joist-graphql-codegen

This is an optional extension to Joist's codegen logic to generate additional GraphQL-specific output.

The core joist-orm/etc. is GraphQL/REST/etc. agnostic, but pragmatically much of Joist's development is driven by implementing a TypeScript/Apollo GraphQL service, so this module helps with some of the glue code.

Configuration

In your joist-codegen.json add an additional setting:

{
  "codegenPlugins": ["joist-graphql-codegen"]
}

Generated files

This will generate:

• schema/enums.graphql with a GraphQL version of each Joist/domain enum

  For entities, Joist takes an "arms-length" stance on GraphqL integration, i.e. a GraphQL entity type Book will probably match 80% of the Joist domain entity type Book, but the last 20% will be bespoke, and so the two need to float independently.

  This arms-length caution seems less necessary for enums, so enums.graphql will contain a one-to-one mapping of GraphQL enums that exactly the domain enums.

• src/resolvers/enumResolvers.ts includes resolvers for the "enum detail" pattern

  Given "turn this code into a name" if a frequent operation for frontends, our enum detail pattern allows wrapping each enum with an object type that exposes both the code (i.e. the enum value itself) as well as the name (as driven by the name column in the enum's database table).

• ./graphql-codegen-joist.js contains mappers and enumValues config values to require into your primary graphql-codegen.js file.

  mappers declares every entity as a mapped type to its strongly-typed id, i.e. Book: BookId (which becomes the root type of the entity's resolver).

  enumValues tells graphql-code-generator to use the existing/Joist-generated src/entities enum declarations instead of re-creating its own enums in graphql-types.ts.

Todo

• Remove the hard-coded file paths like @src/resolvers/etc.