2 files changed, 113 insertions, 0 deletions
diff --git a/tests/dummy.txt b/tests/dummy.txt
new file mode 100644
index 0000000..af27ff4
--- /dev/null
+++ b/tests/dummy.txt
@@ -0,0 +1 @@
+This is a test file.
+\ No newline at end of file
diff --git a/tests/test_extract_lambda.py b/tests/test_extract_lambda.py
new file mode 100644
index 0000000..74d7e2c
--- /dev/null
+++ b/tests/test_extract_lambda.py
@@ -0,0 +1,112 @@
+import pytest
+import boto3
+from moto import mock_aws
+from unittest.mock import patch
+from unittest import TestCase
+from src.extract_lambda import list_existing_s3_files, connect_to_database, DBConnectionException, process_and_upload_tables
+import os 
+import logging
+
+@pytest.fixture(scope='class')
+def mock_config():
+    env_vars = {
+        "host": "abc",
+        "port": "5432",
+        "user": "def",
+        "password": "password",
+        "database": "db",
+    }
+    with patch("src.extract_lambda.get_config", return_value=env_vars) as mock_config:
+        yield mock_config
+
+
+@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'
+
+@pytest.fixture(scope='class')
+def s3_client(aws_credentials):
+    with mock_aws():
+        yield boto3.client('s3')
+
+class TestListExistingS3Files:
+    def test_error_if_no_bucket(self, s3_client, caplog):
+
+        logger = logging.getLogger()
+        logger.info('Testing now.')
+        caplog.set_level(logging.ERROR)
+        list_existing_s3_files(client=s3_client)
+        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'
+                                })
+        list_existing_s3_files(client=s3_client)
+        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)
+
+        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.'] 
+
+class TestConnectToDatabase:
+    def test_connect_to_database(mock_conn, mock_config):
+        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"
+            )
+
+    def test_database_error(self, mock_config):
+        with pytest.raises(DBConnectionException):
+            connect_to_database()
+
+    def test_logs_interface_error(self, caplog):
+        logger = logging.getLogger()
+        logger.info('Testing now.')
+        caplog.set_level(logging.ERROR)
+        with pytest.raises(DBConnectionException):
+            connect_to_database()
+        assert 'Interface error' in caplog.text
+
+class TestProcessAndUploadTables:
+    def test_error_process_and_upload_tables(mock_conn, mock_config, s3_client, caplog, mocker):
+        logger = logging.getLogger()
+        logger.info('Testing now.')
+        caplog.set_level(logging.ERROR)
+
+        with patch("src.extract_lambda.Connection", autospec=True) as mock_conn:
+            mock_db = connect_to_database()
+            # need to add a table 
+            s3_key = 'dummy/2024/8/14/dummy_16:46:30.txt'
+            mock_existing_files = mocker.Mock(return_value={s3_key: 'This is a test file.' })
+            s3_client.create_bucket(Bucket='extract_bucket', 
+                        CreateBucketConfiguration={
+                            'LocationConstraint': 'eu-west-2'
+                        })
+            s3_client.upload_file('tests/dummy.txt', 'extract_bucket', s3_key)
+            process_and_upload_tables(mock_db, mock_existing_files, client=s3_client)
+
+            assert 'Error uploading to S3' in caplog.text
+
+#@pytest.mark.describe("Helpers")
+# @pytest.mark.it("Query processor returns correctly formatted dict")
+# def test_process_query():
+#     with patch("src.api.helpers.get_db_connection") as mock_conn:
+#         mock_conn().run.side_effect = db_data
+#         mock_conn().columns = sample_headers
+#         result = process_query("test query")
+#         assert result == sample_result
+\ No newline at end of file