feat(openapi): support links on non-object fields (#4376)

* feat(openapi): support links on non-object fields

* Fix TS

Author: ardatan

.changeset/famous-games-arrive.md

@@ -0,0 +1,6 @@
+---
+"@omnigraph/json-schema": minor
+"@omnigraph/openapi": minor
+---
+
+Support links on non-object fields

packages/loaders/json-schema/src/addExecutionLogicToComposer.ts

@@ -497,19 +497,32 @@ ${operationConfig.description || ''}
           const responseConfig = operationConfig.responseByStatusCode[statusCode];
           if (responseConfig.links || responseConfig.exposeResponseMetadata) {
             const typeTCThunked = types[statusCodeOneOfIndexMap[statusCode] || 0];
-            const typeTC = schemaComposer.getAnyTC(typeTCThunked.getTypeName());
-            if ('addFieldArgs' in typeTC) {
-              if (responseConfig.exposeResponseMetadata) {
-                typeTC.addFields({
-                  _response: {
-                    type: responseMetadataType,
-                    resolve: root => root.$response,
+            const originalName = typeTCThunked.getTypeName();
+            let typeTC = schemaComposer.getAnyTC(originalName);
+            if (!('addFieldArgs' in typeTC)) {
+              typeTC = schemaComposer.createObjectTC({
+                name: `${operationConfig.field}_${statusCode}_response`,
+                fields: {
+                  [originalName]: {
+                    type: typeTC as any,
+                    resolve: root => root,
                   },
-                });
-              }
-              if (responseConfig.links) {
-                handleLinkMap(responseConfig.links, typeTC as ObjectTypeComposer);
-              }
+                },
+              });
+              // If it is a scalar or enum type, it cannot be a union type, so we can set it directly
+              types[0] = typeTC;
+              field.type = typeTC;
+            }
+            if (responseConfig.exposeResponseMetadata) {
+              typeTC.addFields({
+                _response: {
+                  type: responseMetadataType,
+                  resolve: root => root.$response,
+                },
+              });
+            }
+            if (responseConfig.links) {
+              handleLinkMap(responseConfig.links, typeTC as ObjectTypeComposer);
             }
           }
         }

packages/loaders/json-schema/src/getUnionTypeComposers.ts

@@ -3,6 +3,7 @@ import { JSONSchemaObject } from '@json-schema-tools/meta-schema';
 import Ajv from 'ajv';
 import {
   AnyTypeComposer,
+  ComposeInputType,
   InputTypeComposer,
   isSomeInputTypeComposer,
   ObjectTypeComposer,
@@ -24,6 +25,18 @@ export interface GetUnionTypeComposersOpts {
   logger: Logger;
 }
 
+export function getContainerTC(schemaComposer: SchemaComposer, output: ComposeInputType) {
+  const containerTypeName = `${output.getTypeName()}_container`;
+  return schemaComposer.getOrCreateOTC(containerTypeName, otc =>
+    otc.addFields({
+      [output.getTypeName()]: {
+        type: output as any,
+        resolve: root => root,
+      },
+    })
+  );
+}
+
 export function getUnionTypeComposers({
   schemaComposer,
   ajv,
@@ -39,17 +52,7 @@ export function getUnionTypeComposers({
   typeComposersList.forEach(typeComposers => {
     const { input, output } = typeComposers;
     if (isSomeInputTypeComposer(output)) {
-      const containerTypeName = `${output.getTypeName()}_container`;
-      outputTypeComposers.push(
-        schemaComposer.getOrCreateOTC(containerTypeName, otc =>
-          otc.addFields({
-            [output.getTypeName()]: {
-              type: output,
-              resolve: root => root,
-            },
-          })
-        )
-      );
+      outputTypeComposers.push(getContainerTC(schemaComposer, output));
     } else {
       outputTypeComposers.push(output);
     }

packages/loaders/openapi/tests/__snapshots__/non_string_links.test.ts.snap

@@ -0,0 +1,21 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Links on non-object fields should generate the correct schema 1`] = `
+"schema {
+  query: Query
+}
+
+type Query {
+  test: test_200_response
+  testLink: testLink_200_response
+}
+
+type test_200_response {
+  String: String
+  testLink: testLink_200_response
+}
+
+type testLink_200_response {
+  foo: String
+}"
+`;

packages/loaders/openapi/tests/fixtures/non_string_links.yml

@@ -0,0 +1,38 @@
+openapi: 3.0.1
+info:
+  title: API
+  description: ''
+  contact: {}
+  version: '1.0'
+servers:
+  - url: http://localhost:7777
+security:
+  - ApiKeyAuth: []
+tags: []
+paths:
+  /test:
+    get:
+      operationId: test
+      responses:
+        200:
+          description: ''
+          content:
+            application/json:
+              schema:
+                type: string
+          links:
+            testLink:
+              operationId: testLink
+  /test-link:
+    get:
+      operationId: testLink
+      responses:
+        200:
+          description: ''
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  foo:
+                    type: string

packages/loaders/openapi/tests/non_string_links.test.ts

@@ -0,0 +1,12 @@
+import { printSchemaWithDirectives } from '@graphql-tools/utils';
+import loadGraphQLSchemaFromOpenAPI from '../src';
+
+describe('Links on non-object fields', () => {
+  it('should generate the correct schema', async () => {
+    const schema = await loadGraphQLSchemaFromOpenAPI('toto', {
+      source: './fixtures/non_string_links.yml',
+      cwd: __dirname,
+    });
+    expect(printSchemaWithDirectives(schema)).toMatchSnapshot();
+  });
+});