Events - send events to (subset of) targets

docs/docs/services/events.rst

@@ -12,6 +12,8 @@
 events
 ======
 
+.. autoclass:: moto.events.models.EventsBackend
+
 |start-h3| Example usage |end-h3|
 
 .. sourcecode:: python

moto/events/models.py

@@ -824,6 +824,9 @@ def __init__(self, raw_pattern, pattern):
         self._raw_pattern = raw_pattern
         self._pattern = pattern
 
+    def get_pattern(self):
+        return self._pattern
+
     def matches_event(self, event):
         if not self._pattern:
             return True
@@ -921,6 +924,14 @@ def parse(self):
 
 
 class EventsBackend(BaseBackend):
+    """
+    When a event occurs, the appropriate targets are triggered for a subset of usecases.
+
+    Supported events: S3:CreateBucket
+
+    Supported targets: AWSLambda functions
+    """
+
     ACCOUNT_ID = re.compile(r"^(\d{1,12}|\*)$")
     STATEMENT_ID = re.compile(r"^[a-zA-Z0-9-_]{1,64}$")
     _CRON_REGEX = re.compile(r"^cron\(.*\)")

moto/events/notifications.py

@@ -0,0 +1,65 @@
+import json
+
+
+_EVENT_S3_OBJECT_CREATED = {
+    "version": "0",
+    "id": "17793124-05d4-b198-2fde-7ededc63b103",
+    "detail-type": "Object Created",
+    "source": "aws.s3",
+    "account": "123456789012",
+    "time": "2021-11-12T00:00:00Z",
+    "region": None,
+    "resources": [],
+    "detail": None,
+}
+
+
+def send_notification(source, event_name, region, resources, detail):
+    try:
+        _send_safe_notification(source, event_name, region, resources, detail)
+    except:  # noqa
+        # If anything goes wrong, we should never fail
+        pass
+
+
+def _send_safe_notification(source, event_name, region, resources, detail):
+    from .models import events_backends
+
+    event = None
+    if source == "aws.s3" and event_name == "CreateBucket":
+        event = _EVENT_S3_OBJECT_CREATED.copy()
+        event["region"] = region
+        event["resources"] = resources
+        event["detail"] = detail
+
+    if event is None:
+        return
+
+    for backend in events_backends.values():
+        applicable_targets = []
+        for rule in backend.rules.values():
+            if rule.state != "ENABLED":
+                continue
+            pattern = rule.event_pattern.get_pattern()
+            if source in pattern.get("source", []):
+                if event_name in pattern.get("detail", {}).get("eventName", []):
+                    applicable_targets.extend(rule.targets)
+
+        for target in applicable_targets:
+            if target.get("Arn", "").startswith("arn:aws:lambda"):
+                _invoke_lambda(target.get("Arn"), event=event)
+
+
+def _invoke_lambda(fn_arn, event):
+    from moto.awslambda import lambda_backends
+
+    lmbda_region = fn_arn.split(":")[3]
+
+    body = json.dumps(event)
+    lambda_backends[lmbda_region].invoke(
+        function_name=fn_arn,
+        qualifier=None,
+        body=body,
+        headers=dict(),
+        response_headers=dict(),
+    )

moto/s3/models.py

@@ -58,6 +58,7 @@
 from .cloud_formation import cfn_to_api_encryption, is_replacement_update
 from . import notifications
 from .utils import clean_key_name, _VersionedKeyStore, undo_clean_key_name
+from ..events.notifications import send_notification as events_send_notification
 from ..settings import get_s3_default_key_buffer_size, S3_UPLOAD_PART_MIN_SIZE
 
 MAX_BUCKET_NAME_LENGTH = 63
@@ -1463,6 +1464,23 @@ def create_bucket(self, bucket_name, region_name):
         new_bucket = FakeBucket(name=bucket_name, region_name=region_name)
 
         self.buckets[bucket_name] = new_bucket
+
+        notification_detail = {
+            "version": "0",
+            "bucket": {"name": bucket_name},
+            "request-id": "N4N7GDK58NMKJ12R",
+            "requester": get_account_id(),
+            "source-ip-address": "1.2.3.4",
+            "reason": "PutObject",
+        }
+        events_send_notification(
+            source="aws.s3",
+            event_name="CreateBucket",
+            region=region_name,
+            resources=[f"arn:aws:s3:::{bucket_name}"],
+            detail=notification_detail,
+        )
+
         return new_bucket
 
     def list_buckets(self):