Python urllib3.exceptions.NewConnectionError 连接自建API答案

【问题标题】：Python urllib3.exceptions.NewConnectionError connecting to self-built APIPython urllib3.exceptions.NewConnectionError 连接自建API
【发布时间】：2021-06-23 08:16:34
【问题描述】：

我构建了一个 API（使用 flask-restful），将数据存储在其缓存中并将其公开给其他应用程序。当我尝试从另一个应用程序（也是烧瓶）向此 API 发送获取请求时，它返回以下错误

Traceback (most recent call last):
  File "/usr/local/lib/python3.6/dist-packages/urllib3/connection.py", line 170, in _new_conn
    (self._dns_host, self.port), self.timeout, **extra_kw
  File "/usr/local/lib/python3.6/dist-packages/urllib3/util/connection.py", line 73, in create_connection
    for res in socket.getaddrinfo(host, port, family, socket.SOCK_STREAM):
  File "/usr/lib/python3.6/socket.py", line 745, in getaddrinfo
    for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
socket.gaierror: [Errno -2] Name or service not known

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.6/dist-packages/urllib3/connectionpool.py", line 706, in urlopen
    chunked=chunked,
  File "/usr/local/lib/python3.6/dist-packages/urllib3/connectionpool.py", line 382, in _make_request
    self._validate_conn(conn)
  File "/usr/local/lib/python3.6/dist-packages/urllib3/connectionpool.py", line 1010, in _validate_conn
    conn.connect()
  File "/usr/local/lib/python3.6/dist-packages/urllib3/connection.py", line 353, in connect
    conn = self._new_conn()
  File "/usr/local/lib/python3.6/dist-packages/urllib3/connection.py", line 182, in _new_conn
    self, "Failed to establish a new connection: %s" % e
urllib3.exceptions.NewConnectionError: <urllib3.connection.HTTPSConnection object at 0x7f6f965d9358>: Failed to establish a new connection: [Errno -2] Name or service not known

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.6/dist-packages/urllib3/util/retry.py", line 574, in increment
    raise MaxRetryError(_pool, url, error or ResponseError(cause))
urllib3.exceptions.MaxRetryError: HTTPSConnectionPool(host='data-collector.cloud', port=443): Max retries exceeded with url: /sample_url (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7f6f965d9358>: Failed to establish a new connection: [Errno -2] Name or service not known',))

我认为发生此错误是因为我向 API 发送了太多具有相同 url 的请求。然后我通过添加限制了 API 调用的数量 decorators = [index.limiter.limit("60/minute")] API。然而，错误仍然存在。然后我认为该错误可能是由服务器接受的调用量引起的。我认为在进行 API 调用后我没有正确关闭连接。所以我加了

from requests.packages.urllib3 import Retry, PoolManager

retries = Retry(connect=5, read=2, redirect=5)
with PoolManager(retries=retries) as http:
    response = http.request('GET', url)

但这也没有解决我的问题。我在这里想念什么？我正在使用python3.8

编辑：我发现它本身不是导致它的查询，因为如果我尝试其他查询，则会弹出相同的消息。我仍然不知道如何调试这个：/

【问题讨论】：

解决方案：确实是 DNS 问题。我必须指定应用程序的环境变量名称，而不是 data-collector.cloud。
你是如何指定环境变量名的？介意带我走几步吗？谢谢！

标签： python api urllib httpurlconnection flask-restful

【解决方案1】：

错误提示：“名称或服务未知”。换句话说，这是一个名称解析问题 (DNS)。

交叉检查目标主机（“data-collector.cloud”，不在公共 DNS 记录中。）

【讨论】：