From 6382643c26fb33fb1c2975445874e9ba6280d6a9 Mon Sep 17 00:00:00 2001
From: Alex Whitehead-Smith <alex.me.smith@gmail.com>
Date: Mon, 25 Nov 2024 20:29:37 +0000
Subject: [PATCH] Add a handler to delete a recipe

We'll pass the recipe ID through as a path parameter - similar to
getting a single recipe
---
 backend/handlers/recipes/delete.py            | 19 +++++++++++
 backend/models/recipe.py                      |  6 ++++
 backend/services/dynamodb.py                  |  3 ++
 backend/tests/handlers/recipes/test_delete.py | 33 +++++++++++++++++++
 backend/tests/models/test_recipe.py           |  8 +++++
 backend/tests/services/test_dynamodb.py       | 10 ++++++
 6 files changed, 79 insertions(+)
 create mode 100644 backend/handlers/recipes/delete.py
 create mode 100644 backend/tests/handlers/recipes/test_delete.py

diff --git a/backend/handlers/recipes/delete.py b/backend/handlers/recipes/delete.py
new file mode 100644
index 0000000..f7e6717
--- /dev/null
+++ b/backend/handlers/recipes/delete.py
@@ -0,0 +1,19 @@
+from aws_lambda_powertools.utilities.data_classes import APIGatewayProxyEventV2
+from aws_lambda_powertools.utilities.typing import LambdaContext
+
+
+from backend.models.recipe import Recipe
+from backend.services.logger import get_logger
+from backend.models.response import APIGatewayResponse
+
+logger = get_logger("recipes-delete")
+
+
+@logger.inject_lambda_context
+def handler(
+    event: APIGatewayProxyEventV2, context: LambdaContext
+) -> APIGatewayResponse:
+    id = event["pathParameters"]["id"]
+    recipe = Recipe.find_one(id=id)
+    recipe.delete()
+    return APIGatewayResponse.build(body={})
diff --git a/backend/models/recipe.py b/backend/models/recipe.py
index d72273e..9af749e 100644
--- a/backend/models/recipe.py
+++ b/backend/models/recipe.py
@@ -130,3 +130,9 @@ def save(self) -> None:
             self.client = Recipe._init_client()
 
         self.client.put_item("recipe", self.to_dict())
+
+    def delete(self) -> None:
+        if self.client is None:
+            self.client = Recipe._init_client()
+
+        self.client.delete_item("recipe", self.id)
diff --git a/backend/services/dynamodb.py b/backend/services/dynamodb.py
index d75854b..5dbee1f 100644
--- a/backend/services/dynamodb.py
+++ b/backend/services/dynamodb.py
@@ -44,3 +44,6 @@ def get_item(self, partition_key: str, sort_key: str) -> Optional[dict[str, Any]
             return result["Item"]
         else:
             return None
+
+    def delete_item(self, partition_key: str, sort_key: str) -> None:
+        self.table.delete_item(Key={"item_type": partition_key, "id": sort_key})
diff --git a/backend/tests/handlers/recipes/test_delete.py b/backend/tests/handlers/recipes/test_delete.py
new file mode 100644
index 0000000..787f3f6
--- /dev/null
+++ b/backend/tests/handlers/recipes/test_delete.py
@@ -0,0 +1,33 @@
+from sys import path
+import json
+from unittest.mock import patch, MagicMock
+from aws_lambda_powertools.utilities.data_classes import APIGatewayProxyEventV2
+from backend.tests.fixtures import LAMBDA_CONTEXT
+from backend.handlers.recipes.delete import handler
+
+API_GATEWAY_EVENT_WITH_RECIPE_ID = APIGatewayProxyEventV2(
+    {"body": "", "pathParameters": {"id": "recipe_id"}}
+)
+
+
+class TestRecipesDeleteHandler:
+
+    @patch("backend.handlers.recipes.delete.Recipe")
+    def test_handler_returns_a_dict_with_correct_fields(self, recipe_mock: MagicMock):
+        response = handler(API_GATEWAY_EVENT_WITH_RECIPE_ID, LAMBDA_CONTEXT)
+        for response_key in [
+            "body",
+            "statusCode",
+            "cookies",
+            "headers",
+            "isBase64Encoded",
+        ]:
+            assert response_key in response.keys()
+
+    @patch("backend.handlers.recipes.delete.Recipe")
+    def test_handler_calls_delete_on_the_recipe(self, recipe_mock: MagicMock):
+        found_recipe_mock = MagicMock()
+        recipe_mock.find_one.return_value = found_recipe_mock
+        handler(API_GATEWAY_EVENT_WITH_RECIPE_ID, LAMBDA_CONTEXT)
+
+        found_recipe_mock.delete.assert_called_once
diff --git a/backend/tests/models/test_recipe.py b/backend/tests/models/test_recipe.py
index 0dfe019..4373569 100644
--- a/backend/tests/models/test_recipe.py
+++ b/backend/tests/models/test_recipe.py
@@ -171,3 +171,11 @@ def test_find_one_returns_none_if_no_match(self, dynamodb_mock: MagicMock):
         recipe = Recipe.find_one("test")
 
         assert recipe is None
+
+    @patch("backend.models.recipe.DynamoDBClient")
+    def test_delete_calls_dynamo_client_with_id(self, dynamodb_mock: MagicMock):
+        recipe = Recipe.from_dict(RECIPE_DICT)
+        recipe.delete()
+        dynamodb_mock.return_value.delete_item.assert_called_once_with(
+            "recipe", recipe.id
+        )
diff --git a/backend/tests/services/test_dynamodb.py b/backend/tests/services/test_dynamodb.py
index 6215c8f..03c348e 100644
--- a/backend/tests/services/test_dynamodb.py
+++ b/backend/tests/services/test_dynamodb.py
@@ -74,3 +74,13 @@ def test_get_item_returns_one_item(self):
         assert item == mock_item
 
         del environ["DYNAMODB_TABLE_NAME"]
+
+    def test_delete_item_passes_through_the_id(self):
+        environ["DYNAMODB_TABLE_NAME"] = "TEST"
+        table_mock = Mock()
+        client = DynamoDBClient(table=table_mock)
+        client.delete_item("test_type", "test_id")
+
+        table_mock.delete_item.assert_called_once_with(
+            Key={"item_type": "test_type", "id": "test_id"}
+        )