feat(server): local dev server to return __typename

#115
maoosi · Apr 9, 2023 · 6090eb1 · 6090eb1
1 parent 12b1d3d
commit 6090eb1
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Showing 2 changed files with 42 additions and 9 deletions.
diff --git a/packages/server/src/index.ts b/packages/server/src/index.ts
@@ -15,6 +15,7 @@ import { Authorizations } from '../../client/src'
 import { queryObject } from './utils/useGraphqlFilter'
 import useLambdaIdentity from './utils/useLambdaIdentity'
 import useLambdaEvents from './utils/useLambdaEvents'
+import { addTypename } from './utils/useGraphqlTypename'
 
 declare global {
     // eslint-disable-next-line no-var, vars-on-top
@@ -67,6 +68,14 @@ export async function createServer({ defaultQuery, lambdaHandler, port, schema,
     if (!lambdaHandler?.main)
         throw new Error('Handler has no exported function "main".')
 
+    const yogaSchema = createSchema({
+        typeDefs: [
+            readFileSync(join(__dirname, 'gql/appsync-scalars.gql'), { encoding: 'utf-8' }),
+            readFileSync(join(__dirname, 'gql/appsync-directives.gql'), { encoding: 'utf-8' }),
+            schema,
+        ],
+    })
+
     const useLambdaFunction = (): Plugin => {
         return {
             async onExecute({ args }) {
@@ -168,13 +177,20 @@ export async function createServer({ defaultQuery, lambdaHandler, port, schema,
                                 }
                             })
 
+                            const queryDocument = gql`${events[0].info.selectionSetGraphQL}`
+
                             const filteredResults = queryObject(
-                                gql`${events[0].info.selectionSetGraphQL}`,
+                                queryDocument,
                                 lambdaResults,
                                 { includeMissingData: true },
                             )
 
-                            setResult({ data: filteredResults })
+                            const typedResults = await addTypename(
+                                yogaSchema,
+                                filteredResults,
+                            )
+
+                            setResult({ data: typedResults })
                         }
                     },
                 }
@@ -183,13 +199,7 @@ export async function createServer({ defaultQuery, lambdaHandler, port, schema,
     }
 
     const yoga = createYoga({
-        schema: createSchema({
-            typeDefs: [
-                readFileSync(join(__dirname, 'gql/appsync-scalars.gql'), { encoding: 'utf-8' }),
-                readFileSync(join(__dirname, 'gql/appsync-directives.gql'), { encoding: 'utf-8' }),
-                schema,
-            ],
-        }),
+        schema: yogaSchema,
         graphiql: {
             title: 'Prisma-AppSync',
             defaultQuery: defaultQuery ? prettier.format(defaultQuery, { parser: 'graphql' }) : undefined,

diff --git a/packages/server/src/utils/useGraphqlTypename.ts b/packages/server/src/utils/useGraphqlTypename.ts
@@ -0,0 +1,23 @@
+import type { GraphQLSchema } from 'graphql'
+import { _ } from '../../../client/src'
+
+// Function to add '__typename' values to the partial result object
+export async function addTypename(
+    schema: GraphQLSchema,
+    partialResultObject: Record<string, any>,
+) {
+    return await _.traverseNodes(partialResultObject, async (node) => {
+        if (node?.key === '__typename') {
+            const pathsWithoutArrays = node.path?.filter(p => typeof p === 'string')
+
+            let fields = schema.getQueryType()?.getFields()?.[pathsWithoutArrays?.[0]]
+
+            for (let index = 1; index < pathsWithoutArrays.length - 1; index++)
+                fields = fields?.type?.ofType?.getFields()?.[pathsWithoutArrays[index]]
+
+            if (fields?.type)
+                node.set(String(fields.type).replace(/[\])}[{(]/g, ''))
+        }
+    })
+}
+