feat(gatsby): Allow custom resolver context (#16359)

gatsbyjs · Aug 5, 2019 · 142b8ff · 142b8ff
1 parent 18b4e9a
commit 142b8ff
Show file tree

Hide file tree

Showing 11 changed files with 317 additions and 16 deletions.
diff --git a/packages/gatsby/src/bootstrap/__tests__/graphql-runner.js b/packages/gatsby/src/bootstrap/__tests__/graphql-runner.js
@@ -8,6 +8,7 @@ const createStore = (schema = {}) => {
     getState: () => {
       return {
         schema,
+        schemaCustomization: {},
       }
     },
   }

diff --git a/packages/gatsby/src/bootstrap/graphql-runner.js b/packages/gatsby/src/bootstrap/graphql-runner.js
@@ -4,13 +4,13 @@ const withResolverContext = require(`../schema/context`)
 const errorParser = require(`../query/error-parser`).default
 
 const createGraphqlRunner = (store, reporter) => (query, context = {}) => {
-  const schema = store.getState().schema
+  const { schema, schemaCustomization } = store.getState()
 
   return graphql(
     schema,
     query,
     context,
-    withResolverContext(context, schema),
+    withResolverContext(context, schema, schemaCustomization.context),
     context
   ).then(result => {
     if (result.errors) {

diff --git a/packages/gatsby/src/commands/develop.js b/packages/gatsby/src/commands/develop.js
@@ -155,11 +155,11 @@ async function startServer(program) {
   app.use(
     graphqlEndpoint,
     graphqlHTTP(() => {
-      const schema = store.getState().schema
+      const { schema, schemaCustomization } = store.getState()
       return {
         schema,
         graphiql: false,
-        context: withResolverContext({}, schema),
+        context: withResolverContext({}, schema, schemaCustomization.context),
         formatError(err) {
           return {
             ...formatError(err),

diff --git a/packages/gatsby/src/query/query-runner.js b/packages/gatsby/src/query/query-runner.js
@@ -24,14 +24,19 @@ type QueryJob = {
 
 // Run query
 module.exports = async (queryJob: QueryJob) => {
-  const { schema, program, webpackCompilationHash } = store.getState()
+  const {
+    schema,
+    schemaCustomization,
+    program,
+    webpackCompilationHash,
+  } = store.getState()
 
   const graphql = (query, context) =>
     graphqlFunction(
       schema,
       query,
       context,
-      withResolverContext(context, schema),
+      withResolverContext(context, schema, schemaCustomization.context),
       context
     )
 

diff --git a/packages/gatsby/src/redux/actions/restricted.js b/packages/gatsby/src/redux/actions/restricted.js
@@ -1,4 +1,5 @@
 // @flow
+const { camelCase } = require(`lodash`)
 const report = require(`gatsby-cli/lib/reporter`)
 
 import type { Plugin } from "./types"
@@ -261,6 +262,60 @@ actions.createFieldExtension = (
   }
 }
 
+/**
+ * Make functionality available on field resolver `context`
+ *
+ * @availableIn [createSchemaCustomization]
+ *
+ * @param {object} context Object to make available on `context`.
+ * When called from a plugin, the context value will be namespaced under
+ * the camel-cased plugin name without the "gatsby-" prefix
+ * @example
+ * const getHtml = md => remark().use(html).process(md)
+ * exports.createSchemaCustomization = ({ actions }) => {
+ *   actions.createResolverContext({ getHtml })
+ * }
+ * // The context value can then be accessed in any field resolver like this:
+ * exports.createSchemaCustomization = ({ actions }) => {
+ *   actions.createTypes(schema.buildObjectType({
+ *     name: 'Test',
+ *     interfaces: ['Node'],
+ *     fields: {
+ *       md: {
+ *         type: 'String!',
+ *         async resolve(source, args, context, info) {
+ *           const processed = await context.transformerRemark.getHtml(source.internal.contents)
+ *           return processed.contents
+ *         }
+ *       }
+ *     }
+ *   }))
+ * }
+ */
+actions.createResolverContext = (
+  context: object,
+  plugin: Plugin,
+  traceId?: string
+) => dispatch => {
+  if (!context || typeof context !== `object`) {
+    report.error(
+      `Expected context value passed to \`createResolverContext\` to be an object. Received "${context}".`
+    )
+  } else {
+    const { name } = plugin || {}
+    const payload =
+      !name || name === `default-site-plugin`
+        ? context
+        : { [camelCase(name.replace(/^gatsby-/, ``))]: context }
+    dispatch({
+      type: `CREATE_RESOLVER_CONTEXT`,
+      plugin,
+      traceId,
+      payload,
+    })
+  }
+}
+
 const withDeprecationWarning = (actionName, action, api, allowedIn) => (
   ...args
 ) => {
@@ -336,6 +391,9 @@ const availableActionsByAPI = mapAvailableActionsToAPIs({
     [ALLOWED_IN]: [`sourceNodes`, `createSchemaCustomization`],
     [DEPRECATED_IN]: [`onPreInit`, `onPreBootstrap`],
   },
+  createResolverContext: {
+    [ALLOWED_IN]: [`createSchemaCustomization`],
+  },
   addThirdPartySchema: {
     [ALLOWED_IN]: [`sourceNodes`, `createSchemaCustomization`],
     [DEPRECATED_IN]: [`onPreInit`, `onPreBootstrap`],

diff --git a/packages/gatsby/src/redux/prepare-nodes.js b/packages/gatsby/src/redux/prepare-nodes.js
@@ -22,12 +22,17 @@ const enhancedNodeCacheId = ({ node, args }) =>
 function awaitSiftField(fields, node, k) {
   const field = fields[k]
   if (field.resolve) {
-    const { schema } = store.getState()
-    return field.resolve(node, {}, withResolverContext({}, schema), {
-      fieldName: k,
-      schema,
-      returnType: field.type,
-    })
+    const { schema, schemaCustomization } = store.getState()
+    return field.resolve(
+      node,
+      {},
+      withResolverContext({}, schema, schemaCustomization.context),
+      {
+        fieldName: k,
+        schema,
+        returnType: field.type,
+      }
+    )
   } else if (node[k] !== undefined) {
     return node[k]
   }

diff --git a/packages/gatsby/src/redux/reducers/schema-customization.js b/packages/gatsby/src/redux/reducers/schema-customization.js
@@ -1,6 +1,7 @@
 module.exports = (
   state = {
     composer: null,
+    context: {},
     fieldExtensions: {},
     thirdPartySchemas: [],
     types: [],
@@ -48,9 +49,17 @@ module.exports = (
         fieldExtensions: { ...state.fieldExtensions, [name]: extension },
       }
     }
+    case `CREATE_RESOLVER_CONTEXT`: {
+      const context = action.payload
+      return {
+        ...state,
+        context: { ...state.context, ...context },
+      }
+    }
     case `DELETE_CACHE`:
       return {
         composer: null,
+        context: {},
         fieldExtensions: {},
         thirdPartySchemas: [],
         types: [],

diff --git a/packages/gatsby/src/schema/__tests__/connection-filter-on-linked-nodes.js b/packages/gatsby/src/schema/__tests__/connection-filter-on-linked-nodes.js
@@ -30,10 +30,15 @@ async function queryResult(nodes, query) {
   nodes.forEach(node => store.dispatch({ type: `CREATE_NODE`, payload: node }))
 
   await build({})
-  const { schema } = store.getState()
+  const { schema, schemaCustomization } = store.getState()
 
   const context = { path: `foo` }
-  return graphql(schema, query, undefined, withResolverContext(context))
+  return graphql(
+    schema,
+    query,
+    undefined,
+    withResolverContext(context, schema, schemaCustomization.context)
+  )
 }
 
 describe(`filtering on linked nodes`, () => {