Add README.md

README.md

@@ -0,0 +1,52 @@
+[Prometheus](https://prometheus.io/) endpoint to report the healthcheck status of Docker containers.
+
+# Usage
+```
+usage: dockstat.py [-h] [-H]
+
+optional arguments:
+  -h, --help         show this help message and exit
+  -H, --healthcheck  Simply exit with 0 for healthy or 1 when unhealthy
+```
+
+# Example
+```
+curl -qsS localhost:8080/metrics
+# HELP container_inspect_state_health_status Container's healthcheck value (binary)
+# TYPE container_inspect_state_health_status gauge
+container_inspect_state_health_status{id="21ac232f35edc4e630ed0c6b19b828a40df3dbc280c6bcf779b02a1488a741c3",name="alertify",value="healthy"} 1.0
+container_inspect_state_health_status{id="73a3d19d996de90f15da6cea016d2b1733d0e63bca4d36b0a1bcb2d680d6f108",name="dockstat",value="healthy"} 1.0
+container_inspect_state_health_status{id="db14abb41eec0ff06dc11b740b71839aec2b3855192b83a4ba31ee77bd21abfd",name="gotify",value="healthy"} 1.0
+container_inspect_state_health_status{id="470e17a15751881cc0787f9aab6f1af000b7bbce7e590d82de987c583425b4ef",name="down-example",value="unhealthy"} 0.0
+```
+
+# Notes
+* Requires access to the Docker socket (`/var/run/docker.sock`)
+
+# Docker
+## Build
+```bash
+docker build . -t 'dockstat:latest'
+```
+
+## Run
+```bash
+docker run --name dockstat -p 8080:8080 -v /var/run/docker.sock:/var/run/docker.sock:ro -e TZ=Europe/London dockstat:latest
+```
+
+## Compose
+```yaml
+---
+version: "2"
+services:
+  dockstat:
+    image: dockstat:latest
+    container_name: dockstat
+    environment:
+      - TZ=Europe/London
+    ports:
+      - "8080:8080"
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+    restart: unless-stopped
+```

dockstat.py

@@ -64,7 +64,8 @@ class HTTPHandler(MetricsHandler):
         """
         Method to handle the request for metrics
         """
-        self._healthcheck(message=False)
+        if not self._healthcheck(message=False):
+            return
 
         registry = CollectorRegistry()