django1/django/db/backends/postgresql/client.py

from django.db.backends import BaseDatabaseClient
from django.conf import settings
import os

class DatabaseClient(BaseDatabaseClient):
    def runshell(self):
        args = ['psql']
        if settings.DATABASE_USER:
            args += ["-U", settings.DATABASE_USER]
        if settings.DATABASE_PASSWORD:
            args += ["-W"]
        if settings.DATABASE_HOST:
            args.extend(["-h", settings.DATABASE_HOST])
        if settings.DATABASE_PORT:
            args.extend(["-p", str(settings.DATABASE_PORT)])
        args += [settings.DATABASE_NAME]
        os.execvp('psql', args)