fine, but .rows() segfaults; am I using this correctly?

withConnection(dbPool, conn):
  var res = await conn.exec("select col, id from stuff limit 10")
  for row in res[0].rows():
     echo row

Traceback (most recent call last)
web.nim(18)              web
asyncdispatch.nim(1000)  runForever
asyncdispatch.nim(991)   poll
apg_core.nim(446)        cb
asyncfutures.nim(109)    complete
asyncmacro.nim(34)       cb
apg_core.nim(509)        matchIter
SIGSEGV: Illegal storage access. (Attempt to read from nil?)

line 509 is calling setLen(r[col], 0) for a little more context.

Notify can only recieve when sendNotify is send through the same connection with the notify.

proc testConnectionNotify(conn, conn2: apgConnection): Future[bool] {.async.} =
  var r1 = false
  var r2 = false
  await conn.listenNotify("testChannel")
  var notifyFuture1 = conn.notify("testChannel")
  await conn2.sendNotify("testChannel", "payload")
  #await conn.sendNotify("testChannel", "payload")
  var sleepFuture1 = sleepAsync(100)
  await notifyFuture1 or sleepFuture1
  if notifyFuture1.finished:
    echo notifyFuture1.read.payload
    r1 = true
    return true
  else:
    echo "failed"
    return false

Sorry I'm a freshman of nim-lang, I'm tring to implement a postgresql client which can listen to the notification from server, and now I'm wondering how can I get the notify message from the listenNotify proc, I'm trying to use var result = listenNotify(dbConn, "test") but with compiler error

Hi thanks for the great work.

Can we please have support for parameters in multiple statements?

There seems to be some work complete on this for https://github.com/tulayang/asyncmysql so would be good if the Postgres version also supported this.

Getting this error now:

asyncpg/apg_core.nim(528, 9) template/generic instantiation from here
apg_core.nim(503, 14) Error: type mismatch: got <nil> but expected 'string'

Pool size of 10 works, pool size of 5 does not.

import asyncdispatch, asyncpg/asyncpg

const POOL_SIZE = 5
var pool = newPool(POOL_SIZE)

proc main() {.async.} =
  var start: float
  var connStr = "host=localhost port=5432 dbname=test user="
  await pool.connect(connStr)
  var futures = newSeq[Future[apgResult]]()
  for i in 0..<10:
    futures.add exec(pool, "SELECT $1, pg_sleep(1);", i)
  var results = await all(futures)
  for res in results:
    for item in res[0].rows():
      echo item, " "

waitFor main()

Starts 10 connections that sleep for 10 seconds. If pool size is less the number of connections strange error happens:

asyncpgtest.nim(18)      asyncpgtest
asyncdispatch.nim(1654)  waitFor
asyncdispatch.nim(1514)  poll
asyncdispatch.nim(1233)  runOnce
Error: unhandled exception: No handles or timers registered in dispatcher. [ValueError]

I think if connections are not available it should error out or wait some how. I think it just forgets to register no available connection case.

Nim Compiler Version 0.19.1 [MacOSX: amd64]
Compiled at 2018-10-22
Copyright (c) 2006-2018 by Andreas Rumpf

git hash: 16c3d4332fac56b275ca3c66dcf12573738bdc91
active boot switches: -d:release

Because the listen/notify connection must be the same, and using apgPool doesn't promise it, so it is not proper when using apgPool to listen and notify, because they will get the different connection.

With this issue I would like to ask if this repo is still being actively maintained. I see there is a PR to support Nim 0.19.0 which is already quite old.