feat: implemented readyz probe

Author: bourbonbourbon

app.py

@@ -4,7 +4,6 @@
 import io
 import json
 import ast
-import datetime
 from http import HTTPStatus
 import minio
 import valkey
@@ -44,6 +43,8 @@
 
 valkey_client = valkey.Valkey(host=config["VKURL"], port=config["VKPORT"], db=0)
 
+SENSEBOX_FAIL_COUNT = 0
+
 
 @app.route(rule="/metrics")
 def metrics():
@@ -56,21 +57,11 @@ def print_version():
     return jsonify({"version": __version__}), 200
 
 
-@app.route(rule="/temperature")
-def temperature():
-    v_value = valkey_client.get(name="avg-temp")
-    if v_value is not None:
-        v_value = json.loads(
-            s=json.dumps(
-                obj=ast.literal_eval(node_or_string=v_value.decode(encoding="UTF-8"))
-            )
-        )
-        if v_value.get("status") == "Internal Error":
-            return jsonify(v_value), HTTPStatus.INTERNAL_SERVER_ERROR
-        else:
-            return jsonify(v_value), HTTPStatus.OK
+def query_main_and_store():
     api = OpenSenseMap(base_url=BASE_URL)
-    data, return_code = api.get_avg_temperature(sense_boxes=senseBoxes)
+    data, return_code, fail_count = api.get_avg_temperature(sense_boxes=senseBoxes)
+    global SENSEBOX_FAIL_COUNT
+    SENSEBOX_FAIL_COUNT = fail_count
 
     data_as_bytes = str(object=data).encode(encoding="UTF-8")
     data_to_minio_stream = io.BytesIO(initial_bytes=data_as_bytes)
@@ -82,26 +73,54 @@ def temperature():
     )
 
     valkey_client.set(name="avg-temp", value=str(object=data), ex=3000)
+    return jsonify(data), return_code
+
+
+@app.route(rule="/temperature")
+def temperature():
+    v_value = valkey_client.get(name="avg-temp")
+    if v_value is not None:
+        v_value = json.loads(
+            s=json.dumps(
+                obj=ast.literal_eval(node_or_string=v_value.decode(encoding="UTF-8"))
+            )
+        )
+        if v_value.get("status") == "Internal Error":
+            return jsonify(v_value), HTTPStatus.INTERNAL_SERVER_ERROR
+        return jsonify(v_value), HTTPStatus.OK
 
     total_temp_requests.inc()
-    return jsonify(data), return_code
+    return query_main_and_store()
 
 
 @app.route(rule="/store")
 def store():
+    query_main_and_store()
     total_store_requests.inc()
     return temperature()
 
 
 @app.route(rule="/readyz")
 def readyz():
-    # prometheus
-    pass
+    most_sense_boxes_working = SENSEBOX_FAIL_COUNT < (len(senseBoxes) // 2) + 1
+    v_value = valkey_client.get(name="avg-temp")
+    v_ttl = valkey_client.ttl(name="avg-temp")
+
+    if most_sense_boxes_working and v_value is not None and v_ttl > 1:
+        return str(SENSEBOX_FAIL_COUNT), HTTPStatus.OK
+    return str(SENSEBOX_FAIL_COUNT), HTTPStatus.INTERNAL_SERVER_ERROR
+
+
+# Hacky way to populate cache, s3 and senseBox_fail_count
+@app.before_request
+def first_temp_query():
+    app.before_request_funcs[None].remove(first_temp_query)
+    temperature()
 
 
 if __name__ == "__main__":
-    bucket_found = minio_client.bucket_exists(bucket_name=bucket_name)
-    if not bucket_found:
+    BUCKET_FOUND = minio_client.bucket_exists(bucket_name=bucket_name)
+    if not BUCKET_FOUND:
         minio_client.make_bucket(bucket_name=bucket_name)
 
     from waitress import serve

services/opensensemap.py

@@ -9,6 +9,7 @@
 class OpenSenseMap:
     def __init__(self, base_url):
         self.base_url = base_url
+        self.fail_count = 0
 
     def get_avg_temperature(self, sense_boxes=None):
         temperature_info = []
@@ -21,14 +22,15 @@ def get_avg_temperature(self, sense_boxes=None):
                 return (
                     ({"avg_temp": 0, "status": "Internal Error"}),
                     HTTPStatus.INTERNAL_SERVER_ERROR,
+                    self.fail_count,
                 )
 
             if response.status_code == HTTPStatus.OK:
                 temperature_info.append(
                     self._process_temperature_data(data=response.json())
                 )
             else:
-                pass  # check stage increment a failure counter
+                self.fail_count += 1
 
         if temperature_info:
             avg_temp = sum(temperature_info) / len(temperature_info)
@@ -42,11 +44,13 @@ def get_avg_temperature(self, sense_boxes=None):
             return (
                 ({"avg_temp": round(number=avg_temp, ndigits=2), "status": status}),
                 HTTPStatus.OK,
+                self.fail_count,
             )
 
         return (
             ({"avg_temp": 0, "status": "Internal Error"}),
             HTTPStatus.INTERNAL_SERVER_ERROR,
+            self.fail_count,
         )
 
     def _process_temperature_data(self, data):
@@ -79,4 +83,4 @@ def _process_temperature_data(self, data):
                     if date_diff_in_hours < 24 and temperature_value != "":
                         return float(temperature_value)
 
-        return None  # handle none
+        return None