feat(gatsby): Improvements to GraphQL TypeScript Generation

e2e-tests/development-runtime/cypress/integration/graphql-typegen/files-existence.js

@@ -0,0 +1,76 @@
+// https://docs.cypress.io/api/commands/readfile#Existence
+// By default, cy.readFile() asserts that the file exists and will fail if it does not exist.
+
+const FRAGMENT = `fragment TestingFragment on Site {
+  siteMetadata {
+    author
+  }
+}`
+
+const GRAPHQL_TYPE = `type CheckMePlease {
+  hello: String!
+}`
+
+const TS_TYPE = `type CheckMePlease = {
+  readonly hello: Scalars['String'];
+};`
+
+describe(`typecheck`, () => {
+  it(`passes without an error`, () => {
+    cy.exec(`npm run typecheck`)
+  })
+})
+
+describe('fragments.graphql', () => {
+  it('exists in .cache folder', () => {
+    cy.readFile('.cache/typegen/fragments.graphql')
+  })
+  it('contains test fragment', () => {
+    cy.readFile('.cache/typegen/fragments.graphql').then((file) => {
+      expect(file).to.include(FRAGMENT)
+    })
+  })
+})
+
+describe('graphql-config', () => {
+  it('exists in .cache folder with correct data', () => {
+    cy.readFile('.cache/typegen/graphql.config.json', 'utf-8').then((json) => {
+      expect(json).to.deep.equal({
+        "schema": ".cache/typegen/schema.graphql",
+        "documents": [
+          "src/**/**.{ts,js,tsx,jsx}",
+          ".cache/typegen/fragments.graphql"
+        ],
+        "extensions": {
+          "endpoints": {
+            "default": {
+              "url": "http://localhost:8000/___graphql"
+            }
+          }
+        }
+      })
+    })
+  })
+})
+
+describe('schema.graphql', () => {
+  it('exists in .cache folder', () => {
+    cy.readFile('.cache/typegen/schema.graphql')
+  })
+  it('contains test type', () => {
+    cy.readFile('.cache/typegen/schema.graphql').then((file) => {
+      expect(file).to.include(GRAPHQL_TYPE)
+    })
+  })
+})
+
+describe('gatsby-types.d.ts', () => {
+  it('exists in src folder', () => {
+    cy.readFile('src/gatsby-types.d.ts')
+  })
+  it('contains test type', () => {
+    cy.readFile('src/gatsby-types.d.ts').then((file) => {
+      expect(file).to.include(TS_TYPE)
+    })
+  })
+})

e2e-tests/development-runtime/cypress/integration/graphql-typegen/updates.js

@@ -0,0 +1,56 @@
+const QUERY_BEFORE = `type GraphQLTypegenQuery = { readonly site: { readonly siteMetadata: { readonly title: string | null } | null } | null };`
+const QUERY_AFTER = `type GraphQLTypegenQuery = { readonly site: { readonly siteMetadata: { readonly author: string | null, readonly title: string | null } | null } | null };`
+const FRAGMENT_BEFORE = `fragment SiteInformation on Site {
+  buildTime
+}`
+const FRAGMENT_AFTER = `fragment SiteInformation on Site {
+  buildTime
+  trailingSlash
+}`
+
+beforeEach(() => {
+  cy.visit(`/graphql-typegen/`).waitForRouteChange()
+})
+
+after(() => {
+  cy.exec(`npm run reset`)
+})
+
+describe(`hot-reloading changes on GraphQL Typegen files`, () => {
+  it(`contains initial contents in files`, () => {
+    cy.readFile('src/gatsby-types.d.ts').then((file) => {
+      expect(file).to.include(QUERY_BEFORE)
+    })
+    cy.readFile('.cache/typegen/fragments.graphql').then((file) => {
+      expect(file).to.include(FRAGMENT_BEFORE)
+    })
+  })
+
+  it(`can edit a page query`, () => {
+    cy.exec(
+      `npm run update -- --file src/pages/graphql-typegen.tsx --replacements "# %AUTHOR%:author" --exact`
+    )
+
+    cy.waitForHmr()
+
+    cy.readFile('src/gatsby-types.d.ts').then((file) => {
+      expect(file).to.include(QUERY_AFTER)
+    })
+  })
+
+  it(`can edit a fragment`, () => {
+    cy.exec(
+      `npm run update -- --file src/pages/graphql-typegen.tsx --replacements "# %TRAILING_SLASH%:trailingSlash" --exact`
+    )
+
+    cy.waitForHmr()
+
+    cy.readFile('.cache/typegen/fragments.graphql').then((file) => {
+      expect(file).to.include(FRAGMENT_AFTER)
+    })
+  })
+
+  it(`successfully runs typecheck`, () => {
+    cy.exec(`npm run typecheck`)
+  })
+})

e2e-tests/development-runtime/gatsby-config.js

@@ -30,6 +30,7 @@ module.exports = {
     `gatsby-source-pinc-data`,
     `gatsby-source-query-on-demand-data`,
     `gatsby-browser-tsx`,
+    `gatsby-node-typegen`,
     `gatsby-transformer-sharp`,
     `gatsby-transformer-json`,
     {

e2e-tests/development-runtime/package.json

@@ -38,6 +38,7 @@
     "develop": "cross-env CYPRESS_SUPPORT=y ENABLE_GATSBY_REFRESH_ENDPOINT=true GATSBY_EXPERIMENTAL_QUERY_ON_DEMAND=y GATSBY_GRAPHQL_TYPEGEN=y gatsby develop",
     "serve": "gatsby serve",
     "clean": "gatsby clean",
+    "typecheck": "tsc --noEmit",
     "start": "npm run develop",
     "format": "prettier --write \"src/**/*.js\"",
     "test": "npm run start-server-and-test || (npm run reset && exit 1)",
@@ -64,6 +65,7 @@
     "is-ci": "^2.0.0",
     "prettier": "2.0.4",
     "start-server-and-test": "^1.7.11",
+    "typescript": "^4.6.4",
     "yargs": "^12.0.5"
   },
   "repository": {

e2e-tests/development-runtime/plugins/gatsby-node-typegen/gatsby-node.ts

@@ -0,0 +1,23 @@
+import { GatsbyNode } from "gatsby"
+
+export const createSchemaCustomization: GatsbyNode["createSchemaCustomization"] = ({ actions }) => {
+  const { createTypes } = actions
+
+  createTypes(`
+    type CheckMePlease {
+      hello: String!
+    }
+  `)
+}
+
+export const createPages: GatsbyNode["createPages"] = async ({ graphql }) => {
+  await graphql<Queries.GatsbyNodeQuery>(`#graphql
+    query GatsbyNode {
+      site {
+        siteMetadata {
+          title
+        }
+      }
+    }
+  `)
+}

e2e-tests/development-runtime/plugins/gatsby-node-typegen/package.json

@@ -0,0 +1 @@
+{}

e2e-tests/development-runtime/src/pages/graphql-typegen.tsx

@@ -0,0 +1,27 @@
+import React from "react"
+import { graphql, PageProps } from "gatsby"
+
+function GraphQLTypegen({ data }: PageProps<Queries.GraphQLTypegenQuery>) {
+  return (
+    <p>
+      {data?.site?.siteMetadata?.title}
+    </p>
+  )
+}
+
+export const query = graphql`
+  query GraphQLTypegen{
+    site {
+      siteMetadata {
+        # %AUTHOR%
+        title
+      }
+    }
+  }
+  fragment SiteInformation on Site {
+    buildTime
+    # %TRAILING_SLASH%
+  }
+`
+
+export default GraphQLTypegen

e2e-tests/development-runtime/tsconfig.json

@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "target": "esnext",
+    "lib": ["dom", "esnext"],
+    "jsx": "react",
+    "module": "esnext",
+    "moduleResolution": "node",
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "strict": true,
+    "skipLibCheck": true
+  },
+  "include": ["./src/**/*", "./plugins/**/*"]
+}

packages/gatsby/src/services/graphql-typegen.ts

@@ -1,34 +1,21 @@
-import { EventObject } from "xstate"
 import { IBuildContext } from "../internal"
-import { IDataLayerContext, IQueryRunningContext } from "../state-machines"
 import {
   writeGraphQLFragments,
   writeGraphQLSchema,
 } from "../utils/graphql-typegen/file-writes"
 import { writeTypeScriptTypes } from "../utils/graphql-typegen/ts-codegen"
 
-export async function graphQLTypegen(
-  {
-    program,
-    store,
-    parentSpan,
-    reporter,
-  }: IBuildContext | IQueryRunningContext | IDataLayerContext,
-  _: EventObject,
-  {
-    src: { compile },
-  }: {
-    src: {
-      type: string
-      compile?: "all" | "schema" | "definitions"
-    }
-  }
-): Promise<void> {
+export async function graphQLTypegen({
+  program,
+  store,
+  parentSpan,
+  reporter,
+}: IBuildContext): Promise<void> {
   // TypeScript requires null/undefined checks for these
   // But this should never happen unless e.g. the state machine doesn't receive this information from a parent state machine
-  if (!program || !store || !compile || !reporter) {
+  if (!program || !store || !reporter) {
     throw new Error(
-      `Missing required params in graphQLTypegen. program: ${!!program}. store: ${!!store}. compile: ${!!compile}`
+      `Missing required params in graphQLTypegen. program: ${!!program}. store: ${!!store}.`
     )
   }
   const directory = program.directory
@@ -41,19 +28,11 @@ export async function graphQLTypegen(
   )
   activity.start()
 
-  if (compile === `all` || compile === `schema`) {
-    await writeGraphQLSchema(directory, store)
-    if (compile === `schema`) {
-      reporter.verbose(`Re-Generate GraphQL Schema types`)
-    }
-  }
-  if (compile === `all` || compile === `definitions`) {
-    await writeGraphQLFragments(directory, store)
-    await writeTypeScriptTypes(directory, store)
-    if (compile === `definitions`) {
-      reporter.verbose(`Re-Generate TypeScript types & GraphQL fragments`)
-    }
-  }
+  const { schema, definitions } = store.getState()
+
+  await writeGraphQLSchema(directory, schema)
+  await writeGraphQLFragments(directory, definitions)
+  await writeTypeScriptTypes(directory, schema, definitions)
 
   activity.end()
 }

packages/gatsby/src/services/listen-for-mutations.ts

@@ -18,15 +18,27 @@ export const listenForMutations: InvokeCallback = (callback: Sender<any>) => {
     callback({ type: `QUERY_RUN_REQUESTED`, payload: event })
   }
 
+  const emitSetSchema = (event: unknown): void => {
+    callback({ type: `SET_SCHEMA`, payload: event })
+  }
+
+  const emitGraphQLDefinitions = (event: unknown): void => {
+    callback({ type: `SET_GRAPHQL_DEFINITIONS`, payload: event })
+  }
+
   emitter.on(`ENQUEUE_NODE_MUTATION`, emitMutation)
   emitter.on(`WEBHOOK_RECEIVED`, emitWebhook)
   emitter.on(`SOURCE_FILE_CHANGED`, emitSourceChange)
   emitter.on(`QUERY_RUN_REQUESTED`, emitQueryRunRequest)
+  emitter.on(`SET_SCHEMA`, emitSetSchema)
+  emitter.on(`SET_GRAPHQL_DEFINITIONS`, emitGraphQLDefinitions)
 
   return function unsubscribeFromMutationListening(): void {
     emitter.off(`ENQUEUE_NODE_MUTATION`, emitMutation)
     emitter.off(`WEBHOOK_RECEIVED`, emitWebhook)
     emitter.off(`SOURCE_FILE_CHANGED`, emitSourceChange)
     emitter.off(`QUERY_RUN_REQUESTED`, emitQueryRunRequest)
+    emitter.off(`SET_SCHEMA`, emitSetSchema)
+    emitter.off(`SET_GRAPHQL_DEFINITIONS`, emitGraphQLDefinitions)
   }
 }

packages/gatsby/src/state-machines/data-layer/index.ts

@@ -69,26 +69,9 @@ const recreatePagesStates: StatesConfig<IDataLayerContext, any, any> = {
     invoke: {
       id: `building-schema`,
       src: `buildSchema`,
-      onDone: [
-        {
-          target: `graphQLTypegen`,
-          cond: (): boolean => !!process.env.GATSBY_GRAPHQL_TYPEGEN,
-        },
-        {
-          target: `creatingPages`,
-        },
-      ],
-    },
-    exit: `assignGraphQLRunners`,
-  },
-  graphQLTypegen: {
-    invoke: {
-      src: {
-        type: `graphQLTypegen`,
-        compile: `schema`,
-      },
       onDone: {
         target: `creatingPages`,
+        actions: `assignGraphQLRunners`,
       },
     },
   },