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Nexus to Pothos codemod

npm version PRs Welcome

This is a codemod to migrate from Nexus to Pothos

This aims to transform all the nexus types, queries and mutations to Pothos equivalents. Please note that the codemod is by no means complete. You still need some manual adjustments. Below is a list of known missing features.

You can check out the __textfixtures__ folder to see full list of supported transformations.

Why should I migrate to use Pothos?

  • Pothos has superior type safety
  • Pothos does not require you to generate types which makes type feedback much much faster
  • Pothos is actively maintained

Install

$ yarn global add nexus-to-pothos-codemod

or

$ npm install -g nexus-to-pothos-codemod

Usage

$ nexus-to-pothos-codemod ./**/*.ts --ignore-pattern="**/node_modules/**" --parser=ts

The CLI is the same as in jscodeshift except you can omit the transform file.

Alternatively, you can run the codemod using jscodeshift as follows:

$ yarn global add jscodeshift
$ yarn add nexus-to-pothos-codemod
$ jscodeshift -t node_modules/nexus-to-pothos-codemod/transform.ts --ignore-pattern="**/node_modules/**" ./**/*.js  --parser=ts

Migrating the codebase

The codemod might not be 100% accurate. You will need to do some manual adjustments. Might be good to compare the generated GraphQL schema with the old one to see if there are any differences.

What is missing?

  • automatic import updates

  • it assumes some conventions such as async nodes((_, args, ctx) {} instead of nodes: async ((_, args, ctx) => {} which causes exceptions

  • does not understand computed fields such as:

    export const Object = objectType({
name: 'Object',
definition(t) {
  objectFields.forEach(objectField => t.string(objectField));
}
});

  • might fail on complex types

  • unionType not transformed

  • scalarType not transformed

  • lists not handled properly always, [] needs to be mostly added manually

  • args of connnectionField not transformed preoperly

  • authScope in connectionField and some nested fields not transformed properly

  • all caveats might not be discovered since the codemod is developed against single codebase with it's own conventions

Parts that causes exceptions can be commented out and fixed manually. Rest are fairly easy to compare to the old schema. Be extra careful with the authScope.

An example builder config:

import SchemaBuilder from '@pothos/core';
import RelayPlugin from '@pothos/plugin-relay';
import ScopeAuthPlugin from '@pothos/plugin-scope-auth';
import { GraphQLJSONObject } from 'graphql-type-json';

export const builder = new SchemaBuilder<{
  Context: {};
  DefaultEdgesNullability: false;
  DefaultNodeNullability: false;
  Scalars: {
    ID: {
      Output: number | string;
      Input: string;
    };
    JSONObject: {
      Output: object;
      Input: object;
    };
  };
}>({
  plugins: [ScopeAuthPlugin, RelayPlugin],
  authScopes: context => ({}),
  scopeAuthOptions: {
    unauthorizedError: () => new Error(`Not authorized`)
  },
  relayOptions: {
    clientMutationId: 'omit',
    cursorType: 'ID',
    edgesFieldOptions: {
      nullable: false
    },
    nodeFieldOptions: {
      nullable: false
    }
  }
});

builder.queryType();
builder.mutationType();
builder.addScalarType('JSONObject', GraphQLJSONObject, {});

Contributing

Contributions are more than welcome! Some useful tools for developing this are https://astexplorer.net/ and your editors builtin debugger.