We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
snap_config.prepare_env can hang forever if snapd is malfunctioning
Reported at https://community.letsencrypt.org/t/sudo-certbot-renew-hangs-forever/138649

There's some evidence in that thread that `snapd` can get into a state where it just stops responding to commands (whether via `snap`, `snapctl`, or the REST API directly).

Certbot should guard against the possibility of hanging forever, by setting timeouts on relevant network operations:

https://github.com/certbot/certbot/blob/9ca7f76505b10b2f395ddffc4ddc1cbc8afb516b/certbot/certbot/_internal/snap_config.py#L87-L89

https://github.com/certbot/certbot/blob/9ca7f76505b10b2f395ddffc4ddc1cbc8afb516b/certbot/certbot/_internal/snap_config.py#L56-L57

Edit: to clarify, although the reported issue involves the previous shell-based snap wrapper, I have reproduced the same hang and lack of effective timeout with the current Python implementation.

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `certbot/certbot/_internal/snap_config.py`
Content:
```
1 """Module configuring Certbot in a snap environment"""
2 import logging
3 import socket
4 from typing import Iterable
5 from typing import List
6 from typing import Optional
7 
8 from requests import Session
9 from requests.adapters import HTTPAdapter
10 from requests.exceptions import HTTPError
11 from requests.exceptions import RequestException
12 
13 from certbot.compat import os
14 from certbot.errors import Error
15 
16 try:
17     from urllib3.connection import HTTPConnection
18     from urllib3.connectionpool import HTTPConnectionPool
19 except ImportError:
20     # Stub imports for oldest requirements, that will never be used in snaps.
21     HTTPConnection = object  # type: ignore[misc,assignment]
22     HTTPConnectionPool = object  # type: ignore[misc,assignment]
23 
24 
25 _ARCH_TRIPLET_MAP = {
26     'arm64': 'aarch64-linux-gnu',
27     'armhf': 'arm-linux-gnueabihf',
28     'i386': 'i386-linux-gnu',
29     'ppc64el': 'powerpc64le-linux-gnu',
30     'powerpc': 'powerpc-linux-gnu',
31     'amd64': 'x86_64-linux-gnu',
32     's390x': 's390x-linux-gnu',
33 }
34 
35 LOGGER = logging.getLogger(__name__)
36 
37 
38 def prepare_env(cli_args: List[str]) -> List[str]:
39     """
40     Prepare runtime environment for a certbot execution in snap.
41     :param list cli_args: List of command line arguments
42     :return: Update list of command line arguments
43     :rtype: list
44     """
45     snap_arch = os.environ.get('SNAP_ARCH')
46 
47     if snap_arch not in _ARCH_TRIPLET_MAP:
48         raise Error('Unrecognized value of SNAP_ARCH: {0}'.format(snap_arch))
49 
50     os.environ['CERTBOT_AUGEAS_PATH'] = '{0}/usr/lib/{1}/libaugeas.so.0'.format(
51         os.environ.get('SNAP'), _ARCH_TRIPLET_MAP[snap_arch])
52 
53     with Session() as session:
54         session.mount('http://snapd/', _SnapdAdapter())
55 
56         try:
57             response = session.get('http://snapd/v2/connections?snap=certbot&interface=content')
58             response.raise_for_status()
59         except RequestException as e:
60             if isinstance(e, HTTPError) and e.response.status_code == 404:
61                 LOGGER.error('An error occurred while fetching Certbot snap plugins: '
62                              'your version of snapd is outdated.')
63                 LOGGER.error('Please run "sudo snap install core; sudo snap refresh core" '
64                              'in your terminal and try again.')
65             else:
66                 LOGGER.error('An error occurred while fetching Certbot snap plugins: '
67                              'make sure the snapd service is running.')
68             raise e
69 
70     data = response.json()
71     connections = ['/snap/{0}/current/lib/python3.8/site-packages/'.format(item['slot']['snap'])
72                    for item in data.get('result', {}).get('established', [])
73                    if item.get('plug', {}).get('plug') == 'plugin'
74                    and item.get('plug-attrs', {}).get('content') == 'certbot-1']
75 
76     os.environ['CERTBOT_PLUGIN_PATH'] = ':'.join(connections)
77 
78     cli_args.append('--preconfigured-renewal')
79 
80     return cli_args
81 
82 
83 class _SnapdConnection(HTTPConnection):
84     def __init__(self) -> None:
85         super().__init__("localhost")
86         self.sock: Optional[socket.socket] = None
87 
88     def connect(self) -> None:
89         self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
90         self.sock.connect("/run/snapd.socket")
91 
92 
93 class _SnapdConnectionPool(HTTPConnectionPool):
94     def __init__(self) -> None:
95         super().__init__("localhost")
96 
97     def _new_conn(self) -> _SnapdConnection:
98         return _SnapdConnection()
99 
100 
101 class _SnapdAdapter(HTTPAdapter):
102     def get_connection(self, url: str,
103                        proxies: Optional[Iterable[str]] = None) -> _SnapdConnectionPool:
104         return _SnapdConnectionPool()
105
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/certbot/certbot/_internal/snap_config.py b/certbot/certbot/_internal/snap_config.py
--- a/certbot/certbot/_internal/snap_config.py
+++ b/certbot/certbot/_internal/snap_config.py
@@ -54,7 +54,8 @@
         session.mount('http://snapd/', _SnapdAdapter())
 
         try:
-            response = session.get('http://snapd/v2/connections?snap=certbot&interface=content')
+            response = session.get('http://snapd/v2/connections?snap=certbot&interface=content',
+                                   timeout=30.0)
             response.raise_for_status()
         except RequestException as e:
             if isinstance(e, HTTPError) and e.response.status_code == 404:

{"golden_diff": "diff --git a/certbot/certbot/_internal/snap_config.py b/certbot/certbot/_internal/snap_config.py\n--- a/certbot/certbot/_internal/snap_config.py\n+++ b/certbot/certbot/_internal/snap_config.py\n@@ -54,7 +54,8 @@\n         session.mount('http://snapd/', _SnapdAdapter())\n \n         try:\n-            response = session.get('http://snapd/v2/connections?snap=certbot&interface=content')\n+            response = session.get('http://snapd/v2/connections?snap=certbot&interface=content',\n+                                   timeout=30.0)\n             response.raise_for_status()\n         except RequestException as e:\n             if isinstance(e, HTTPError) and e.response.status_code == 404:\n", "issue": "snap_config.prepare_env can hang forever if snapd is malfunctioning\nReported at https://community.letsencrypt.org/t/sudo-certbot-renew-hangs-forever/138649\r\n\r\nThere's some evidence in that thread that `snapd` can get into a state where it just stops responding to commands (whether via `snap`, `snapctl`, or the REST API directly).\r\n\r\nCertbot should guard against the possibility of hanging forever, by setting timeouts on relevant network operations:\r\n\r\nhttps://github.com/certbot/certbot/blob/9ca7f76505b10b2f395ddffc4ddc1cbc8afb516b/certbot/certbot/_internal/snap_config.py#L87-L89\r\n\r\nhttps://github.com/certbot/certbot/blob/9ca7f76505b10b2f395ddffc4ddc1cbc8afb516b/certbot/certbot/_internal/snap_config.py#L56-L57\r\n\r\nEdit: to clarify, although the reported issue involves the previous shell-based snap wrapper, I have reproduced the same hang and lack of effective timeout with the current Python implementation.\n", "before_files": [{"content": "\"\"\"Module configuring Certbot in a snap environment\"\"\"\nimport logging\nimport socket\nfrom typing import Iterable\nfrom typing import List\nfrom typing import Optional\n\nfrom requests import Session\nfrom requests.adapters import HTTPAdapter\nfrom requests.exceptions import HTTPError\nfrom requests.exceptions import RequestException\n\nfrom certbot.compat import os\nfrom certbot.errors import Error\n\ntry:\n    from urllib3.connection import HTTPConnection\n    from urllib3.connectionpool import HTTPConnectionPool\nexcept ImportError:\n    # Stub imports for oldest requirements, that will never be used in snaps.\n    HTTPConnection = object  # type: ignore[misc,assignment]\n    HTTPConnectionPool = object  # type: ignore[misc,assignment]\n\n\n_ARCH_TRIPLET_MAP = {\n    'arm64': 'aarch64-linux-gnu',\n    'armhf': 'arm-linux-gnueabihf',\n    'i386': 'i386-linux-gnu',\n    'ppc64el': 'powerpc64le-linux-gnu',\n    'powerpc': 'powerpc-linux-gnu',\n    'amd64': 'x86_64-linux-gnu',\n    's390x': 's390x-linux-gnu',\n}\n\nLOGGER = logging.getLogger(__name__)\n\n\ndef prepare_env(cli_args: List[str]) -> List[str]:\n    \"\"\"\n    Prepare runtime environment for a certbot execution in snap.\n    :param list cli_args: List of command line arguments\n    :return: Update list of command line arguments\n    :rtype: list\n    \"\"\"\n    snap_arch = os.environ.get('SNAP_ARCH')\n\n    if snap_arch not in _ARCH_TRIPLET_MAP:\n        raise Error('Unrecognized value of SNAP_ARCH: {0}'.format(snap_arch))\n\n    os.environ['CERTBOT_AUGEAS_PATH'] = '{0}/usr/lib/{1}/libaugeas.so.0'.format(\n        os.environ.get('SNAP'), _ARCH_TRIPLET_MAP[snap_arch])\n\n    with Session() as session:\n        session.mount('http://snapd/', _SnapdAdapter())\n\n        try:\n            response = session.get('http://snapd/v2/connections?snap=certbot&interface=content')\n            response.raise_for_status()\n        except RequestException as e:\n            if isinstance(e, HTTPError) and e.response.status_code == 404:\n                LOGGER.error('An error occurred while fetching Certbot snap plugins: '\n                             'your version of snapd is outdated.')\n                LOGGER.error('Please run \"sudo snap install core; sudo snap refresh core\" '\n                             'in your terminal and try again.')\n            else:\n                LOGGER.error('An error occurred while fetching Certbot snap plugins: '\n                             'make sure the snapd service is running.')\n            raise e\n\n    data = response.json()\n    connections = ['/snap/{0}/current/lib/python3.8/site-packages/'.format(item['slot']['snap'])\n                   for item in data.get('result', {}).get('established', [])\n                   if item.get('plug', {}).get('plug') == 'plugin'\n                   and item.get('plug-attrs', {}).get('content') == 'certbot-1']\n\n    os.environ['CERTBOT_PLUGIN_PATH'] = ':'.join(connections)\n\n    cli_args.append('--preconfigured-renewal')\n\n    return cli_args\n\n\nclass _SnapdConnection(HTTPConnection):\n    def __init__(self) -> None:\n        super().__init__(\"localhost\")\n        self.sock: Optional[socket.socket] = None\n\n    def connect(self) -> None:\n        self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)\n        self.sock.connect(\"/run/snapd.socket\")\n\n\nclass _SnapdConnectionPool(HTTPConnectionPool):\n    def __init__(self) -> None:\n        super().__init__(\"localhost\")\n\n    def _new_conn(self) -> _SnapdConnection:\n        return _SnapdConnection()\n\n\nclass _SnapdAdapter(HTTPAdapter):\n    def get_connection(self, url: str,\n                       proxies: Optional[Iterable[str]] = None) -> _SnapdConnectionPool:\n        return _SnapdConnectionPool()\n", "path": "certbot/certbot/_internal/snap_config.py"}], "after_files": [{"content": "\"\"\"Module configuring Certbot in a snap environment\"\"\"\nimport logging\nimport socket\nfrom typing import Iterable\nfrom typing import List\nfrom typing import Optional\n\nfrom requests import Session\nfrom requests.adapters import HTTPAdapter\nfrom requests.exceptions import HTTPError\nfrom requests.exceptions import RequestException\n\nfrom certbot.compat import os\nfrom certbot.errors import Error\n\ntry:\n    from urllib3.connection import HTTPConnection\n    from urllib3.connectionpool import HTTPConnectionPool\nexcept ImportError:\n    # Stub imports for oldest requirements, that will never be used in snaps.\n    HTTPConnection = object  # type: ignore[misc,assignment]\n    HTTPConnectionPool = object  # type: ignore[misc,assignment]\n\n\n_ARCH_TRIPLET_MAP = {\n    'arm64': 'aarch64-linux-gnu',\n    'armhf': 'arm-linux-gnueabihf',\n    'i386': 'i386-linux-gnu',\n    'ppc64el': 'powerpc64le-linux-gnu',\n    'powerpc': 'powerpc-linux-gnu',\n    'amd64': 'x86_64-linux-gnu',\n    's390x': 's390x-linux-gnu',\n}\n\nLOGGER = logging.getLogger(__name__)\n\n\ndef prepare_env(cli_args: List[str]) -> List[str]:\n    \"\"\"\n    Prepare runtime environment for a certbot execution in snap.\n    :param list cli_args: List of command line arguments\n    :return: Update list of command line arguments\n    :rtype: list\n    \"\"\"\n    snap_arch = os.environ.get('SNAP_ARCH')\n\n    if snap_arch not in _ARCH_TRIPLET_MAP:\n        raise Error('Unrecognized value of SNAP_ARCH: {0}'.format(snap_arch))\n\n    os.environ['CERTBOT_AUGEAS_PATH'] = '{0}/usr/lib/{1}/libaugeas.so.0'.format(\n        os.environ.get('SNAP'), _ARCH_TRIPLET_MAP[snap_arch])\n\n    with Session() as session:\n        session.mount('http://snapd/', _SnapdAdapter())\n\n        try:\n            response = session.get('http://snapd/v2/connections?snap=certbot&interface=content',\n                                   timeout=30.0)\n            response.raise_for_status()\n        except RequestException as e:\n            if isinstance(e, HTTPError) and e.response.status_code == 404:\n                LOGGER.error('An error occurred while fetching Certbot snap plugins: '\n                             'your version of snapd is outdated.')\n                LOGGER.error('Please run \"sudo snap install core; sudo snap refresh core\" '\n                             'in your terminal and try again.')\n            else:\n                LOGGER.error('An error occurred while fetching Certbot snap plugins: '\n                             'make sure the snapd service is running.')\n            raise e\n\n    data = response.json()\n    connections = ['/snap/{0}/current/lib/python3.8/site-packages/'.format(item['slot']['snap'])\n                   for item in data.get('result', {}).get('established', [])\n                   if item.get('plug', {}).get('plug') == 'plugin'\n                   and item.get('plug-attrs', {}).get('content') == 'certbot-1']\n\n    os.environ['CERTBOT_PLUGIN_PATH'] = ':'.join(connections)\n\n    cli_args.append('--preconfigured-renewal')\n\n    return cli_args\n\n\nclass _SnapdConnection(HTTPConnection):\n    def __init__(self) -> None:\n        super().__init__(\"localhost\")\n        self.sock: Optional[socket.socket] = None\n\n    def connect(self) -> None:\n        self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)\n        self.sock.connect(\"/run/snapd.socket\")\n\n\nclass _SnapdConnectionPool(HTTPConnectionPool):\n    def __init__(self) -> None:\n        super().__init__(\"localhost\")\n\n    def _new_conn(self) -> _SnapdConnection:\n        return _SnapdConnection()\n\n\nclass _SnapdAdapter(HTTPAdapter):\n    def get_connection(self, url: str,\n                       proxies: Optional[Iterable[str]] = None) -> _SnapdConnectionPool:\n        return _SnapdConnectionPool()\n", "path": "certbot/certbot/_internal/snap_config.py"}]}