Django和Postgres之间的连接错误

Question

我正在用Django建立一个亚马逊AWS测试服务器，我在上面使用Postgres作为数据库。这是我来这里的方式：

$ sudo apt update
$ sudo apt install python3-pip python3-dev libpq-dev postgresql postgresql-contrib 

我从Github下载了我的文件，并为它创建了一个虚拟环境，在里面我安装了psycopg2。

$ pip install psycopg2

我如何配置Postgres:

$ sudo -i -u postgres
$ psql
$ createuser --interactive (super user);
$ createdb Filme;

其他一些可能对Postgres有用的信息：

$ service postgresql status
> postgresql.service - PostgreSQL RDBMS
Loaded: loaded (/lib/systemd/system/postgresql.service; enabled; vendor preset:>
Active: active (exited) since Wed 2022-10-05 17:08:25 UTC; 20h ago
Main PID: 977 (code=exited, status=0/SUCCESS)
CPU: 1ms
Oct 05 17:08:25 ip-172-31-29-151 systemd[1]: Starting PostgreSQL RDBMS...
Oct 05 17:08:25 ip-172-31-29-151 systemd[1]: Finished PostgreSQL RDBMS.

$ pg_lsclusters
> Ver Cluster Port Status Owner    Data directory              Log file
14  main    5432 online postgres /var/lib/postgresql/14/main /var/log/postgresql/postgresql-14-main.log

在我的项目的settings.py文件中：

DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'Filme',
}
}

当我尝试运行迁移到新数据库时发生错误：

$ (env) $ python3 manage.py migrate
> Traceback (most recent call last):
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/base/base.py", line 282, in ensure_connection
self.connect()
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/utils/asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/base/base.py", line 263, in connect
self.connection = self.get_new_connection(conn_params)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/utils/asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/postgresql/base.py", line 215, in get_new_connection
connection = Database.connect(**conn_params)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/psycopg2/__init__.py", line 122, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
psycopg2.OperationalError: connection to server on socket "/var/run/postgresql/.s.PGSQL.5432" failed: FATAL:  role "ubuntu" does not exist

The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/home/ubuntu/Filmes/manage.py", line 22, in <module>
main()
File "/home/ubuntu/Filmes/manage.py", line 18, in main
execute_from_command_line(sys.argv)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/core/management/__init__.py", line 446, in execute_from_command_line
utility.execute()
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/core/management/__init__.py", line 440, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/core/management/base.py", line 402, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/core/management/base.py", line 448, in execute
output = self.handle(*args, **options)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/core/management/base.py", line 96, in wrapped
res = handle_func(*args, **kwargs)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/core/management/commands/migrate.py", line 114, in handle
executor = MigrationExecutor(connection, self.migration_progress_callback)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/migrations/executor.py", line 18, in __init__
self.loader = MigrationLoader(self.connection)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/migrations/loader.py", line 58, in __init__
self.build_graph()
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/migrations/loader.py", line 235, in build_graph
self.applied_migrations = recorder.applied_migrations()
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/migrations/recorder.py", line 81, in applied_migrations
if self.has_table():
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/migrations/recorder.py", line 57, in has_table
with self.connection.cursor() as cursor:
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/utils/asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/base/base.py", line 323, in cursor
return self._cursor()
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/base/base.py", line 299, in _cursor
self.ensure_connection()
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/utils/asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/base/base.py", line 281, in ensure_connection
with self.wrap_database_errors:
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/utils.py", line 91, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/base/base.py", line 282, in ensure_connection
self.connect()
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/utils/asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/base/base.py", line 263, in connect
self.connection = self.get_new_connection(conn_params)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/utils/asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/django/db/backends/postgresql/base.py", line 215, in get_new_connection
connection = Database.connect(**conn_params)
File "/home/ubuntu/Filmes/env/lib/python3.10/site-packages/psycopg2/__init__.py", line 122, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
django.db.utils.OperationalError: connection to server on socket "/var/run/postgresql/.s.PGSQL.5432" failed: FATAL:  role "ubuntu" does not exist

附言：我也遵循了DigitalOcean教程，但我最终陷入了一个几乎相同的错误。(https://www.digitalocean.com/community/tutorials/how-to-set-up-django-with-postgres-nginx-and-gunicorn-on-ubuntu-18-04)

Answer 1

您只配置了ENGINE和NAME设置。您已将所有其他数据库连接设置保留为默认设置，如用户名、密码等。因此，它正在尝试使用当前Linux用户的用户名(看起来是ubuntu(连接到数据库。我猜，当您运行createuser时，您没有指定ubuntu的用户名，也没有将密码留空，所以您需要在Django数据库配置中设置这些设置。

查看您链接的"数字海洋"教程中的所有数据库连接设置，并与您在设置文件中配置的两个设置进行比较。

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请注意，由于您只是在同一台服务器上运行Django和Postgres，因此您的问题没有任何特定于AWS的内容。这与在任何其他Linux服务器上配置Django/PostgreSQL的方式相同。如果您正在搜索"；django连接到AWS上的postgres"；或者类似的事情，(关注你问题的AWS方面，而实际上你的问题根本没有AWS方面(，这可能会阻止你找到问题的答案。