OpenAPI Generator vs PostGraphile

OpenAPI Generator produces API clients, server stubs, and documentation from OpenAPI 2.0 and 3.x documents. It offers more than 50 client generators and server stub generation for over 40 languages and technologies, including Java, Kotlin, Go, and PHP. Other outputs include Apache2 configuration, MySQL, GraphQL schemas, and formats such as HTML and Cwiki. It can also convert OpenAPI 2.0 documents into OpenAPI 3.x JSON or YAML. Generated output can be adapted with Mustache templates, configuration-provided files and extensions, or custom generators. Installation choices include npm, Homebrew, Scoop, PyPI, Docker, JAR, JBang, and a Bash launcher. The project documents Gradle, Maven, sbt, Bazel, GitHub, and CI/CD integrations. Supported operating systems include Linux, macOS, and Windows, though installer availability varies by system. The JAR option requires Java 11 or later. The project is free and describes a Slack community for questions and guidance.

PostGraphile creates GraphQL APIs backed primarily by PostgreSQL, for applications such as SaaS backends and internal business tools. Its core features include GraphQL queries and mutations, automatic CRUD mutations, filtering, ordering, plugins, and authentication using JWT or custom pgSettings. It also supports row-level security and role-based access control. PostGraphile V4 Core and Version 5 are open source under the MIT license. Version 5 is built on Grafast, a planning and execution engine intended to improve performance and maintainability. The project can be self-hosted, and its homepage offers an `npx pgl` command to start with a PostgreSQL connection string. PostGraphile Pro adds query-cost, pagination, and query-depth limits, as well as a facility for scaling through database read replicas. The Pro plugin is for V4 Core; Version 5 remains open source and under development. V4 Core costs nothing. Pro License Only costs $25 a month, with up to four production instances and 100 development instances; larger clusters require custom licensing.