Add lambda handler

canary.py

@@ -0,0 +1,38 @@
+import os
+from datetime import datetime
+from urllib.request import Request, urlopen
+
+SITE = os.environ['site']  # URL of the site to check, stored in the site environment variable
+EXPECTED = os.environ['expected']  # String expected to be on the page, stored in the expected environment variable
+
+
+def validate(res):
+    """
+    Return False to trigger the canary
+
+    Currently this simply checks whether the EXPECTED string is present.
+    However, you could modify this to perform any number of arbitrary
+    checks on the contents of SITE.
+    """
+
+    return EXPECTED in res
+
+
+def lambda_handler(event, context):
+    print(f"Checking {SITE} at {event['time']}...")
+
+    try:
+        req = Request(SITE, headers={'User-Agent': 'AWS Lambda'})
+        if not validate(str(urlopen(req).read())):
+            raise Exception('Validation failed')
+
+    except Exception:
+        print('Check failed!')
+        raise
+
+    else:
+        print('Check passed!')
+        return event['time']
+
+    finally:
+        print(f"Checking complete at {str(datetime.now())}")

main.py

@@ -1,16 +0,0 @@
-# This is a sample Python script.
-
-# Press Shift+F10 to execute it or replace it with your code.
-# Press Double Shift to search everywhere for classes, files, tool windows, actions, and settings.
-
-
-def print_hi(name):
-    # Use a breakpoint in the code line below to debug your script.
-    print(f'Hi, {name}')  # Press Ctrl+F8 to toggle the breakpoint.
-
-
-# Press the green button in the gutter to run the script.
-if __name__ == '__main__':
-    print_hi('PyCharm')
-
-# See PyCharm help at https://www.jetbrains.com/help/pycharm/