feat: Add alb lambda event support to Parser utility #228

Author: Ran Isenberg

aws_lambda_powertools/utilities/parser/models/__init__.py

@@ -1,10 +1,14 @@
+from .alb import AlbModel, AlbRequestContext, AlbRequestContextData
 from .dynamodb import DynamoDBStreamChangedRecordModel, DynamoDBStreamModel, DynamoDBStreamRecordModel
 from .event_bridge import EventBridgeModel
 from .ses import SesModel, SesRecordModel
 from .sns import SnsModel, SnsNotificationModel, SnsRecordModel
 from .sqs import SqsModel, SqsRecordModel
 
 __all__ = [
+    "AlbModel",
+    "AlbRequestContext",
+    "AlbRequestContextData",
     "DynamoDBStreamModel",
     "EventBridgeModel",
     "DynamoDBStreamChangedRecordModel",

aws_lambda_powertools/utilities/parser/models/alb.py

@@ -0,0 +1,21 @@
+from typing import Dict
+
+from pydantic import BaseModel
+
+
+class AlbRequestContextData(BaseModel):
+    targetGroupArn: str
+
+
+class AlbRequestContext(BaseModel):
+    elb: AlbRequestContextData
+
+
+class AlbModel(BaseModel):
+    httpMethod: str
+    path: str
+    body: str
+    isBase64Encoded: bool
+    headers: Dict[str, str]
+    queryStringParameters: Dict[str, str]
+    requestContext: AlbRequestContext

tests/functional/parser/test_alb.py

@@ -0,0 +1,44 @@
+import pytest
+
+from aws_lambda_powertools.utilities.parser import ValidationError, event_parser
+from aws_lambda_powertools.utilities.parser.models import AlbModel
+from aws_lambda_powertools.utilities.typing import LambdaContext
+from tests.functional.parser.utils import load_event
+
+
+@event_parser(model=AlbModel)
+def handle_alb(event: AlbModel, _: LambdaContext):
+    assert (
+        event.requestContext.elb.targetGroupArn
+        == "arn:aws:elasticloadbalancing:us-east-2:123456789012:targetgroup/lambda-279XGJDqGZ5rsrHC2Fjr/49e9d65c45c6791a"  # noqa E501
+    )
+    assert event.httpMethod == "GET"
+    assert event.path == "/lambda"
+    assert event.queryStringParameters == {"query": "1234ABCD"}
+    assert event.headers == {
+        "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8",
+        "accept-encoding": "gzip",
+        "accept-language": "en-US,en;q=0.9",
+        "connection": "keep-alive",
+        "host": "lambda-alb-123578498.us-east-2.elb.amazonaws.com",
+        "upgrade-insecure-requests": "1",
+        "user-agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36",  # noqa E501
+        "x-amzn-trace-id": "Root=1-5c536348-3d683b8b04734faae651f476",
+        "x-forwarded-for": "72.12.164.125",
+        "x-forwarded-port": "80",
+        "x-forwarded-proto": "http",
+        "x-imforwards": "20",
+    }
+    assert event.body == "Test"
+    assert not event.isBase64Encoded
+
+
+def test_alb_trigger_event():
+    event_dict = load_event("albEvent.json")
+    handle_alb(event_dict, LambdaContext())
+
+
+def test_validate_event_does_not_conform_with_model():
+    event = {"invalid": "event"}
+    with pytest.raises(ValidationError):
+        handle_alb(event, LambdaContext())