subprocess.popen and psql

I have Django application which needs to call psql. I do this in a celery thread which looks like this:

@task()
def insert_sqldump_threaded(username, database, file):
  host = database.server.db_address

  work = subprocess.Popen([settings.PSQL, 
                          "-f%s" % file, 
                          "-d%s" % database.db_name,
                          "-h%s" % host,
                          "-U%s" % settings.DB_ADMIN_USER
                          ], env = {'PGPASSFILE': settings.DB_PASSFILE}
                          )
  work.wait()
  return work.returncode

On my development server the PGPASSFILE looks like this:

localhost:5432:*:postgres:postgres

which should be fine.

The problem is that all I get when this function gets called is an error from psql:

psql: could not translate host name "localhost" to address: Unknown server error

And now it gets really 开发者_如何学Pythonstrange, but when I don't submit the "env" variable, psql seems to recognize the host. At least then it asks for a password.

Any ideas on how to solve this?

I think postgresql needs other environment variables that you clear when you pass env. You can simply change os.environ or make a copy of it beforehand as in the following code:

import os
@task()
def insert_sqldump_threaded(username, database, file):
  d = dict(os.environ)
  d['PGPASSFILE'] = settings.DB_PASSFILE
  host = database.server.db_address

  work = subprocess.Popen([settings.PSQL, 
                          "-f%s" % file, 
                          "-d%s" % database.db_name,
                          "-h%s" % host,
                          "-U%s" % settings.DB_ADMIN_USER
                          ], env = d
                          )
  work.wait()
  return work.returncode

When you don't submit env, it picks up the environment variables from the shell you're running in - see os.environ. It must be depending on one of those for looking up localhost. You'll need to include that in the dictionary. Or just copy in everything from os.environ.