我正在运行一个 shell 脚本作为 Ubuntu 的 systemd 服务，以便在启动时启动。该脚本在内部执行一个连接到 InfluxDB（通过 Python 的 influxdb 包）的 Python 脚本 ( python_simulator.py )。
Python 脚本无法在启动时启动，检查日志表明这是因为连接到 InfluxDB 时出现“ ConnectionError ”。我将其解释为，在 Python 服务在启动时激活时，influxdb 服务可能尚未启动。因此，我尝试通过将“ After ”和“ Wants ”添加为“ influxdb.service ”来在服务中添加订单依赖项，这会在 influxdb 服务后几秒钟激活 Python 服务。但是，我仍然遇到相同的连接错误。
systemd 服务 ( myservice.service)如下所示：
[Unit]
Description= Python startup service.
After=influxdb.service
Wants=influxdb.service
[Service]
Type=forking
ExecStart=/bin/bash /home/test_user/Deploy/start.sh
ExecStop=/bin/bash /home/test_user/Deploy/stop.sh
[Install]
WantedBy=multi-user.target
Python 脚本的日志文件 ( python_simulator.py)：
Traceback (most recent call last):
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/connection.py", line 159, in _new_conn
(self._dns_host, self.port), self.timeout, **extra_kw)
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/util/connection.py", line 80, in create_connection
raise err
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/util/connection.py", line 70, in create_connection
sock.connect(sa)
ConnectionRefusedError: [Errno 111] Connection refused
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/connectionpool.py", line 600, in urlopen
chunked=chunked)
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/connectionpool.py", line 354, in _make_request
conn.request(method, url, **httplib_request_kw)
File "/usr/lib/python3.6/http/client.py", line 1239, in request
self._send_request(method, url, body, headers, encode_chunked)
File "/usr/lib/python3.6/http/client.py", line 1285, in _send_request
self.endheaders(body, encode_chunked=encode_chunked)
File "/usr/lib/python3.6/http/client.py", line 1234, in endheaders
self._send_output(message_body, encode_chunked=encode_chunked)
File "/usr/lib/python3.6/http/client.py", line 1026, in _send_output
self.send(msg)
File "/usr/lib/python3.6/http/client.py", line 964, in send
self.connect()
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/connection.py", line 181, in connect
conn = self._new_conn()
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/connection.py", line 168, in _new_conn
self, "Failed to establish a new connection: %s" % e)
urllib3.exceptions.NewConnectionError: <urllib3.connection.HTTPConnection object at 0x7f817d91b400>: Failed to establish a new connection: [Errno 111] Connection refused
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/requests/adapters.py", line 449, in send
timeout=timeout
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/connectionpool.py", line 638, in urlopen
_stacktrace=sys.exc_info()[2])
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/urllib3/util/retry.py", line 399, in increment
raise MaxRetryError(_pool, url, error or ResponseError(cause))
urllib3.exceptions.MaxRetryError: HTTPConnectionPool(host='localhost', port=8086): Max retries exceeded with url: /query?q=SHOW+DATABASES (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f817d91b400>: Failed to establish a new connection: [$
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "python_simulator.py", line 467, in <module>
main(host=args.host, port=args.port)
File "python_simulator.py", line 312, in main
for db_dict in client.get_list_database():
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/influxdb/client.py", line 570, in get_list_database
return list(self.query("SHOW DATABASES").get_points())
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/influxdb/client.py", line 416, in query
expected_response_code=expected_response_code
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/influxdb/client.py", line 267, in request
timeout=self._timeout
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/requests/sessions.py", line 533, in request
resp = self.send(prep, **send_kwargs)
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/requests/sessions.py", line 646, in send
r = adapter.send(request, **kwargs)
File "/home/test_user/Deploy/py_venv/lib/python3.6/site-packages/requests/adapters.py", line 516, in send
raise ConnectionError(e, request=request)
requests.exceptions.ConnectionError: HTTPConnectionPool(host='localhost', port=8086): Max retries exceeded with url: /query?q=SHOW+DATABASES (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f817d91b400>: Failed to establish a new connection$
最后，阻塞的守护进程树显示myservice.service在influxdb.service之后执行：
myservice.service +6.872s └─influxdb.service @11.344s └─network-online.target @11.337s └─NetworkManager-wait-online.service @4.706s +6.630s └─NetworkManager.service @3.940s +674ms └─dbus.service @3.914s └─basic.target @3.728s └─sockets.target @3.728s └─snapd.socket @3.722s +5ms └─sysinit.target @3.712s └─apparmor.service @3.276s +435ms └─local-fs.target @3.266s └─run-user-1000.mount @49.841s └─swap.target @3.160s └─dev-disk-by\x2duuid-16e1b46a\x2d79fc\x2d4965\x2d9932\x2d8f589e9e7057.swap @3.132s +23ms └─dev-disk-by\x2duuid-16e1b46a\x2d79fc\x2d4965\x2d9932\x2d8f589e9e7057.device @3.130s
我不确定为什么我仍然无法使用 influxdb 执行脚本（python_simulator.py）。还有其他依赖吗？myservice.service中是否需要任何更改？任何帮助将不胜感激。
编辑1：
原因可能是ConnectionRefusedError而不是ConnectionError，这可能是因为当它连接到端口 8086的流入时，没有任何东西在监听它？如果是这样，我怎样才能把它放在依赖顺序中？