Watchtower: Add notification template

coreos-config/roles/compose_project/templates/watchtower/docker-compose.yaml

@@ -10,6 +10,35 @@ services:
       WATCHTOWER_CLEANUP: 1
       WATCHTOWER_ROLLING_RESTART: 1
       WATCHTOWER_NOTIFICATION_URL: "matrix://{{ watchtower.matrix.user }}:{{ watchtower.matrix.password }}@pantalaimon:8008/?disableTLS=yes{% if watchtower.matrix.options is defined %}&{{ watchtower.matrix.options | join('&') }}{% endif%}"
+      WATCHTOWER_NOTIFICATION_REPORT: "true"
+      WATCHTOWER_NOTIFICATION_TEMPLATE: |
+        {% raw %}
+        {{- if .Report -}}
+          {{- with .Report -}}
+        {{- if ( or .Updated .Failed ) -}}
+        {% endraw %}
+        Updates on {{ inventory_hostname }}{% raw %}
+        {{len .Scanned}} Scanned, {{len .Updated}} Updated, {{len .Failed}} Failed
+              {{- range .Updated}}
+        - {{.Name}} ({{.ImageName}}): {{.CurrentImageID.ShortID}} updated to {{.LatestImageID.ShortID}}
+              {{- end -}}
+              {{- range .Fresh}}
+        - {{.Name}} ({{.ImageName}}): {{.State}}
+            {{- end -}}
+            {{- range .Skipped}}
+        - {{.Name}} ({{.ImageName}}): {{.State}}: {{.Error}}
+            {{- end -}}
+            {{- range .Failed}}
+        - {{.Name}} ({{.ImageName}}): {{.State}}: {{.Error}}
+            {{- end -}}
+          {{- end -}}
+          {{- end -}}
+        {{- else -}}
+          {% endraw %}
+        Updates on {{ inventory_hostname }}{% raw %}
+        {{range .Entries -}}{{.Message}}{{"\n"}}{{- end -}}
+        {{- end -}}{% endraw %}
+
     volumes:
       - /var/run/docker.sock:/var/run/docker.sock
       - /home/core/.docker:/config