Notification error log handler (#403)

* Add a notifications debug/error log interface (Link available under the notification URLs list)

changedetectionio/__init__.py

@@ -70,6 +70,7 @@ app.config['LOGIN_DISABLED'] = False
 # Disables caching of the templates
 app.config['TEMPLATES_AUTO_RELOAD'] = True
 
+notification_debug_log=[]
 
 def init_app_secret(datastore_path):
     secret = ""
@@ -529,6 +530,7 @@ def changedetection_app(config=None, datastore_o=None):
                                 'notification_title': form.notification_title.data,
                                 'notification_body': form.notification_body.data,
                                 'notification_format': form.notification_format.data,
+                                'uuid': uuid
                                 }
                     notification_q.put(n_object)
                     flash('Test notification queued.')
@@ -765,6 +767,14 @@ def changedetection_app(config=None, datastore_o=None):
                                  uuid=uuid)
         return output
 
+    @app.route("/settings/notification-logs", methods=['GET'])
+    @login_required
+    def notification_logs():
+        global notification_debug_log
+        output = render_template("notification-log.html",
+                                 logs=notification_debug_log if len(notification_debug_log) else ["No errors or warnings detected"])
+
+        return output
     @app.route("/api/<string:uuid>/snapshot/current", methods=['GET'])
     @login_required
     def api_snapshot(uuid):
@@ -997,6 +1007,7 @@ def check_for_new_version():
         app.config.exit.wait(86400)
 
 def notification_runner():
+    global notification_debug_log
     while not app.config.exit.is_set():
         try:
             # At the moment only one thread runs (single runner)
@@ -1011,8 +1022,18 @@ def notification_runner():
                 notification.process_notification(n_object, datastore)
 
             except Exception as e:
-                print("Watch URL: {}  Error {}".format(n_object['watch_url'], e))
-                datastore.update_watch(uuid=n_object['uuid'], update_obj={'last_error': "Notification error: " + str(e)})
+                print("Watch URL: {}  Error {}".format(n_object['watch_url'], str(e)))
+
+                # UUID wont be present when we submit a 'test' from the global settings
+                if 'uuid' in n_object:
+                    datastore.update_watch(uuid=n_object['uuid'], update_obj={'last_error': "Notification error detected, please see logs."})
+
+                log_lines = str(e).splitlines()
+                notification_debug_log += log_lines
+
+                # Trim the log length
+                notification_debug_log = notification_debug_log[-100:]
+
 
 
 # Thread runner to check every minute, look for new watches to feed into the Queue.

changedetectionio/notification.py

@@ -25,9 +25,7 @@ default_notification_body = '{watch_url} had a change.\n---\n{diff}\n---\n'
 default_notification_title = 'ChangeDetection.io Notification - {watch_url}'
 
 def process_notification(n_object, datastore):
-    import logging
-    log = logging.getLogger('apprise')
-    log.setLevel('TRACE')
+
     apobj = apprise.Apprise(debug=True)
 
     for url in n_object['notification_urls']:
@@ -53,11 +51,22 @@ def process_notification(n_object, datastore):
         n_title = n_title.replace(token, val)
         n_body = n_body.replace(token, val)
 
-    apobj.notify(
+    # https://github.com/caronc/apprise/wiki/Development_LogCapture
+    # Anything higher than or equal to WARNING (which covers things like Connection errors)
+    # raise it as an exception
+
+    with apprise.LogCapture(level=apprise.logging.DEBUG) as logs:
+        apobj.notify(
         body=n_body,
         title=n_title,
-        body_format=n_format,
-    )
+        body_format=n_format)
+
+        # Returns empty string if nothing found, multi-line string otherwise
+        log_value = logs.getvalue()
+        if log_value and 'WARNING' in log_value or 'ERROR' in log_value:
+            raise Exception(log_value)
+
+
 
 # Notification title + body content parameters get created here.
 def create_notification_parameters(n_object, datastore):

changedetectionio/templates/_common_fields.jinja

@@ -15,6 +15,7 @@
                                 <li>Use <a target=_new href="https://github.com/caronc/apprise">AppRise URLs</a> for notification to just about any service! <i><a target=_new href="https://github.com/dgtlmoon/changedetection.io/wiki/Notification-configuration-notes">Please read the notification services wiki here for important configuration notes</a></i>.</li>
                                 <li><code>discord://</code> will silently fail if the total message length is more than 2000 chars.</li>
                                 <li><code>tgram://</code> bots cant send messages to other bots, so you should specify chat ID of non-bot user.</li>
+                                <li>Go here for <a href="{{url_for('notification_logs')}}">Notification debug logs</a></li>
                               </ul>
                             </div>
                         </div>

changedetectionio/templates/notification-log.html

@@ -0,0 +1,19 @@
+{% extends 'base.html' %}
+
+{% block content %}
+<div class="edit-form">
+     <div class="inner">
+
+         <h4 style="margin-top: 0px;">The following issues were detected when sending notifications</h4>
+                <div id="notification-customisation">
+                <ul style="font-size: 80%; margin:0px; padding: 0 0 0 7px">
+                {% for log in logs|reverse %}
+                    <li>{{log}}</li>
+                {% endfor %}
+                </ul>
+                </div>
+
+     </div>
+</div>
+
+{% endblock %}

changedetectionio/templates/settings.html

@@ -59,6 +59,8 @@
                         {{ render_common_settings_form(form, current_base_url) }}
                     </div>
                 </fieldset>
+                <a href="{{url_for('notification_logs')}}">Notification debug logs</a>
+
             </div>
 
             <div class="tab-pane-inner" id="fetching">

changedetectionio/tests/test_notification.py

@@ -226,3 +226,32 @@ def test_check_notification(client, live_server):
     )
     assert b"Notification Body and Title is required when a Notification URL is used" in res.data
 
+
+    # Check we capture the failure, we can just use trigger_check = y here
+    res = client.post(
+        url_for("edit_page", uuid="first"),
+        data={"notification_urls": "jsons://broken-url.changedetection.io/test",
+              "notification_title": "xxx",
+              "notification_body": "xxxxx",
+              "notification_format": "Text",
+              "url": test_url,
+              "tag": "my tag",
+              "title": "my title",
+              "headers": "",
+              "fetch_backend": "html_requests",
+              "trigger_check": "y"},
+        follow_redirects=True
+    )
+
+    time.sleep(3)
+
+    # The error should show in the notification logs
+    res = client.get(
+        url_for("notification_logs"))
+    assert bytes("Name or service not known".encode('utf-8')) in res.data
+
+    # And it should be listed on the watch overview
+    res = client.get(
+        url_for("index"))
+    assert bytes("Notification error detected".encode('utf-8')) in res.data
+