Add workflow to build and test docker image

ci/check_api_endpoint.py

@@ -0,0 +1,40 @@
+"""
+Test that the root API endpoint is available.
+"""
+
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+import json
+import requests
+
+# We expect the server to be running on the local host
+url = "http://localhost:8000/api/"
+
+print("Testing InvenTree API endpoint")
+
+response = requests.get(url)
+
+assert(response.status_code == 200)
+
+print("- Response 200 OK")
+
+data = json.loads(response.text)
+
+required_keys = [
+    'server',
+    'version',
+    'apiVersion',
+    'worker_running',
+]
+
+for key in required_keys:
+    assert(key in data)
+    print(f"- Found key '{key}'")
+
+# Check that the worker is running
+assert(data['worker_running'])
+
+print("- Background worker is operational")
+
+print("API Endpoint Tests Passed OK")