ts-graphql-plugin

TypeScript Language Service Plugin for GraphQL

Usage no npm install needed!

<script type="module">
  import tsGraphqlPlugin from 'https://cdn.skypack.dev/ts-graphql-plugin';
</script>

README

ts-graphql-plugin

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Provides functions to help TypeScript GraphQL client development including auto completion, query validation, type generation and so on.

capture

This plugin has the following features:

  • As TypeScript Language Service extension:
    • Completion suggestion
    • Get GraphQL diagnostics
    • Display GraphQL quick info within tooltip
  • As CLI
    • Generate ts type files from your GraphQL operations in your TypeScript sources
    • Extract or validate GraphQL operations in your TypeScript sources
  • As webpack plugin
    • Transform your queries to GraphQL AST object statically

ToC

Getting started

First, confirm that your project has typescript(v2.3.x or later) and graphql(v15.x.0 or later).

To install this plugin, execute the following:

npm install ts-graphql-plugin -D

And configure plugins section in your tsconfig.json, for example:

{
  "compilerOptions": {
    "module": "commonjs",
    "target": "es5",
    "plugins": [
      {
        "name": "ts-graphql-plugin",
        "schema": "path-or-url-to-your-schema.graphql",
        "tag": "gql"
      }
    ]
  }
}

It's ready to go. Launch your TypeScript IDE.

CLI Usage

$ npx ts-graphql-plugin <command> [options]

If you install this plugin, a short alias tsgql is also available instead of ts-graphql-plugin.

Available commands are typegen, extract, validate and report. If you want more detail, runts-graphql-plugin --helports-graphql-plugin <command> --help in your console.

typegen command

Generate TypeScript types from GraphQL operations or fragments in your .ts source files. Here is an output example.

extract command

Extracts GraphQL operations and fragments from ts files and writes them to manifest.json.

validate command

Validates your GraphQL operations and fragments in your ts files and report syntax or semantic errors.

report command

Extracts GraphQL operations and fragments from ts files and report them to a Markdown file. Here is an output example.

Plugin options

Pass plugin options to your tsconfig.json to configure this plugin.

/* tsconfig.json */
{
  "compilerOptions": {
    "plugins": [
      {
        "name": "ts-graphql-plugin",
        /* plugin options */
        "schema": "path-or-url-to-your-schema.graphql",
        "tag": "gql",
        ...
      }
    ]
  }
}

schema

It's a required parameter and should point your GraphQL schema SDL file such as :

type Author {
  id: ID!
  firstName: String
  lastName: String
  posts: [Post]
}
type Post {
  id: ID!
  title: String
  author: Author
  votes: Int
}
type Query {
  posts: [Post]
  author(id: ID!): Author
}

Also you can use GraphQL introspection query result data such as:

{
  "__schema": {
    "queryType": {
      "name": "Query"
    },
    "types": [
      {
        "kind": "OBJECT",
        "name": "Query",
        "description": null,
        "fields": [
          {
            "name": "viewer",
            :

You can pass URL and custom HTTP headers. It's useful to use an existing GraphQL server like GitHub v4 API. For example:

  "schema": {
    "http": {
      "url": "https://api.github.com/graphql",
      "headers": {
        "Authorization": "Bearer YOUR_GITHUB_API_TOKEN"
      }
    }
  },

If you need to use more complex logic like fetch bearer token using client secret then you can build your http schema configuration using javascript. First, you need to setup your plugin configuration like below:

  "schema": {
    "http": {
      "fromScript": "my-graphql-config.js"
    }
  },

Your script have to return valid RequestSetup or Promise<RequestSetup> object:

url: string;
method?: string; // default to 'POST'
headers?: { [key: string]: string };

Example how configuration script may look like:

// my-graphql-config.js
const fetch = require('node-fetch');

module.exports = projectRootPath =>
  new Promise(resolve => {
    fetch('http://localhost/identity-server/connect/token', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded',
      },
      body: `client_secret=${process.env.MY_CLIENT_SECRET}`,
    })
      .then(response => response.json())
      .then(response => {
        resolve({
          url: 'http://localhost/graphql',
          method: 'POST', // unnecessary, "POST" is default value
          headers: {
            Authorization: `Bearer ${response.access_token}`,
          },
        });
      });
  });

The schema option accepts the following type:

type SchemaConfig =
  | string
  | {
      file: {
        path: string;
      };
    }
  | {
      http: {
        url: string;
        method?: string;
        headers?: { [key: string]: string };
      };
    }
  | {
      http: {
        fromScript: string;
      };
    };

tag

It's optional. When it's set, this plugin works only if the target template string is tagged by a function whose name is equal to this parameter.

If not set, this plugin treats all template strings in your .ts as GraphQL query.

For example:

import gql from 'graphql-tag';

// when tag paramter is 'gql'
const str1 = gql`query { }`; // work
const str2 = `<div></div>`; // don't work
const str3 = otherTagFn`foooo`; // don't work

It's useful to write multiple kinds template strings(e.g. one is Angular Component template, another is Apollo GraphQL query).

localSchemaExtensions

It's optional. If you want to extend server-side schema, derived from schema option, you can set path of SDL file of your local extension.

For example:

# local-extension.graphql

directive @client on FIELD

type SomeClientOnlyType {
  name: String!
}

extend type Query {
  someLocalField: SomeClientOnlyType!
}
/* tsconfig.json */
{
  "compilerOptions": {
    "plugins": [
      {
        "name": "ts-graphql-plugin",
        "schema": "base-schema.graphql",
        "localSchemaExtensions": ["local-extension.graphql"]
      }
    ]
  }
}

The above example setting allows to write the following query:

const query = gql`
  query {
    someLocalField @client {
      name
    }
  }
`;

typegen.addons

It's optional. You can extend CLI's typegen command with this option.

For example, the following configuration loads my-addon.ts, which is an Addon to map URL custom GraphQL scalar field to TypeScript string type.

/* tsconfig.json */
{
  "compilerOptions": {
    "plugins": [
      {
        "name": "ts-graphql-plugin",
        "schema": "schema.graphql",
        "typegen": {
          "addons": [
            "./my-addon"
          ]
        }
      }
    ]
  }
}
/* my-addon.ts */

import ts from 'typescript';
import { TypeGenAddonFactory } from 'ts-graphql-plguin';

const addonFactory: TypeGenAddonFactory = () => ({
  customScalar({ scalarType }) {
    if (scalarType.name === 'URL') {
      return ts.factory.createKeywordTypeNode(ts.SyntaxKind.StringKeyword);
    }
  },
});

module.exports = addonFactory;

The addons property accepts an array of strings. And each string should point Node.js module which implements TypeGenAddonFactory interface. You can pass not only ".js" files but also ".ts" files.

If you learn how to create your Addon, see type generator customization guide for more details.

ts-graphql-plugin also provides built-in Addons. See also the Built-in Type Generator Addons section.

removeDuplicatedFragments

It's optional and default: true. By default, this plugin ignores duplicated fragment definitions such as:

const fragment = gql`
  fragment A on Query {
    id
  }
`;

const query = gql`
  ${fragment}
  query MyQuery {
    ...A
  }
  ${fragment}
  # Duplicated fragment interpolation
`;

This option affects all editor supporting functions, results of CLI commands and results of transformation.

If you set this option false, this plugin passes through query document without removing duplication.

Built-in Type Generator Addons

typed-query-document

This Addon requires graphql v15.4.0 or later. To enable this feature, configure as the following:

{
  "compilerOptions": {
    "plugins": [
      {
        "name": "ts-graphql-plugin",
        "tag": "gql",
        "schema": "schema.graphql",
        "typegen": {
          "addons": [
            "ts-graphql-plugin/addons/typed-query-document"
          ]
        }
      }
    ]
  }
}

When enabled generated files export a type based on TypedQueryDocumentNode from GraphQL. The type extends the standard DocumentNode AST type but also includes types for result data and variables as type arguments.

To use this feature you can apply a type assertion to gql template tag expressions that evaluate to a DocumentNode value.

For example:

const query = gql`
  query MyQuery($take: Int!) {
    recipes(take: $take) {
      id
      title
    }
  }
` as import('./__generated__/my-query.ts').MyQueryDocument;

With that type assertion in place result data and variable types will automatically flow through any function that accepts the TypedQueryDocumentNode type.

For example here is how you can write a wrapper for the useQuery function from Apollo Client:

import { gql, QueryHookOptions, QueryResult, useQuery } from '@apollo/client';
import { TypedQueryDocumentNode } from 'graphql';
function useTypedQuery<ResponseData, Variables>(
  query: TypedQueryDocumentNode<ResponseData, Variables>,
  options: QueryHookOptions<ResponseData, Variables>,
): QueryResult<ResponseData, Variables> {
  return useQuery(query, options);
}
// example usage
const { data } = useTypedQuery(query, { variables: { take: 100 } });
//      ^                                          ^
//      inferred type is `MyQuery`                 |
//                                                 |
//                                        inferred type is `MyQueryVariables`

The result is that generated types are associated with queries at the point where the query is defined instead of at the points where the query is executed.

webpack custom transformer

ts-graphql-plugin provides TypeScript custom transformer to static transform from query template strings to GraphQL AST. It's useful if you use https://github.com/apollographql/graphql-tag

/* webpack.config.js */
const TsGraphQLPlugin = require('ts-graphql-plugin/webpack');

const tsgqlPlugin = new TsGraphQLPlugin({
  /* plugin options */
});

module.exports = {
  module: {
    rules: [
      {
        test: /\.tsx?$/,
        exclude: /node_modules/,
        loader: 'ts-loader',
        options: {
          getCustomTransformers: () => ({
            before: [
              tsgqlPlugin.getTransformer({
                /* transformer options */
              }),
            ],
          }),
        },
      },
    ],
  },
  plugins: [tsgqlPlugin],
};

NOTE: For now, this plugin transforms nothing when webpack's --mode option is development and webpack runs with --watch option.

webpack plugin options

tsconfigPath optional

Set your project tsconfig json's file path. Default value: tsconfig.json.

Transformer options

removeFragmentDefinitions optional

Default: true. If set, the transformer transforms template strings which include only GraphQL fragment definitions to empty string literal.

For example, we finally does not need the GraphQL AST document of fragment. We need interpolated GraphQL query AST for query. So this transformer statically resolves ${fragment} interpolation and removes right-hand-side of the fragment variable.

const fragment = gql`
  fragment MyFragment on Query {
    hello
  }
`;

const query = gql`
  ${fragment}
  query MyQuery {
    ...MyFragment
  }
`;

documentTransformers optional

Default: []. You can set an array of GraphQL AST document visitor functions. The visitor functions should be compatible to https://graphql.org/graphql-js/language/#visit .

Template strings

This tool analyzes template string literals in .ts files such as:

const query = gql`
  query MyQuery = {
    viewer {
      id
      name
    }
  }
`;

NOTE

This tool cannot interpret queries containing too complex TypeScript expressions because it statically explores GraphQL queries.

/* It's ok */

const fragment = gql`
  fragment MyFragment on User {
    id
    name
  }
`;

const query = gql`
  ${fragment}
  query MyQuery {
    viewer {
      ...MyFragment
    }
  }
`;
/* Bad */

const query = gql`
  query MyQuery {
    ${someComplexFunction()}
  }
`;

Keep your queries static (see also https://blog.apollographql.com/5-benefits-of-static-graphql-queries-b7fa90b0b69a ).

Available editors

I've checked the operation with the following editors:

  • Visual Studio Code
  • Vim (with tsuquyomi)

And the following editor have TypeScript plugin with LanguageService so they're compatible with this plugin:

  • Emacs
  • Sublime text
  • Eclipse

GraphQL version compatibility

  • If you use graphql < 15.x, install ts-graphql-plugin@^1.x.x.

Contributing

See contribution guide.

License

This software is released under the MIT License, see LICENSE.txt.