Merge #2562

2562: Dynamic address resolution everywhere r=mergify[bot] a=nextgens

## What type of PR?

enhancement

## What does this PR do?

Use dynamic address resolution everywhere.
Derive a new key for admin/SECRET_KEY
Cleanup the environment

This should allow restarting containers.

### Related issue(s)
- closes #1341
- closes #1013
- closes #1430

## Prerequisites
Before we can consider review and merge, please make sure the following list is done and checked.
If an entry in not applicable, you can check it or remove it from the list.

- [x] In case of feature or enhancement: documentation updated accordingly
- [x] Unless it's docs or a minor change: add [changelog](https://mailu.io/master/contributors/workflow.html#changelog) entry file.


Co-authored-by: Florent Daigniere <nextgens@freenetproject.org>

core/admin/mailu/configuration.py

@@ -1,7 +1,6 @@
 import os
 
 from datetime import timedelta
-from socrate import system
 import ipaddress
 
 DEFAULT_CONFIG = {
@@ -83,17 +82,6 @@ DEFAULT_CONFIG = {
     'PROXY_AUTH_WHITELIST': '',
     'PROXY_AUTH_HEADER': 'X-Auth-Email',
     'PROXY_AUTH_CREATE': False,
-    # Host settings
-    'HOST_IMAP': 'imap',
-    'HOST_LMTP': 'imap:2525',
-    'HOST_POP3': 'imap',
-    'HOST_SMTP': 'smtp',
-    'HOST_AUTHSMTP': 'smtp',
-    'HOST_ADMIN': 'admin',
-    'HOST_WEBMAIL': 'webmail',
-    'HOST_WEBDAV': 'webdav:5232',
-    'HOST_REDIS': 'redis',
-    'HOST_FRONT': 'front',
     'SUBNET': '192.168.203.0/24',
     'SUBNET6': None
 }
@@ -111,19 +99,6 @@ class ConfigManager:
     def __init__(self):
         self.config = dict()
 
-    def get_host_address(self, name):
-        # if MYSERVICE_ADDRESS is defined, use this
-        if f'{name}_ADDRESS' in os.environ:
-            return os.environ.get(f'{name}_ADDRESS')
-        # otherwise use the host name and resolve it
-        return system.resolve_address(self.config[f'HOST_{name}'])
-
-    def resolve_hosts(self):
-        for key in ['IMAP', 'POP3', 'AUTHSMTP', 'SMTP', 'REDIS']:
-            self.config[f'{key}_ADDRESS'] = self.get_host_address(key)
-        if self.config['WEBMAIL'] != 'none':
-            self.config['WEBMAIL_ADDRESS'] = self.get_host_address('WEBMAIL')
-
     def __get_env(self, key, value):
         key_file = key + "_FILE"
         if key_file in os.environ:
@@ -144,11 +119,14 @@ class ConfigManager:
         # get current app config
         self.config.update(app.config)
         # get environment variables
+        for key in os.environ:
+            if key.endswith('_ADDRESS'):
+                self.config[key] = os.environ[key]
+
         self.config.update({
             key: self.__coerce_value(self.__get_env(key, value))
             for key, value in DEFAULT_CONFIG.items()
         })
-        self.resolve_hosts()
 
         # automatically set the sqlalchemy string
         if self.config['DB_FLAVOR']: