ALPR Stats (#2)

* set up lambda to get total ALPR counts

* show total counts on map, updated hourly

serverless/alpr-counts/src/alpr_counts.py

@@ -0,0 +1,48 @@
+import json
+import requests
+import boto3
+
+def fetch_alpr_surveillance_nodes(usOnly=False):
+  overpass_url = "http://overpass-api.de/api/interpreter"
+  overpass_query = f"""
+  [out:json];
+  {'area["ISO3166-1"="US"]->.searchArea;' if usOnly else ''}
+  node["man_made"="surveillance"]["surveillance:type"="ALPR"]{f'(area.searchArea)' if usOnly else ''};
+  out count;
+  """
+
+  response = requests.get(overpass_url, params={'data': overpass_query})
+
+  if response.status_code == 200:
+    response_json = response.json()
+    try:
+      return response_json['elements'][0]['tags']['nodes']
+    except (IndexError, KeyError) as e:
+      return {"error": "Could not find 'elements[0].tags.nodes' in the response."}
+  else:
+    return {"error": f"Failed to fetch data from Overpass API. Status code: {response.status_code}"}
+
+def lambda_handler(event, context):
+  us_alprs = fetch_alpr_surveillance_nodes('(area["ISO3166-1"="US"])')
+  worldwide_alprs = fetch_alpr_surveillance_nodes()
+
+  all_alprs = {
+    'us': us_alprs,
+    'worldwide': worldwide_alprs
+  }
+
+  s3 = boto3.client('s3')
+  bucket = 'deflock-clusters'
+  key = 'alpr-counts.json'
+
+  s3.put_object(
+    Bucket=bucket,
+    Key=key,
+    Body=json.dumps(all_alprs),
+    ContentType='application/json'
+  )
+
+  return {
+    'statusCode': 200,
+    'body': 'Successfully fetched ALPR counts.',
+  }

serverless/alpr-counts/src/requirements.txt

@@ -0,0 +1,2 @@
+requests
+boto3