Back to Repositories

Testing Kubernetes LimitRange Configuration in Apache Airflow

This test suite validates the implementation of Kubernetes LimitRange configurations in Apache Airflow’s Helm charts. It ensures proper resource constraints management and validates the correct rendering of limit range templates.

Test Coverage Overview

The test suite provides comprehensive coverage of Kubernetes LimitRange functionality in Airflow’s Helm charts.

Key areas tested include:

LimitRange template rendering with specified CPU constraints
Default behavior verification when no limits are specified
Resource limit validation for container configurations

Implementation Analysis

The testing approach utilizes Helm template rendering and JMESPath queries to validate LimitRange configurations. The implementation follows a declarative pattern, using render_chart utility to generate and verify Kubernetes manifest outputs.

The tests leverage JMESPath for precise JSON path extraction and validation of rendered templates.

Technical Details

Testing tools and components:

Helm template generator for chart rendering
JMESPath for JSON/YAML parsing and validation
Python unit test framework
Custom render_chart utility for template generation

Best Practices Demonstrated

The test suite exemplifies several testing best practices in Helm chart validation.

Notable practices include:

Isolated template rendering for focused testing
Explicit validation of both positive and negative cases
Clear separation of test scenarios
Efficient use of template rendering utilities

apache/airflow

helm_tests/other/test_limit_ranges.py

            
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
from __future__ import annotations

import jmespath

from tests.charts.helm_template_generator import render_chart


class TestLimitRanges:
    """Tests limit ranges."""

    def test_limit_ranges_template(self):
        docs = render_chart(
            values={"limits": [{"max": {"cpu": "500m"}, "min": {"min": "200m"}, "type": "Container"}]},
            show_only=["templates/limitrange.yaml"],
        )
        assert jmespath.search("kind", docs[0]) == "LimitRange"
        assert jmespath.search("spec.limits[0].max.cpu", docs[0]) == "500m"

    def test_limit_ranges_are_not_added_by_default(self):
        docs = render_chart(show_only=["templates/limitrange.yaml"])
        assert docs == []