feat(gatsby): Add option to emit TS types during build

docs/docs/how-to/local-development/graphql-typegen.md

@@ -9,7 +9,7 @@ examples:
 
 If you're already using [Gatsby with TypeScript](/docs/how-to/custom-configuration/typescript) and manually typing the results of your queries, you'll learn in this guide how Gatsby's automatic GraphQL Typegen feature can make your life easier. By relying on the types that are generated by Gatsby itself and using autocompletion for GraphQL queries in your IDE you'll be able to write GraphQL queries quicker and safer.
 
-This feature was added in `gatsby@4.15.0`.
+This feature was added in `gatsby@4.15.0`. By default, this feature is only generating files during `gatsby develop`.
 
 ## Prerequisites
 

docs/docs/reference/config-files/gatsby-config.md

@@ -206,6 +206,10 @@ module.exports = {
 
 You can specifiy the path of the generated TypeScript types file relative to the site root. Default: `src/gatsby-types.d.ts`.
 
+### generateOnBuild
+
+By default, `graphqlTypegen` is only run during `gatsby develop`. Set this option to `true` to create the `src/gatsby-types.d.ts` file also during `gatsby build`. Default: `false`.
+
 ## polyfill
 
 Gatsby uses the ES6 Promise API. Because some browsers don't support this, Gatsby includes a Promise polyfill by default.

packages/gatsby/index.d.ts

@@ -258,6 +258,7 @@ export const graphql: (query: TemplateStringsArray) => StaticQueryDocument
 
 export interface GraphQLTypegenOptions {
   typesOutputPath?: string
+  generateOnBuild?: boolean
 }
 
 /**

packages/gatsby/src/commands/build.ts

@@ -63,6 +63,7 @@ import {
 import { validateEngines } from "../utils/validate-engines"
 import { constructConfigObject } from "../utils/gatsby-cloud-config"
 import { waitUntilWorkerJobsAreComplete } from "../utils/jobs/worker-messaging"
+import { writeTypeScriptTypes } from "../utils/graphql-typegen/ts-codegen"
 
 module.exports = async function build(
   program: IBuildArgs,
@@ -419,6 +420,42 @@ module.exports = async function build(
   await waitMaterializePageMode
   const waitWorkerPoolEnd = Promise.all(workerPool.end())
 
+  // create scope so we don't leak state object
+  {
+    const { schema, definitions, config } = store.getState()
+    const directory = program.directory
+    const graphqlTypegenOptions = config.graphqlTypegen
+
+    // Only generate types when the option is enabled
+    if (graphqlTypegenOptions && graphqlTypegenOptions.generateOnBuild) {
+      const typegenActivity = reporter.activityTimer(
+        `Generating TypeScript types`,
+        {
+          parentSpan: buildSpan,
+        }
+      )
+      typegenActivity.start()
+
+      try {
+        await writeTypeScriptTypes(
+          directory,
+          schema,
+          definitions,
+          graphqlTypegenOptions
+        )
+      } catch (err) {
+        typegenActivity.panicOnBuild({
+          id: `12100`,
+          context: {
+            sourceMessage: err,
+          },
+        })
+      }
+
+      typegenActivity.end()
+    }
+  }
+
   {
     let SSGCount = 0
     let DSGCount = 0

packages/gatsby/src/joi-schemas/__tests__/joi.ts

@@ -186,6 +186,7 @@ describe(`gatsby config`, () => {
       expect.objectContaining({
         graphqlTypegen: {
           typesOutputPath: `src/gatsby-types.d.ts`,
+          generateOnBuild: false,
         },
       })
     )
@@ -201,12 +202,12 @@ describe(`gatsby config`, () => {
       expect.objectContaining({
         graphqlTypegen: {
           typesOutputPath: `src/gatsby-types.d.ts`,
+          generateOnBuild: false,
         },
       })
     )
   })
 
-  // TODO: Write "return partial defaults for graphqlTypegen when partial options object is set" test with more graphqlTypegen options
   it(`graphqlTypegen config object can be overwritten`, () => {
     const config = {
       graphqlTypegen: {
@@ -219,6 +220,25 @@ describe(`gatsby config`, () => {
       expect.objectContaining({
         graphqlTypegen: {
           typesOutputPath: `gatsby-types.d.ts`,
+          generateOnBuild: false,
+        },
+      })
+    )
+  })
+
+  it(`returns partial defaults for graphqlTypegen when partial options object is set`, () => {
+    const config = {
+      graphqlTypegen: {
+        generateOnBuild: true,
+      },
+    }
+
+    const result = gatsbyConfigSchema.validate(config)
+    expect(result.value).toEqual(
+      expect.objectContaining({
+        graphqlTypegen: {
+          typesOutputPath: `src/gatsby-types.d.ts`,
+          generateOnBuild: true,
         },
       })
     )

packages/gatsby/src/joi-schemas/joi.ts

@@ -61,6 +61,7 @@ export const gatsbyConfigSchema: Joi.ObjectSchema<IGatsbyConfig> = Joi.object()
       Joi.object()
         .keys({
           typesOutputPath: Joi.string().default(DEFAULT_TYPES_OUTPUT_PATH),
+          generateOnBuild: Joi.boolean().default(false),
         })
         .unknown(false)
     )
@@ -69,6 +70,7 @@ export const gatsbyConfigSchema: Joi.ObjectSchema<IGatsbyConfig> = Joi.object()
         if (value === true) {
           return {
             typesOutputPath: DEFAULT_TYPES_OUTPUT_PATH,
+            generateOnBuild: false,
           }
         }
 

packages/gatsby/src/redux/types.ts

@@ -80,6 +80,7 @@ export interface IGatsbyFunction {
 
 export interface IGraphQLTypegenOptions {
   typesOutputPath: string
+  generateOnBuild: boolean
 }
 
 export interface IGatsbyConfig {

packages/gatsby/src/services/initialize.ts

@@ -659,10 +659,12 @@ export async function initialize({
 
   const workerPool = WorkerPool.create()
 
-  // This is only run during `gatsby develop`
   if (state.config.graphqlTypegen) {
     telemetry.trackFeatureIsUsed(`GraphQLTypegen`)
-    writeGraphQLConfig(program)
+    // This is only run during `gatsby develop`
+    if (process.env.gatsby_executing_command === `develop`) {
+      writeGraphQLConfig(program)
+    }
   }
 
   return {