skips airflow tests if not installed

Makefile

@@ -82,7 +82,7 @@ lint-security:
 	poetry run bandit -r dlt/ -n 3 -l
 
 test:
-	(set -a && . tests/.env && poetry run pytest tests)
+	poetry run pytest tests
 
 test-load-local:
 	DESTINATION__POSTGRES__CREDENTIALS=postgresql://loader:loader@localhost:5432/dlt_data DESTINATION__DUCKDB__CREDENTIALS=duckdb:///_storage/test_quack.duckdb  poetry run pytest tests -k '(postgres or duckdb)'

tests/helpers/airflow_tests/test_airflow_provider.py

@@ -1,3 +1,7 @@
+import pytest
+
+pytest.importorskip("apache-airflow")
+
 from airflow import DAG
 from airflow.decorators import task, dag
 from airflow.operators.python import PythonOperator

tests/helpers/airflow_tests/test_airflow_wrapper.py

@@ -2,6 +2,8 @@
 import pytest
 from unittest import mock
 from typing import Iterator, List
+
+pytest.importorskip("apache-airflow")
 from airflow import DAG
 from airflow.decorators import dag
 from airflow.operators.python import PythonOperator, get_current_context

tests/helpers/airflow_tests/test_join_airflow_scheduler.py

@@ -1,5 +1,8 @@
+import pytest
 import datetime
 from pendulum.tz import UTC
+
+pytest.importorskip("apache-airflow")
 from airflow import DAG
 from airflow.decorators import dag, task
 from airflow.models import DagRun

tests/helpers/airflow_tests/utils.py

@@ -2,9 +2,6 @@
 import os
 import argparse
 import pytest
-from airflow.cli.commands.db_command import resetdb
-from airflow.configuration import conf
-from airflow.models.variable import Variable
 
 from dlt.common.configuration.container import Container
 from dlt.common.configuration.specs import PluggableRunContext
@@ -19,6 +16,8 @@
 
 @pytest.fixture(scope="function", autouse=True)
 def initialize_airflow_db():
+    from airflow.models.variable import Variable
+
     setup_airflow()
     # backup context providers
     providers = Container()[PluggableRunContext].providers
@@ -35,6 +34,9 @@ def initialize_airflow_db():
 
 
 def setup_airflow() -> None:
+    from airflow.cli.commands.db_command import resetdb
+    from airflow.configuration import conf
+
     # Disable loading examples
     try:
         conf.add_section("core")