[IMP] base, mail: make outgoing mail server configuration more user friendly

PURPOSE

Ease the configuration of external email servers by adding links to the
documentation and by making errors more user friendly.

SPECIFICATIONS

This is done by catching more exceptions when testing outgoing mail server
connection and giving related hints.

A link to the documentation is also added in mail: Settings > External Email
Servers feature: add a link to this doc: https://www.odoo.com/documentation/user/13.0/discuss/advanced/email_servers.html

Task ID-2273671
PR #54176

X-original-commit: d30682f4d4aeaefa077ba284a60c93f3a020365f

addons/mail/views/res_config_settings_views.xml

@@ -31,6 +31,7 @@
                             </div>
                             <div class="o_setting_right_pane">
                                 <label for="external_email_server_default"/>
+                                <a href="https://www.odoo.com/documentation/user/13.0/discuss/advanced/email_servers.html" title="Documentation" class="o_doc_link" target="_blank"></a>
                                 <div class="text-muted" id="external_email_server_default">
                                     Configure your own email servers
                                 </div>

odoo/addons/base/models/ir_mail_server.py

@@ -9,6 +9,8 @@ import email.policy
 import logging
 import re
 import smtplib
+from socket import gaierror, timeout
+from ssl import SSLError
 import sys
 import threading
 
@@ -129,6 +131,18 @@ class IrMailServer(models.Model):
             except UserError as e:
                 # let UserErrors (messages) bubble up
                 raise e
+            except UnicodeError as e:
+                raise UserError(_("Invalid server name !\n %s", ustr(e)))
+            except (gaierror, timeout) as e:
+                raise UserError(_("No response received. Check server address and port number.\n %s", ustr(e)))
+            except smtplib.SMTPServerDisconnected as e:
+                raise UserError(_("The server has closed the connection unexpectedly. Check configuration served on this port number.\n %s", ustr(e.strerror)))
+            except smtplib.SMTPResponseException as e:
+                raise UserError(_("Server replied with following exception:\n %s", ustr(e.smtp_error)))
+            except smtplib.SMTPException as e:
+                raise UserError(_("An SMTP exception occurred. Check port number and connection security type.\n %s", ustr(e.smtp_error)))
+            except SSLError as e:
+                raise UserError(_("An SSL exception occurred. Check connection security type.\n %s", ustr(e)))
             except Exception as e:
                 raise UserError(_("Connection Test Failed! Here is what we got instead:\n %s", ustr(e)))
             finally: