Add Healthchecks (#611)

* Add Apprise

* 💄 Formatted

* ✨ Add health checks

* ✅

* 🐛 Added Default value

public/v4/apps/healthchecks.yml

@@ -0,0 +1,56 @@
+captainVersion: 4
+services:
+    # HealthChecks
+    $$cap_appname:
+        image: healthchecks/healthchecks:$$cap_hc_version
+        restart: always
+        environment:
+            DB: postgres
+            DB_HOST: srv-captain--$$cap_appname-db
+            DB_NAME: hc
+            DB_PASSWORD: $$cap_postgres_password
+            DB_PORT: 5432
+            DB_SSLMODE: prefer
+            DB_TARGET_SESSION_ATTRS: read-write
+            DB_USER: postgres
+            DEBUG: False
+            SECRET_KEY: $$cap_gen_random_hex(64)
+            SITE_ROOT: http://0.0.0.0:8000
+        caproverExtra:
+            containerHttpPort: '8000'
+    # Postgres
+    $$cap_appname-db:
+        image: postgres:12
+        volumes:
+            - $$cap_appname-db-data:/var/lib/postgresql/data
+        restart: always
+        environment:
+            POSTGRES_USER: postgres
+            POSTGRES_PASSWORD: $$cap_postgres_password
+            POSTGRES_DB: hc
+        caproverExtra:
+            notExposeAsWebApp: 'true'
+caproverOneClickApp:
+    variables:
+        - id: $$cap_hc_version
+          label: hc Manifest digest
+          defaultValue: 'v1.25.0'
+          description: Find on https://hub.docker.com/r/healthchecks/healthchecks/tags
+        - id: $$cap__postgres_password
+          label: Postgres Password
+          description: Password must be at least 12 characters.  Please use a random string.
+          defaultValue: $$cap_gen_random_hex(16)
+          validRegex: /^[^\@]{12,}$/
+    instructions:
+        start: |-
+            Healthchecks is a cron job monitoring service. It listens for HTTP requests and email messages ("pings") from your cron jobs and scheduled tasks ("checks"). When a ping does not arrive on time, Healthchecks sends out alerts.
+            Github: https://github.com/healthchecks/healthchecks
+
+        end: |-
+            Aaaand you're done! 😄
+            Your service is available at http://$$cap_appname.$$cap_root_domain
+            More environment variables can be found at https://github.com/healthchecks/healthchecks/blob/master/docker/.env
+    displayName: 'HealthChecks'
+    isOfficial: true
+    description: Healthchecks is a cron job monitoring service.
+    documentation: https://github.com/healthchecks/healthchecks