Guzzle

vs

Postman

With RestCase you can supercharges the API development process resulting in improved team collaboration, reduced development time, better testing and increased overall productivity. The cloud-based platform allows teams to collaboratively create REST and ASYNC APIs using an intuitive browser-based visual designer, automatically generate documentation, tests and mocks. The platform further enables rapid iteration and testing by creating a mock of the API that any team member can make calls against immediately without waiting for the actual development and deployment of the API, eliminating impediments from various development teams.

With Insomnia you can design, debug and deploy APIs. Insomnia is free API design platform and REST Client developed for macOS, Linux and Window. The application makes it easy to create and group requests, specify environment variables, authentication and generate code snippets. You can also get all the details on responses. View the whole request timeline, status codes, body, headers, cookies and much more. The software also makes it easy to orginize your projects with workspaces, folders, environments, drag-and-drop requests, and easily import and export your data. Insomnia integrates with API gateways such as the Kong API Gateway, and Kong for Kubernetes. While Insomnia comes with a free-forever license, the software provides premium monthly subscriptions for E2EE data sync and advanced collaboration features.

Developed by SmartBear Software, Swagger Inspector is an API testing tool that helps you design, develop and test web services. Whether its a REST, SOAP, or GraphQL, Swagger Inspector simplifies testing across your APIs. Inspector puts no limits to how you test, explore or generate your definitions from any form or type of API. The web-based software is released as a part of the Swagger eco-system which allow people to build self-documenting and well maintained APIs and web services.

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