Merge pull request #57 from ajschofield/test-extract-v2

pr: update extract_lambda tests

1 files changed, 125 insertions, 30 deletions

diff --git a/tests/test_extract_lambda.py b/tests/test_extract_lambda.py
index e94a8a4..67cb6d3 100644
--- a/tests/test_extract_lambda.py
+++ b/tests/test_extract_lambda.py
@@ -3,11 +3,19 @@ import boto3
 from moto import mock_aws
 from unittest.mock import patch, MagicMock
 from unittest import TestCase
-from src.extract_lambda import list_existing_s3_files, connect_to_database, DBConnectionException, process_and_upload_tables
-import os 
+from src.extract_lambda import (
+    list_existing_s3_files,
+    connect_to_database,
+    DBConnectionException,
+    lambda_handler,
+    process_and_upload_tables,
+)
+import os
 import logging
+import json
 
-@pytest.fixture(scope='class')
+
+@pytest.fixture(scope="class")
 def mock_config():
     env_vars = {
         "host": "abc",
@@ -20,54 +28,139 @@ def mock_config():
         yield mock_config
 
 
-@pytest.fixture(scope='class')
+@pytest.fixture(scope="class")
 def aws_credentials():
-    os.environ["AWS_ACCESS_KEY_ID"] = 'testing'
-    os.environ["AWS_SECRET_ACCESS_KEY"] = 'testing'
-    os.environ["AWS_SECURIT_TOKEN"] = 'testing'
-    os.environ["AWS_SESSION_TOKEN"] = 'testing'
-    os.environ["AWS_DEFAULT_REGION"]= 'eu-west-2'
+    os.environ["AWS_ACCESS_KEY_ID"] = "testing"
+    os.environ["AWS_SECRET_ACCESS_KEY"] = "testing"
+    os.environ["AWS_SECURIT_TOKEN"] = "testing"
+    os.environ["AWS_SESSION_TOKEN"] = "testing"
+    os.environ["AWS_DEFAULT_REGION"] = "eu-west-2"
+
 
-@pytest.fixture(scope='class')
+@pytest.fixture(scope="class")
 def s3_client(aws_credentials):
     with mock_aws():
-        yield boto3.client('s3')
+        yield boto3.client("s3")
+
+
+class TestLambdaHandler:
+    def test_lambda_handler_files_processed_and_uploaded_successfully(self, mocker):
+        mock_db = MagicMock()
+        mock_db.run.side_effect = [
+            [["Fruits"]],
+            [["Vegetable", "Sour", "Green"], ["Berry", "Sweet", "Red"]],
+            [["Food_type"], ["Flavour"], ["Colour"]],
+        ]
+        mock_db.columns.return_value = [
+            {"name": "Food_type"},
+            {"name": "Flavour"},
+            {"name": "Colour"},
+        ]
+        with patch("src.extract_lambda.connect_to_database", return_value=mock_db):
+            mock_process_and_upload_tables = mocker.patch(
+                "src.extract_lambda.process_and_upload_tables", return_value=mock_db
+            )
+            mock_list_existing_s3_files = mocker.patch(
+                "src.extract_lambda.list_existing_s3_files", return_value={}
+            )
+            event = {}
+            context = {}
+            response = lambda_handler(event, context)
+            assert response["statusCode"] == 200
+            assert (
+                json.loads(response["body"])
+                == "CSV files processed and uploaded successfully."
+            )
+            mock_list_existing_s3_files.assert_called_once()
+            mock_process_and_upload_tables.assert_called_once_with(mock_db, {})
+            mock_db.close.assert_called_once()
+
+    def test_lambda_handler_no_changes_detected_no_files_uploaded(self, mocker):
+        mock_db = MagicMock()
+        mock_db.run.side_effect = [
+            [["Fruits"]],
+            [["Vegetable", "Sour", "Green"], ["Berry", "Sweet", "Red"]],
+            [["Food_type"], ["Flavour"], ["Colour"]],
+        ]
+        mock_db.columns.return_value = [
+            {"name": "Food_type"},
+            {"name": "Flavour"},
+            {"name": "Colour"},
+        ]
+
+        with patch("src.extract_lambda.connect_to_database", return_value=mock_db):
+            mock_process_and_upload_tables = mocker.patch(
+                "src.extract_lambda.process_and_upload_tables", return_value=False
+            )
+            mock_list_existing_s3_files = mocker.patch(
+                "src.extract_lambda.list_existing_s3_files", return_value={}
+            )
+            event = {}
+            context = {}
+            response = lambda_handler(event, context)
+            assert response["statusCode"] == 200
+            assert (
+                json.loads(response["body"])
+                == "No changes detected, no CSV files were uploaded."
+            )
+            mock_list_existing_s3_files.assert_called_once()
+            mock_process_and_upload_tables.assert_called_once_with(mock_db, {})
+            mock_db.close.assert_called_once()
+
+    def test_lambda_handler_exception_error(self, mocker):
+        with patch(
+            "src.extract_lambda.connect_to_database",
+            side_effect=Exception("Database connection error"),
+        ):
+            mock_process_and_upload_tables = mocker.patch(
+                "src.extract_lambda.process_and_upload_tables"
+            )
+            mock_list_existing_s3_files = mocker.patch(
+                "src.extract_lambda.list_existing_s3_files"
+            )
+            event = {}
+            context = {}
+            response = lambda_handler(event, context)
+            assert response["statusCode"] == 500
+            assert json.loads(response["body"]) == "Internal server error."
+            mock_list_existing_s3_files.assert_not_called()
+            mock_process_and_upload_tables.assert_not_called()
+
 
 class TestListExistingS3Files:
     def test_error_if_no_bucket(self, s3_client, caplog):
-
         logger = logging.getLogger()
-        logger.info('Testing now.')
+        logger.info("Testing now.")
         caplog.set_level(logging.ERROR)
         list_existing_s3_files(client=s3_client)
-        assert 'Error listing S3 objects' in caplog.text
+        assert "Error listing S3 objects" in caplog.text
 
     def test_error_if_bucket_is_empty(self, s3_client, caplog):
-
-        s3_client.create_bucket(Bucket='extract_bucket', 
-                                CreateBucketConfiguration={
-                                    'LocationConstraint': 'eu-west-2'
-                                })
+        s3_client.create_bucket(
+            Bucket="extract_bucket",
+            CreateBucketConfiguration={"LocationConstraint": "eu-west-2"},
+        )
         list_existing_s3_files(client=s3_client)
-        assert 'The bucket is empty' in caplog.text 
+        assert "The bucket is empty" in caplog.text
 
     def test_error_retrieving_object(self, s3_client, caplog):
-        s3_client.upload_file('tests/dummy.txt', 'extract_bucket', 'dummy.txt')
-        list_existing_s3_files(bucket_name='test_bucket', client=s3_client)
+        s3_client.upload_file("tests/dummy.txt", "extract_bucket", "dummy.txt")
+        list_existing_s3_files(bucket_name="test_bucket", client=s3_client)
 
-        assert 'Error retrieving S3 object ' in caplog.text
+        assert "Error retrieving S3 object " in caplog.text
 
     def test_retrieves_file_content(self, s3_client, caplog):
         result = list_existing_s3_files(client=s3_client)
 
-        assert list(result.values()) == ['This is a test file.'] 
+        assert list(result.values()) == ["This is a test file."]
+
 
 class TestConnectToDatabase:
     def test_connect_to_database(mock_conn, mock_config):
-        with patch("src.extract_lambda.Connection", autospec=True) as mock_conn:  
+        with patch("src.extract_lambda.Connection", autospec=True) as mock_conn:
             connect_to_database()
             mock_conn.assert_called_with(
-            host="abc", user="def", port="5432", password="password", database="db"
+                host="abc", user="def", port="5432", password="password", database="db"
             )
 
     def test_database_error(self, mock_config):
@@ -76,12 +169,14 @@ class TestConnectToDatabase:
 
     def test_logs_interface_error(self, caplog):
         logger = logging.getLogger()
-        logger.info('Testing now.')
+        logger.info("Testing now.")
         caplog.set_level(logging.ERROR)
         with pytest.raises(DBConnectionException):
             connect_to_database()
-        assert 'Interface error' in caplog.text
-'''
+        assert "Interface error" in caplog.text
+
+
+"""
 class TestProcessAndUploadTables:
     def test_error_process_and_upload_tables(mock_conn, mock_config, s3_client, caplog):
         logger = logging.getLogger()
@@ -106,4 +201,4 @@ class TestProcessAndUploadTables:
             s3_client.upload_file('tests/dummy_identical.csv', 'extract_bucket', s3_key)
             process_and_upload_tables(mock_db(), existing_files, client=s3_client)
             assert 'No new data.' in caplog.text
-'''
\ No newline at end of file
+"""