From 289a77e906db6995123793dd9c1546ef4349287f Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 19 Jul 2023 15:31:17 +0200
Subject: [PATCH 01/32] add notification

---
 config.py        | 39 +++++++++++++++++++++++++++++++++++++++
 dbsync_daemon.py |  5 ++++-
 log_functions.py | 24 ++++++++++++++++++++++++
 3 files changed, 67 insertions(+), 1 deletion(-)

diff --git a/config.py b/config.py
index 1098b7a..8106679 100644
--- a/config.py
+++ b/config.py
@@ -13,6 +13,8 @@
 import tempfile
 import pathlib
 import subprocess
+import smtplib
+import socket
 
 config = Dynaconf(
     envvar_prefix=False,
@@ -100,6 +102,43 @@ def validate_config(config):
             ):
                 raise ConfigError("Config error: Ignored tables parameter should be a list")
 
+    if "notification" in config:
+        settings = [
+            "smtp_server",
+            "smtp_username",
+            "smtp_password",
+            "email_sender",
+            "email_subject",
+            "email_recipients",
+        ]
+
+        for setting in settings:
+            if setting not in config.notification:
+                raise ConfigError(f"Config error: `{setting}` is missing from `notification`.")
+
+        if not isinstance(config.notification.email_recipients, list):
+            raise ConfigError("Config error: `email_recipients` should be list of address.")
+
+        smtp_conn: smtplib.SMTP = None
+
+        try:
+            smtp_conn = smtplib.SMTP(config.notification.smtp_server)
+        except socket.gaierror:
+            raise ConfigError(f"Config error: Cannot connect to SMTP server: `{config.notification.smtp_server}`.")
+
+        try:
+            smtp_conn.login(config.notification.smtp_username, config.notification.smtp_password)
+        except smtplib.SMTPAuthenticationError:
+            raise ConfigError(
+                f"Config error: Cannot login to SMTP server with user: `{config.notification.smtp_username}` and a specified password."
+            )
+
+
+def can_send_email(config: Dynaconf) -> bool:
+    if "notification" in config:
+        return True
+    return False
+
 
 def get_ignored_tables(
     connection,
diff --git a/dbsync_daemon.py b/dbsync_daemon.py
index 785d050..bdf9f47 100644
--- a/dbsync_daemon.py
+++ b/dbsync_daemon.py
@@ -21,9 +21,10 @@
     validate_config,
     ConfigError,
     update_config_path,
+    can_send_email,
 )
 
-from log_functions import setup_logger, handle_error_and_exit
+from log_functions import setup_logger, handle_error_and_exit, send_email
 
 
 def is_pyinstaller() -> bool:
@@ -171,6 +172,8 @@ def main():
 
             except dbsync.DbSyncError as e:
                 logging.error(str(e))
+                if can_send_email(config):
+                    send_email(str(e), datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S"))
 
             logging.debug("Going to sleep")
             time.sleep(sleep_time)
diff --git a/log_functions.py b/log_functions.py
index 40125d7..42ea935 100644
--- a/log_functions.py
+++ b/log_functions.py
@@ -2,6 +2,11 @@
 import pathlib
 import sys
 import typing
+import smtplib
+from email.mime.multipart import MIMEMultipart
+from email.mime.text import MIMEText
+
+from config import config
 
 
 def filter_below_error(record):
@@ -47,3 +52,22 @@ def log_verbosity_to_logging(verbosity: str):
 def handle_error_and_exit(error: typing.Union[str, Exception]):
     logging.error(str(error))
     sys.exit(1)
+
+
+def send_email(error: str, date_time: str = None) -> None:
+    smtp_conn = smtplib.SMTP(config.notification.smtp_server)
+    smtp_conn.login(config.notification.smtp_username, config.notification.smtp_password)
+
+    msg = MIMEMultipart()
+    msg["Subject"] = config.notification.email_subject
+    msg["From"] = config.notification.email_sender
+    msg["To"] = ", ".join(config.notification.email_recipients)
+    msg.preamble = error
+
+    if date_time:
+        error = f"{date_time}: {error}"
+
+    msg.attach(MIMEText(error, "plain"))
+
+    smtp_conn.sendmail(config.notification.smtp_username, config.notification.email_recipients, msg.as_string())
+    smtp_conn.quit()

From 99377869e08b5eca4f9d959e9fde97dcf8d60400 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 21 Jul 2023 11:47:10 +0200
Subject: [PATCH 02/32] move function

---
 config.py        | 6 ------
 dbsync_daemon.py | 8 ++++++--
 log_functions.py | 8 ++++++++
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/config.py b/config.py
index 8106679..767d134 100644
--- a/config.py
+++ b/config.py
@@ -134,12 +134,6 @@ def validate_config(config):
             )
 
 
-def can_send_email(config: Dynaconf) -> bool:
-    if "notification" in config:
-        return True
-    return False
-
-
 def get_ignored_tables(
     connection,
 ):
diff --git a/dbsync_daemon.py b/dbsync_daemon.py
index bdf9f47..c46bdea 100644
--- a/dbsync_daemon.py
+++ b/dbsync_daemon.py
@@ -21,10 +21,14 @@
     validate_config,
     ConfigError,
     update_config_path,
-    can_send_email,
 )
 
-from log_functions import setup_logger, handle_error_and_exit, send_email
+from log_functions import (
+    setup_logger,
+    handle_error_and_exit,
+    send_email,
+    can_send_email,
+)
 
 
 def is_pyinstaller() -> bool:
diff --git a/log_functions.py b/log_functions.py
index 42ea935..dbfec20 100644
--- a/log_functions.py
+++ b/log_functions.py
@@ -6,6 +6,8 @@
 from email.mime.multipart import MIMEMultipart
 from email.mime.text import MIMEText
 
+from dynaconf import Dynaconf
+
 from config import config
 
 
@@ -71,3 +73,9 @@ def send_email(error: str, date_time: str = None) -> None:
 
     smtp_conn.sendmail(config.notification.smtp_username, config.notification.email_recipients, msg.as_string())
     smtp_conn.quit()
+
+
+def can_send_email(config: Dynaconf) -> bool:
+    if "notification" in config:
+        return True
+    return False

From c16102befcdf144e1ca5506be9e1552a431bc9ac Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 21 Jul 2023 12:10:19 +0200
Subject: [PATCH 03/32] add tests

---
 test/test_config.py | 58 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/test/test_config.py b/test/test_config.py
index c8badfc..2b91a4f 100644
--- a/test/test_config.py
+++ b/test/test_config.py
@@ -13,6 +13,7 @@
     validate_config,
     get_ignored_tables,
 )
+from log_functions import can_send_email
 
 from .conftest import (
     _reset_config,
@@ -256,3 +257,60 @@ def test_get_ignored_tables():
     validate_config(config)
     ignored_tables = get_ignored_tables(config.connections[0])
     assert ignored_tables == ["table"]
+
+
+def test_config_notification_setup():
+    _reset_config()
+
+    # no NOTIFICATIONS set should pass but cannot send email
+    validate_config(config)
+    assert can_send_email(config) is False
+
+    # incomplete setting
+    config.update(
+        {
+            "NOTIFICATION": {
+                "smtp_server": "server",
+                "smtp_username": "user",
+            }
+        }
+    )
+
+    with pytest.raises(ConfigError, match="Config error: `smtp_password`"):
+        validate_config(config)
+
+    # another incomplete setting
+    _reset_config()
+
+    config.update(
+        {
+            "NOTIFICATION": {
+                "smtp_server": "server",
+                "smtp_username": "user",
+                "smtp_password": "pass",
+            }
+        }
+    )
+
+    with pytest.raises(ConfigError, match="Config error: `email_sender`"):
+        validate_config(config)
+
+    # complete setting but does not work
+    config.update(
+        {
+            "NOTIFICATION": {
+                "smtp_server": "server",
+                "smtp_username": "user",
+                "smtp_password": "pass",
+                "email_sender": "dbsync@sync.com",
+                "email_subject": "DB Sync Error",
+                "email_recipients": ["recipient1@test.com", "recipient2@test.com"],
+            }
+        }
+    )
+
+    with pytest.raises(ConfigError, match="Config error: Cannot connect to SMTP server"):
+        validate_config(config)
+
+    # notifications are set, emails can be send - but this config was not validated, as it would be in real run
+    assert can_send_email(config)

From a6360ce113395202817a4ec46fbef98f6eccef1c Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 21 Jul 2023 12:13:45 +0200
Subject: [PATCH 04/32] only send email if previous error message was not the
 same as current

---
 dbsync_daemon.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/dbsync_daemon.py b/dbsync_daemon.py
index c46bdea..1f31f1e 100644
--- a/dbsync_daemon.py
+++ b/dbsync_daemon.py
@@ -153,6 +153,8 @@ def main():
             handle_error_and_exit(e)
 
     else:
+        error_msg = None
+
         if not args.skip_init:
             try:
                 dbsync.dbsync_init(mc)
@@ -176,8 +178,9 @@ def main():
 
             except dbsync.DbSyncError as e:
                 logging.error(str(e))
-                if can_send_email(config):
+                if can_send_email(config) and error_msg != str(e):
                     send_email(str(e), datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S"))
+                    error_msg = str(e)
 
             logging.debug("Going to sleep")
             time.sleep(sleep_time)

From cb6ecd08687ac6e9072ce96b61007f40050f7082 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 21 Jul 2023 12:18:42 +0200
Subject: [PATCH 05/32] add notification setting example

---
 config.yaml.default | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/config.yaml.default b/config.yaml.default
index 1d5f03b..1d7035f 100644
--- a/config.yaml.default
+++ b/config.yaml.default
@@ -29,3 +29,18 @@ connections:
 daemon:
   # How often to synchronize (in seconds)
   sleep_time: 10
+
+# optional setting, if you do not want notifications on sync errors to be send via email just delete this section
+notification:
+  # address of stmp server to send emails
+  smtp_server: "xxx.xxx"
+  # smtp server user
+  smtp_username: "user@email.xxx"
+  # smtp user's password
+  smtp_password: "password"
+  # email sender to be displayed in the message
+  email_sender: "dbsync@info.com"
+  # email subject
+  email_subject: "DB Sync Error"
+  # list of recipients of the email notification
+  email_recipients: ["recipient1@email.xxx", "recipient1@email.xxx"]
\ No newline at end of file

From 087390ec109046b66ea2200a3e7540490d03edcf Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 21 Jul 2023 12:22:38 +0200
Subject: [PATCH 06/32] fix typo

---
 config.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.py b/config.py
index 767d134..5527f6b 100644
--- a/config.py
+++ b/config.py
@@ -117,7 +117,7 @@ def validate_config(config):
                 raise ConfigError(f"Config error: `{setting}` is missing from `notification`.")
 
         if not isinstance(config.notification.email_recipients, list):
-            raise ConfigError("Config error: `email_recipients` should be list of address.")
+            raise ConfigError("Config error: `email_recipients` should be list of addresses.")
 
         smtp_conn: smtplib.SMTP = None
 

From ee6ca5c79dab2626926dd72b4de6e1ea38343bd8 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 09:15:15 +0200
Subject: [PATCH 07/32] fix error messages

---
 config.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/config.py b/config.py
index 5527f6b..37620cc 100644
--- a/config.py
+++ b/config.py
@@ -123,14 +123,15 @@ def validate_config(config):
 
         try:
             smtp_conn = smtplib.SMTP(config.notification.smtp_server)
-        except socket.gaierror:
+        except OSError:
             raise ConfigError(f"Config error: Cannot connect to SMTP server: `{config.notification.smtp_server}`.")
 
         try:
             smtp_conn.login(config.notification.smtp_username, config.notification.smtp_password)
-        except smtplib.SMTPAuthenticationError:
+        except smtplib.SMTPAuthenticationError as e:
             raise ConfigError(
                 f"Config error: Cannot login to SMTP server with user: `{config.notification.smtp_username}` and a specified password."
+                f"SMTP Error: {str(e.smtp_error)}."
             )
 
 

From 8aded713e0e918837456b6a6a47f4b9403511a44 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:22:56 +0200
Subject: [PATCH 08/32] password and user are optional

---
 config.py | 2 --
 1 file changed, 2 deletions(-)

diff --git a/config.py b/config.py
index 37620cc..34299a6 100644
--- a/config.py
+++ b/config.py
@@ -105,8 +105,6 @@ def validate_config(config):
     if "notification" in config:
         settings = [
             "smtp_server",
-            "smtp_username",
-            "smtp_password",
             "email_sender",
             "email_subject",
             "email_recipients",

From be36fcf1f095b1ebc1ee2dd846938975448ad243 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:23:20 +0200
Subject: [PATCH 09/32] new config

---
 config.py | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/config.py b/config.py
index 34299a6..5518fc1 100644
--- a/config.py
+++ b/config.py
@@ -117,6 +117,18 @@ def validate_config(config):
         if not isinstance(config.notification.email_recipients, list):
             raise ConfigError("Config error: `email_recipients` should be list of addresses.")
 
+        if "use_ssl" in config.notification:
+            if not isinstance(config.notification.use_ssl, bool):
+                raise ConfigError("`use_ssl` must be set to either `true` or `false`.")
+
+        if "use_tls" in config.notification:
+            if not isinstance(config.notification.use_tls, bool):
+                raise ConfigError("`use_tls` must be set to either `true` or `false`.")
+
+        if "smtp_port" in config.notification:
+            if not isinstance(config.notification.smtp_port, int):
+                raise ConfigError("`smtp_port` must be set an integer.")
+
         smtp_conn: smtplib.SMTP = None
 
         try:

From 664b83d00c17a4fb6bd41ca900ad6428fd6099b7 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:24:07 +0200
Subject: [PATCH 10/32] move smtp functions to separate file

---
 log_functions.py  | 28 ----------------------
 smtp_functions.py | 59 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 28 deletions(-)
 create mode 100644 smtp_functions.py

diff --git a/log_functions.py b/log_functions.py
index dbfec20..bbe657b 100644
--- a/log_functions.py
+++ b/log_functions.py
@@ -2,9 +2,6 @@
 import pathlib
 import sys
 import typing
-import smtplib
-from email.mime.multipart import MIMEMultipart
-from email.mime.text import MIMEText
 
 from dynaconf import Dynaconf
 
@@ -54,28 +51,3 @@ def log_verbosity_to_logging(verbosity: str):
 def handle_error_and_exit(error: typing.Union[str, Exception]):
     logging.error(str(error))
     sys.exit(1)
-
-
-def send_email(error: str, date_time: str = None) -> None:
-    smtp_conn = smtplib.SMTP(config.notification.smtp_server)
-    smtp_conn.login(config.notification.smtp_username, config.notification.smtp_password)
-
-    msg = MIMEMultipart()
-    msg["Subject"] = config.notification.email_subject
-    msg["From"] = config.notification.email_sender
-    msg["To"] = ", ".join(config.notification.email_recipients)
-    msg.preamble = error
-
-    if date_time:
-        error = f"{date_time}: {error}"
-
-    msg.attach(MIMEText(error, "plain"))
-
-    smtp_conn.sendmail(config.notification.smtp_username, config.notification.email_recipients, msg.as_string())
-    smtp_conn.quit()
-
-
-def can_send_email(config: Dynaconf) -> bool:
-    if "notification" in config:
-        return True
-    return False
diff --git a/smtp_functions.py b/smtp_functions.py
new file mode 100644
index 0000000..7629956
--- /dev/null
+++ b/smtp_functions.py
@@ -0,0 +1,59 @@
+import datetime
+import smtplib
+import typing
+from email.mime.multipart import MIMEMultipart
+from email.mime.text import MIMEText
+
+from dynaconf import Dynaconf
+
+
+def create_connection(config: Dynaconf) -> typing.Union[smtplib.SMTP_SSL, smtplib.SMTP]:
+    if "smtp_port" in config.notification:
+        port = config.notification.smtp_port
+    else:
+        port = smtplib.SMTP_PORT
+
+    if "use_ssl" in config.notification and config.notification.use_ssl:
+        host = smtplib.SMTP_SSL(config.notification.smtp_server, port)
+    else:
+        host = smtplib.SMTP(config.notification.smtp_server, port)
+
+    return host
+
+
+def log_smtp_user(host: typing.Union[smtplib.SMTP_SSL, smtplib.SMTP], config: Dynaconf) -> None:
+    if "use_tls" in config.notification and config.notification.use_tls:
+        host.starttls()
+    if config.notification.smtp_username and config.notification.smtp_password:
+        host.login(config.notification.smtp_username, config.notification.smtp_password)
+
+
+def send_email(error: str, config: Dynaconf) -> None:
+    smtp_conn = create_connection(config)
+
+    log_smtp_user(smtp_conn, config)
+
+    msg = MIMEMultipart()
+    msg["Subject"] = config.notification.email_subject
+    msg["From"] = config.notification.email_sender
+    msg["To"] = ", ".join(config.notification.email_recipients)
+    msg.preamble = error
+
+    date_time = datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S")
+
+    error = f"{date_time}: {error}"
+
+    msg.attach(MIMEText(error, "plain"))
+
+    sender_email = config.notification.email_sender
+    if "smtp_username" in config.notification:
+        sender_email = config.notification.smtp_username
+
+    smtp_conn.sendmail(sender_email, config.notification.email_recipients, msg.as_string())
+    smtp_conn.quit()
+
+
+def can_send_email(config: Dynaconf) -> bool:
+    if "notification" in config:
+        return True
+    return False

From 08d77c60f9eaec0e552cae9fcdf01f42bb3dcfb8 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:24:33 +0200
Subject: [PATCH 11/32] use new functions

---
 config.py | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/config.py b/config.py
index 5518fc1..c24c016 100644
--- a/config.py
+++ b/config.py
@@ -132,17 +132,16 @@ def validate_config(config):
         smtp_conn: smtplib.SMTP = None
 
         try:
-            smtp_conn = smtplib.SMTP(config.notification.smtp_server)
+            smtp_conn = create_connection(config)
         except OSError:
             raise ConfigError(f"Config error: Cannot connect to SMTP server: `{config.notification.smtp_server}`.")
 
         try:
-            smtp_conn.login(config.notification.smtp_username, config.notification.smtp_password)
+            log_smtp_user(smtp_conn, config)
         except smtplib.SMTPAuthenticationError as e:
-            raise ConfigError(
-                f"Config error: Cannot login to SMTP server with user: `{config.notification.smtp_username}` and a specified password."
-                f"SMTP Error: {str(e.smtp_error)}."
-            )
+            raise ConfigError(f"Config SMTP Error: {str(e.smtp_error)}.")
+
+        smtp_conn.quit()
 
 
 def get_ignored_tables(

From 3f3522f1fbfac2bdcc5c8252f4d4182d30d68b82 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:30:56 +0200
Subject: [PATCH 12/32] update tests

---
 test/test_config.py | 60 ++++++++++++++++++++++++++++++++++++---------
 1 file changed, 48 insertions(+), 12 deletions(-)

diff --git a/test/test_config.py b/test/test_config.py
index 2b91a4f..584579d 100644
--- a/test/test_config.py
+++ b/test/test_config.py
@@ -7,17 +7,10 @@
 """
 import pytest
 
-from config import (
-    config,
-    ConfigError,
-    validate_config,
-    get_ignored_tables,
-)
-from log_functions import can_send_email
+from config import ConfigError, config, get_ignored_tables, validate_config
+from smtp_functions import can_send_email
 
-from .conftest import (
-    _reset_config,
-)
+from .conftest import _reset_config
 
 
 def test_config():
@@ -276,7 +269,7 @@ def test_config_notification_setup():
         }
     )
 
-    with pytest.raises(ConfigError, match="Config error: `smtp_password`"):
+    with pytest.raises(ConfigError, match="Config error: `email_sender`"):
         validate_config(config)
 
     # another incomplete setting
@@ -288,13 +281,53 @@ def test_config_notification_setup():
                 "smtp_server": "server",
                 "smtp_username": "user",
                 "smtp_password": "pass",
+                "email_sender": "dbsync@info.com",
             }
         }
     )
 
-    with pytest.raises(ConfigError, match="Config error: `email_sender`"):
+    with pytest.raises(ConfigError, match="Config error: `email_subject`"):
         validate_config(config)
 
+    # bool variable test
+    _reset_config()
+
+    config.update(
+        {
+            "NOTIFICATION": {
+                "smtp_server": "server",
+                "smtp_username": "user",
+                "smtp_password": "pass",
+                "email_sender": "dbsync@info.com",
+                "email_subject": "DB Sync Error",
+                "email_recipients": ["recipient1@test.com", "recipient2@test.com"],
+                "use_ssl": "some_string",
+            }
+        }
+    )
+
+    with pytest.raises(ConfigError, match="`use_ssl` must be set to either `true` or `false`"):
+        validate_config(config)
+
+    # int variable test
+    _reset_config()
+
+    config.update(
+        {
+            "NOTIFICATION": {
+                "smtp_server": "server",
+                "smtp_username": "user",
+                "smtp_password": "pass",
+                "email_sender": "dbsync@info.com",
+                "email_subject": "DB Sync Error",
+                "email_recipients": ["recipient1@test.com", "recipient2@test.com"],
+                "smtp_port": "some_string",
+            }
+        }
+    )
+
+    with pytest.raises(ConfigError, match="`smtp_port` must be set an integer"):
+        validate_config(config)
     # complete setting but does not work
     config.update(
         {
@@ -305,6 +338,9 @@ def test_config_notification_setup():
                 "email_sender": "dbsync@sync.com",
                 "email_subject": "DB Sync Error",
                 "email_recipients": ["recipient1@test.com", "recipient2@test.com"],
+                "smtp_port": 25,
+                "use_ssl": False,
+                "use_tls": True,
             }
         }
     )

From acde9c7af74e33014f837355deee53efd74d359d Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:31:22 +0200
Subject: [PATCH 13/32] add imports

---
 config.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/config.py b/config.py
index c24c016..82e9a7a 100644
--- a/config.py
+++ b/config.py
@@ -16,6 +16,8 @@
 import smtplib
 import socket
 
+from smtp_functions import create_connection, log_smtp_user
+
 config = Dynaconf(
     envvar_prefix=False,
     settings_files=[],

From a41dbc9e672174b0a14b9df9bb177965d5f73d3e Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:33:28 +0200
Subject: [PATCH 14/32] update usage

---
 dbsync_daemon.py | 22 +++++-----------------
 1 file changed, 5 insertions(+), 17 deletions(-)

diff --git a/dbsync_daemon.py b/dbsync_daemon.py
index 1f31f1e..6024b1e 100644
--- a/dbsync_daemon.py
+++ b/dbsync_daemon.py
@@ -13,22 +13,10 @@
 import pathlib
 
 import dbsync
-from version import (
-    __version__,
-)
-from config import (
-    config,
-    validate_config,
-    ConfigError,
-    update_config_path,
-)
-
-from log_functions import (
-    setup_logger,
-    handle_error_and_exit,
-    send_email,
-    can_send_email,
-)
+from config import ConfigError, config, update_config_path, validate_config
+from log_functions import handle_error_and_exit, setup_logger
+from smtp_functions import can_send_email, send_email
+from version import __version__
 
 
 def is_pyinstaller() -> bool:
@@ -179,7 +167,7 @@ def main():
             except dbsync.DbSyncError as e:
                 logging.error(str(e))
                 if can_send_email(config) and error_msg != str(e):
-                    send_email(str(e), datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S"))
+                    send_email(str(e), config)
                     error_msg = str(e)
 
             logging.debug("Going to sleep")

From 20199b5c864494d82200c04c7b9960e261f7bbdc Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:39:56 +0200
Subject: [PATCH 15/32] use simple EmailMessage

---
 smtp_functions.py | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/smtp_functions.py b/smtp_functions.py
index 7629956..967605d 100644
--- a/smtp_functions.py
+++ b/smtp_functions.py
@@ -1,8 +1,7 @@
 import datetime
 import smtplib
 import typing
-from email.mime.multipart import MIMEMultipart
-from email.mime.text import MIMEText
+from email.message import EmailMessage
 
 from dynaconf import Dynaconf
 
@@ -33,17 +32,16 @@ def send_email(error: str, config: Dynaconf) -> None:
 
     log_smtp_user(smtp_conn, config)
 
-    msg = MIMEMultipart()
+    msg = EmailMessage()
     msg["Subject"] = config.notification.email_subject
     msg["From"] = config.notification.email_sender
     msg["To"] = ", ".join(config.notification.email_recipients)
-    msg.preamble = error
 
     date_time = datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S")
 
     error = f"{date_time}: {error}"
 
-    msg.attach(MIMEText(error, "plain"))
+    msg.set_content(error)
 
     sender_email = config.notification.email_sender
     if "smtp_username" in config.notification:

From e9b8eaa87a69ef20a20a8c2e7a370fabcb83b962 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:47:02 +0200
Subject: [PATCH 16/32] add option to send tes email

---
 dbsync_daemon.py | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/dbsync_daemon.py b/dbsync_daemon.py
index 6024b1e..aad699e 100644
--- a/dbsync_daemon.py
+++ b/dbsync_daemon.py
@@ -3,14 +3,14 @@
 # - pull
 # - push
 
-import datetime
-import sys
-import time
 import argparse
-import platform
+import datetime
 import logging
 import os
 import pathlib
+import platform
+import sys
+import time
 
 import dbsync
 from config import ConfigError, config, update_config_path, validate_config
@@ -91,6 +91,11 @@ def main():
         default="DEBUG",
         help="Set level of logging into log-file.",
     )
+    parser.add_argument(
+        "--test-notification-email",
+        action="store_true",
+        help="Send test notification email using the `notification` settings. Should be used to validate settings.",
+    )
 
     args = parser.parse_args()
 
@@ -113,6 +118,11 @@ def main():
     except ConfigError as e:
         handle_error_and_exit(e)
 
+    if args.test_notification_email:
+        send_email("Mergin DB Sync test email.", config)
+        logging.debug("Email send!")
+        sys.exit(0)
+
     if args.force_init and args.skip_init:
         handle_error_and_exit("Cannot use `--force-init` with `--skip-init` Initialization is required. ")
 

From 9a2431bbf29272441dc86838f09562ecd86d5778 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:52:58 +0200
Subject: [PATCH 17/32] fix error messages

---
 config.py           | 7 ++++---
 test/test_config.py | 4 ++--
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/config.py b/config.py
index 82e9a7a..5304d20 100644
--- a/config.py
+++ b/config.py
@@ -121,15 +121,16 @@ def validate_config(config):
 
         if "use_ssl" in config.notification:
             if not isinstance(config.notification.use_ssl, bool):
-                raise ConfigError("`use_ssl` must be set to either `true` or `false`.")
+                raise ConfigError("Config error: `use_ssl` must be set to either `true` or `false`.")
 
         if "use_tls" in config.notification:
             if not isinstance(config.notification.use_tls, bool):
-                raise ConfigError("`use_tls` must be set to either `true` or `false`.")
+                raise ConfigError("Config error: `use_tls` must be set to either `true` or `false`.")
 
         if "smtp_port" in config.notification:
             if not isinstance(config.notification.smtp_port, int):
-                raise ConfigError("`smtp_port` must be set an integer.")
+                raise ConfigError("Config error: `smtp_port` must be set an integer.")
+
 
         smtp_conn: smtplib.SMTP = None
 
diff --git a/test/test_config.py b/test/test_config.py
index 584579d..36e8bd8 100644
--- a/test/test_config.py
+++ b/test/test_config.py
@@ -306,7 +306,7 @@ def test_config_notification_setup():
         }
     )
 
-    with pytest.raises(ConfigError, match="`use_ssl` must be set to either `true` or `false`"):
+    with pytest.raises(ConfigError, match="Config error: `use_ssl` must be set to either `true` or `false`"):
         validate_config(config)
 
     # int variable test
@@ -326,7 +326,7 @@ def test_config_notification_setup():
         }
     )
 
-    with pytest.raises(ConfigError, match="`smtp_port` must be set an integer"):
+    with pytest.raises(ConfigError, match="Config error: `smtp_port` must be set an integer"):
         validate_config(config)
     # complete setting but does not work
     config.update(

From 20ee1b8968b60d7bccd20956ab65b07cacddcaeb Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 10:54:06 +0200
Subject: [PATCH 18/32] add minimal email interval

---
 config.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/config.py b/config.py
index 5304d20..0b2412b 100644
--- a/config.py
+++ b/config.py
@@ -131,6 +131,9 @@ def validate_config(config):
             if not isinstance(config.notification.smtp_port, int):
                 raise ConfigError("Config error: `smtp_port` must be set an integer.")
 
+        if "minimal_email_interval" in config.notification:
+            if not isinstance(config.notification.minimal_email_interval, (int, float)):
+                raise ConfigError("Config error: `minimal_email_interval` must be set a number.")
 
         smtp_conn: smtplib.SMTP = None
 

From 0b3c50539e928d1ff075130d35d33f441327a76c Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Wed, 26 Jul 2023 11:15:54 +0200
Subject: [PATCH 19/32] add time difference between emails

---
 dbsync_daemon.py  |  8 +++++---
 smtp_functions.py | 43 ++++++++++++++++++++++++++++---------------
 2 files changed, 33 insertions(+), 18 deletions(-)

diff --git a/dbsync_daemon.py b/dbsync_daemon.py
index aad699e..c7d51e4 100644
--- a/dbsync_daemon.py
+++ b/dbsync_daemon.py
@@ -159,6 +159,8 @@ def main():
             except dbsync.DbSyncError as e:
                 handle_error_and_exit(e)
 
+        last_email_send = None
+
         while True:
             print(datetime.datetime.now())
 
@@ -176,9 +178,9 @@ def main():
 
             except dbsync.DbSyncError as e:
                 logging.error(str(e))
-                if can_send_email(config) and error_msg != str(e):
-                    send_email(str(e), config)
-                    error_msg = str(e)
+                if can_send_email(config):
+                    send_email(str(e), last_email_send, config)
+                    last_email_send = datetime.datetime.now()
 
             logging.debug("Going to sleep")
             time.sleep(sleep_time)
diff --git a/smtp_functions.py b/smtp_functions.py
index 967605d..42971c8 100644
--- a/smtp_functions.py
+++ b/smtp_functions.py
@@ -27,28 +27,41 @@ def log_smtp_user(host: typing.Union[smtplib.SMTP_SSL, smtplib.SMTP], config: Dy
         host.login(config.notification.smtp_username, config.notification.smtp_password)
 
 
-def send_email(error: str, config: Dynaconf) -> None:
-    smtp_conn = create_connection(config)
+def should_send_another_email(
+    current_time: datetime.datetime, last_email_send: typing.Optional[datetime.datetime], config: Dynaconf
+) -> bool:
+    if last_email_send is None:
+        return True
+    min_time_diff = config.notification.minimal_email_interval if "minimal_email_interval" in config.notification else 4
+    time_diff = current_time - last_email_send
+    return time_diff.seconds > (min_time_diff * 3600)
+
+
+def send_email(error: str, last_email_send: typing.Optional[datetime.datetime], config: Dynaconf) -> None:
+    current_time = datetime.datetime.now()
+
+    if should_send_another_email(current_time, last_email_send, config):
+        smtp_conn = create_connection(config)
 
-    log_smtp_user(smtp_conn, config)
+        log_smtp_user(smtp_conn, config)
 
-    msg = EmailMessage()
-    msg["Subject"] = config.notification.email_subject
-    msg["From"] = config.notification.email_sender
-    msg["To"] = ", ".join(config.notification.email_recipients)
+        msg = EmailMessage()
+        msg["Subject"] = config.notification.email_subject
+        msg["From"] = config.notification.email_sender
+        msg["To"] = ", ".join(config.notification.email_recipients)
 
-    date_time = datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S")
+        date_time = datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S")
 
-    error = f"{date_time}: {error}"
+        error = f"{date_time}: {error}"
 
-    msg.set_content(error)
+        msg.set_content(error)
 
-    sender_email = config.notification.email_sender
-    if "smtp_username" in config.notification:
-        sender_email = config.notification.smtp_username
+        sender_email = config.notification.email_sender
+        if "smtp_username" in config.notification:
+            sender_email = config.notification.smtp_username
 
-    smtp_conn.sendmail(sender_email, config.notification.email_recipients, msg.as_string())
-    smtp_conn.quit()
+        smtp_conn.sendmail(sender_email, config.notification.email_recipients, msg.as_string())
+        smtp_conn.quit()
 
 
 def can_send_email(config: Dynaconf) -> bool:

From 712860cfb0681a0163f8e0277faf1eb905f8c896 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@outlook.com>
Date: Fri, 4 Aug 2023 14:53:22 +0200
Subject: [PATCH 20/32] fix message

Co-authored-by: Martin Dobias <wonder.sk@gmail.com>
---
 config.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.py b/config.py
index 0b2412b..922af73 100644
--- a/config.py
+++ b/config.py
@@ -129,7 +129,7 @@ def validate_config(config):
 
         if "smtp_port" in config.notification:
             if not isinstance(config.notification.smtp_port, int):
-                raise ConfigError("Config error: `smtp_port` must be set an integer.")
+                raise ConfigError("Config error: `smtp_port` must be set to an integer.")
 
         if "minimal_email_interval" in config.notification:
             if not isinstance(config.notification.minimal_email_interval, (int, float)):

From 9a6f026a36cf217c46e53a9f05b04fdd9025bdfb Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@outlook.com>
Date: Fri, 4 Aug 2023 14:53:36 +0200
Subject: [PATCH 21/32] fix message

Co-authored-by: Martin Dobias <wonder.sk@gmail.com>
---
 config.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.py b/config.py
index 922af73..4b0b8e0 100644
--- a/config.py
+++ b/config.py
@@ -117,7 +117,7 @@ def validate_config(config):
                 raise ConfigError(f"Config error: `{setting}` is missing from `notification`.")
 
         if not isinstance(config.notification.email_recipients, list):
-            raise ConfigError("Config error: `email_recipients` should be list of addresses.")
+            raise ConfigError("Config error: `email_recipients` should be a list of addresses.")
 
         if "use_ssl" in config.notification:
             if not isinstance(config.notification.use_ssl, bool):

From c8b1d3a768a3f207ac5a2e2faebca135ccb64d9c Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@outlook.com>
Date: Fri, 4 Aug 2023 14:54:01 +0200
Subject: [PATCH 22/32] fix message

Co-authored-by: Martin Dobias <wonder.sk@gmail.com>
---
 config.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.py b/config.py
index 4b0b8e0..0835557 100644
--- a/config.py
+++ b/config.py
@@ -133,7 +133,7 @@ def validate_config(config):
 
         if "minimal_email_interval" in config.notification:
             if not isinstance(config.notification.minimal_email_interval, (int, float)):
-                raise ConfigError("Config error: `minimal_email_interval` must be set a number.")
+                raise ConfigError("Config error: `minimal_email_interval` must be set to a number.")
 
         smtp_conn: smtplib.SMTP = None
 

From a289efafa0b80ec3051a2491fa266a4530afc130 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 14:31:45 +0200
Subject: [PATCH 23/32] zero port

---
 smtp_functions.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/smtp_functions.py b/smtp_functions.py
index 42971c8..73a6e86 100644
--- a/smtp_functions.py
+++ b/smtp_functions.py
@@ -10,7 +10,7 @@ def create_connection(config: Dynaconf) -> typing.Union[smtplib.SMTP_SSL, smtpli
     if "smtp_port" in config.notification:
         port = config.notification.smtp_port
     else:
-        port = smtplib.SMTP_PORT
+        port = 0
 
     if "use_ssl" in config.notification and config.notification.use_ssl:
         host = smtplib.SMTP_SSL(config.notification.smtp_server, port)

From 9192e9ac20d20c18ee18f41b4ca1ee9114cb7e6c Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 14:31:57 +0200
Subject: [PATCH 24/32] fix typo in variable

---
 smtp_functions.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/smtp_functions.py b/smtp_functions.py
index 73a6e86..fec84ee 100644
--- a/smtp_functions.py
+++ b/smtp_functions.py
@@ -28,12 +28,12 @@ def log_smtp_user(host: typing.Union[smtplib.SMTP_SSL, smtplib.SMTP], config: Dy
 
 
 def should_send_another_email(
-    current_time: datetime.datetime, last_email_send: typing.Optional[datetime.datetime], config: Dynaconf
+    current_time: datetime.datetime, last_email_sent: typing.Optional[datetime.datetime], config: Dynaconf
 ) -> bool:
-    if last_email_send is None:
+    if last_email_sent is None:
         return True
     min_time_diff = config.notification.minimal_email_interval if "minimal_email_interval" in config.notification else 4
-    time_diff = current_time - last_email_send
+    time_diff = current_time - last_email_sent
     return time_diff.seconds > (min_time_diff * 3600)
 
 

From 7bb5759afb8a70b4a86bd4650160f418c69baf83 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 14:52:52 +0200
Subject: [PATCH 25/32] catch errors and simplify into single function

---
 config.py           | 21 ++++++++-------------
 smtp_functions.py   | 12 ++++--------
 test/test_config.py |  2 +-
 3 files changed, 13 insertions(+), 22 deletions(-)

diff --git a/config.py b/config.py
index 0835557..0c0c59d 100644
--- a/config.py
+++ b/config.py
@@ -16,7 +16,7 @@
 import smtplib
 import socket
 
-from smtp_functions import create_connection, log_smtp_user
+from smtp_functions import create_connection_and_log_user
 
 config = Dynaconf(
     envvar_prefix=False,
@@ -135,19 +135,14 @@ def validate_config(config):
             if not isinstance(config.notification.minimal_email_interval, (int, float)):
                 raise ConfigError("Config error: `minimal_email_interval` must be set to a number.")
 
-        smtp_conn: smtplib.SMTP = None
-
-        try:
-            smtp_conn = create_connection(config)
-        except OSError:
-            raise ConfigError(f"Config error: Cannot connect to SMTP server: `{config.notification.smtp_server}`.")
-
         try:
-            log_smtp_user(smtp_conn, config)
-        except smtplib.SMTPAuthenticationError as e:
-            raise ConfigError(f"Config SMTP Error: {str(e.smtp_error)}.")
-
-        smtp_conn.quit()
+            smtp_conn = create_connection_and_log_user(config)
+            smtp_conn.quit()
+        except (OSError, smtplib.SMTPConnectError, smtplib.SMTPAuthenticationError) as e:
+            err = str(e)
+            if isinstance(e, (smtplib.SMTPConnectError, smtplib.SMTPAuthenticationError)):
+                err = str(e.smtp_error)
+            raise ConfigError(f"Config SMTP Error: {err}.")
 
 
 def get_ignored_tables(
diff --git a/smtp_functions.py b/smtp_functions.py
index fec84ee..5f4e481 100644
--- a/smtp_functions.py
+++ b/smtp_functions.py
@@ -6,7 +6,7 @@
 from dynaconf import Dynaconf
 
 
-def create_connection(config: Dynaconf) -> typing.Union[smtplib.SMTP_SSL, smtplib.SMTP]:
+def create_connection_and_log_user(config: Dynaconf) -> typing.Union[smtplib.SMTP_SSL, smtplib.SMTP]:
     if "smtp_port" in config.notification:
         port = config.notification.smtp_port
     else:
@@ -17,15 +17,13 @@ def create_connection(config: Dynaconf) -> typing.Union[smtplib.SMTP_SSL, smtpli
     else:
         host = smtplib.SMTP(config.notification.smtp_server, port)
 
-    return host
-
-
-def log_smtp_user(host: typing.Union[smtplib.SMTP_SSL, smtplib.SMTP], config: Dynaconf) -> None:
     if "use_tls" in config.notification and config.notification.use_tls:
         host.starttls()
     if config.notification.smtp_username and config.notification.smtp_password:
         host.login(config.notification.smtp_username, config.notification.smtp_password)
 
+    return host
+
 
 def should_send_another_email(
     current_time: datetime.datetime, last_email_sent: typing.Optional[datetime.datetime], config: Dynaconf
@@ -41,9 +39,7 @@ def send_email(error: str, last_email_send: typing.Optional[datetime.datetime],
     current_time = datetime.datetime.now()
 
     if should_send_another_email(current_time, last_email_send, config):
-        smtp_conn = create_connection(config)
-
-        log_smtp_user(smtp_conn, config)
+        smtp_conn = create_connection_and_log_user(config)
 
         msg = EmailMessage()
         msg["Subject"] = config.notification.email_subject
diff --git a/test/test_config.py b/test/test_config.py
index 36e8bd8..cd6458c 100644
--- a/test/test_config.py
+++ b/test/test_config.py
@@ -345,7 +345,7 @@ def test_config_notification_setup():
         }
     )
 
-    with pytest.raises(ConfigError, match="Config error: Cannot connect to SMTP server"):
+    with pytest.raises(ConfigError, match="Config SMTP Error"):
         validate_config(config)
 
     # notifications are set, emails can be send - but this config was not validated, as it would be in real run

From 18d1a3afc7da42212b1a9136becdea9066460a1c Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 14:53:04 +0200
Subject: [PATCH 26/32] fix typo

---
 dbsync_daemon.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dbsync_daemon.py b/dbsync_daemon.py
index c7d51e4..81111f8 100644
--- a/dbsync_daemon.py
+++ b/dbsync_daemon.py
@@ -120,7 +120,7 @@ def main():
 
     if args.test_notification_email:
         send_email("Mergin DB Sync test email.", config)
-        logging.debug("Email send!")
+        logging.debug("Email sent!")
         sys.exit(0)
 
     if args.force_init and args.skip_init:

From 18c22a371d11f26b20fb2e165bbbbf8a904195eb Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 14:57:34 +0200
Subject: [PATCH 27/32] add docstrings

---
 smtp_functions.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/smtp_functions.py b/smtp_functions.py
index 5f4e481..e5ab97f 100644
--- a/smtp_functions.py
+++ b/smtp_functions.py
@@ -7,6 +7,7 @@
 
 
 def create_connection_and_log_user(config: Dynaconf) -> typing.Union[smtplib.SMTP_SSL, smtplib.SMTP]:
+    """Create connection and log user to the SMTP server using the configuration in config."""
     if "smtp_port" in config.notification:
         port = config.notification.smtp_port
     else:
@@ -28,6 +29,8 @@ def create_connection_and_log_user(config: Dynaconf) -> typing.Union[smtplib.SMT
 def should_send_another_email(
     current_time: datetime.datetime, last_email_sent: typing.Optional[datetime.datetime], config: Dynaconf
 ) -> bool:
+    """Checks if another email should be sent. The time difference to last sent email needs to larger them
+    minimal interval specified in config or 4 hours if no value was specified."""
     if last_email_sent is None:
         return True
     min_time_diff = config.notification.minimal_email_interval if "minimal_email_interval" in config.notification else 4
@@ -36,6 +39,7 @@ def should_send_another_email(
 
 
 def send_email(error: str, last_email_send: typing.Optional[datetime.datetime], config: Dynaconf) -> None:
+    """Sends email with provided error using the settings in config."""
     current_time = datetime.datetime.now()
 
     if should_send_another_email(current_time, last_email_send, config):
@@ -61,6 +65,7 @@ def send_email(error: str, last_email_send: typing.Optional[datetime.datetime],
 
 
 def can_send_email(config: Dynaconf) -> bool:
+    """Checks if notification settings is in the config and emails can be send."""
     if "notification" in config:
         return True
     return False

From 3d997ab09a3e553670339e5b7acc24f0b7f63e57 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 14:59:57 +0200
Subject: [PATCH 28/32] email sending should fail without crashing the deamon

---
 smtp_functions.py | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/smtp_functions.py b/smtp_functions.py
index e5ab97f..78df4be 100644
--- a/smtp_functions.py
+++ b/smtp_functions.py
@@ -43,8 +43,6 @@ def send_email(error: str, last_email_send: typing.Optional[datetime.datetime],
     current_time = datetime.datetime.now()
 
     if should_send_another_email(current_time, last_email_send, config):
-        smtp_conn = create_connection_and_log_user(config)
-
         msg = EmailMessage()
         msg["Subject"] = config.notification.email_subject
         msg["From"] = config.notification.email_sender
@@ -60,8 +58,12 @@ def send_email(error: str, last_email_send: typing.Optional[datetime.datetime],
         if "smtp_username" in config.notification:
             sender_email = config.notification.smtp_username
 
-        smtp_conn.sendmail(sender_email, config.notification.email_recipients, msg.as_string())
-        smtp_conn.quit()
+        try:
+            smtp_conn = create_connection_and_log_user(config)
+            smtp_conn.sendmail(sender_email, config.notification.email_recipients, msg.as_string())
+            smtp_conn.quit()
+        except:
+            pass
 
 
 def can_send_email(config: Dynaconf) -> bool:

From 63716b387410b0e9bda4546fc083297d97e303ba Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 15:00:09 +0200
Subject: [PATCH 29/32] restyle imports

---
 config.py | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/config.py b/config.py
index 0c0c59d..1a62cc0 100644
--- a/config.py
+++ b/config.py
@@ -6,15 +6,14 @@
 License: MIT
 """
 
-from dynaconf import (
-    Dynaconf,
-)
-import platform
-import tempfile
 import pathlib
-import subprocess
+import platform
 import smtplib
 import socket
+import subprocess
+import tempfile
+
+from dynaconf import Dynaconf
 
 from smtp_functions import create_connection_and_log_user
 

From e64ef030013cb63a0aee9fa9addaff6dd8fe4795 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 15:14:41 +0200
Subject: [PATCH 30/32] notification description in use.md

---
 config.yaml.default | 15 ---------------
 docs/using.md       | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/config.yaml.default b/config.yaml.default
index 1d7035f..1d5f03b 100644
--- a/config.yaml.default
+++ b/config.yaml.default
@@ -29,18 +29,3 @@ connections:
 daemon:
   # How often to synchronize (in seconds)
   sleep_time: 10
-
-# optional setting, if you do not want notifications on sync errors to be send via email just delete this section
-notification:
-  # address of stmp server to send emails
-  smtp_server: "xxx.xxx"
-  # smtp server user
-  smtp_username: "user@email.xxx"
-  # smtp user's password
-  smtp_password: "password"
-  # email sender to be displayed in the message
-  email_sender: "dbsync@info.com"
-  # email subject
-  email_subject: "DB Sync Error"
-  # list of recipients of the email notification
-  email_recipients: ["recipient1@email.xxx", "recipient1@email.xxx"]
\ No newline at end of file
diff --git a/docs/using.md b/docs/using.md
index 2edda0a..616cd1e 100644
--- a/docs/using.md
+++ b/docs/using.md
@@ -76,6 +76,7 @@ daemon:
 
 - `--log-verbosity` use `errors` or `messages` to specify what should be logged. Default is `messages`.
 
+- `--test-notification-email` used to test send notification email (see below for details about sending emails in case of sync fails)
 
 ## Excluding tables from sync
 
@@ -93,3 +94,36 @@ connections:
       - table1
       - table2
 ```
+
+## Sending emails in case of synchronization fail
+
+User can be notified about sync fails via email by including `notification` with proper setting in the config file
+
+The command line option `--test-notification-email` can be used to only send the notification email without running the daemon. This should be useful to test the `notification` settings setup.
+
+```yaml
+# optional setting, if you do not want notifications on sync errors to be send via email just delete this section
+notification:
+  # first four options are required to be present 
+  # address of stmp server to send emails
+  smtp_server: "xxx.xxx"
+   # email sender to be displayed in the message
+  email_sender: "dbsync@info.com"
+  # email subject
+  email_subject: "DB Sync Error"
+  # list of recipients of the email notification
+  email_recipients: ["recipient1@email.xxx", "recipient1@email.xxx"]
+  # the following configuration is optional and does not need to be specified
+  # smtp server user
+  smtp_username: "user@email.xxx"
+  # smtp user's password
+  smtp_password: "password"
+  # smtp port
+  smtp_port: 25
+  # use ssl true/false
+  use_ssl: false
+  # use tls true/false
+  use_tls: false
+  # minimal interval for sending emails in hours (default value is 4) to avoid sending too many emails
+  minimal_email_interval: 4
+```

From 873bfaff17ef510ed3208f0d31423ca570e3dd99 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 15:15:22 +0200
Subject: [PATCH 31/32] drop unused imports

---
 log_functions.py | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/log_functions.py b/log_functions.py
index bbe657b..40125d7 100644
--- a/log_functions.py
+++ b/log_functions.py
@@ -3,10 +3,6 @@
 import sys
 import typing
 
-from dynaconf import Dynaconf
-
-from config import config
-
 
 def filter_below_error(record):
     """Only lets through log messages with log level below ERROR ."""

From c4ab2720e5e8d61f8c07f0a14d211afa061cab68 Mon Sep 17 00:00:00 2001
From: Jan Caha <jan.caha@lutraconsulting.co.uk>
Date: Fri, 4 Aug 2023 15:16:09 +0200
Subject: [PATCH 32/32] drop unused import

---
 config.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/config.py b/config.py
index 1a62cc0..e2380cc 100644
--- a/config.py
+++ b/config.py
@@ -9,7 +9,6 @@
 import pathlib
 import platform
 import smtplib
-import socket
 import subprocess
 import tempfile