Merge pull request #584 from sundersc/generate-default-index-name

fix(codegen): generate default name for index directive

Author: sundersc

packages/appsync-modelgen-plugin/src/__tests__/utils/process-index.test.ts

@@ -132,6 +132,134 @@ describe('processIndex', () => {
     ]);
   });
 
+  it('should generate a default name to @index directive', () => {
+    const model: CodeGenModel = {
+      directives: [
+        {
+          name: 'model',
+          arguments: {},
+        },
+      ],
+      name: 'testModel',
+      type: 'model',
+      fields: [
+        {
+          type: 'field',
+          isList: false,
+          isNullable: true,
+          name: 'connectionField',
+          directives: [
+            {
+              name: 'index',
+              arguments: {},
+            },
+          ],
+        },
+        {
+          type: 'field',
+          isList: false,
+          isNullable: true,
+          name: 'anotherConnection',
+          directives: [
+            {
+              name: 'index',
+              arguments: {},
+            },
+          ],
+        },
+      ],
+    };
+    processIndex(model);
+    expect(model.directives).toEqual([
+      {
+        name: 'model',
+        arguments: {},
+      },
+      {
+        name: 'key',
+        arguments: {
+          name: 'testModelsByConnectionField',
+          fields: ['connectionField'],
+          queryField: undefined,
+        },
+      },
+      {
+        name: 'key',
+        arguments: {
+          name: 'testModelsByAnotherConnection',
+          fields: ['anotherConnection'],
+          queryField: undefined,
+        },
+      },
+    ]);
+  });
+
+  it('should generate a default name to @index directive with sortkeys', () => {
+    const model: CodeGenModel = {
+      directives: [
+        {
+          name: 'model',
+          arguments: {},
+        },
+      ],
+      name: 'testModel',
+      type: 'model',
+      fields: [
+        {
+          type: 'field',
+          isList: false,
+          isNullable: true,
+          name: 'connectionField',
+          directives: [
+            {
+              name: 'index',
+              arguments: {
+                sortKeyFields: ['sortField'],
+              },
+            },
+          ],
+        },
+        {
+          type: 'field',
+          isList: false,
+          isNullable: true,
+          name: 'anotherConnection',
+          directives: [
+            {
+              name: 'index',
+              arguments: {
+                sortKeyFields: ['sortField1', 'sortField2'],
+              },
+            },
+          ],
+        },
+      ],
+    };
+    processIndex(model);
+    expect(model.directives).toEqual([
+      {
+        name: 'model',
+        arguments: {},
+      },
+      {
+        name: 'key',
+        arguments: {
+          name: 'testModelsByConnectionFieldAndSortField',
+          fields: ['connectionField', 'sortField'],
+          queryField: undefined, 
+        },
+      },
+      {
+        name: 'key',
+        arguments: {
+          name: 'testModelsByAnotherConnectionAndSortField1AndSortField2',
+          fields: ['anotherConnection', 'sortField1', 'sortField2'],
+          queryField: undefined,
+        },
+      },
+    ]);
+  });
+
   it('does nothing if no @index directives in model', () => {
     const model: CodeGenModel = {
       directives: [

packages/appsync-modelgen-plugin/src/utils/process-index.ts

@@ -1,5 +1,7 @@
 import { CodeGenDirective, CodeGenModel } from '../visitors/appsync-visitor';
 import { getDirective } from './fieldUtils';
+import pluralize from 'pluralize';
+import { toLower, toUpper } from './stringUtils';
 
 /**
  * Maps @index directives back to how they would be represented with the old @key directive
@@ -17,7 +19,7 @@ export const processIndex = (model: CodeGenModel) => {
   const keyList: CodeGenDirective[] = Object.entries(indexMap).map(([fieldName, directive]) => ({
     name: 'key',
     arguments: {
-      name: directive.arguments.name,
+      name: directive.arguments.name ?? generateDefaultIndexName(model.name, [fieldName].concat((directive.arguments.sortKeyFields as string[]) ?? [])),
       queryField: directive.arguments.queryField,
       fields: [fieldName].concat((directive.arguments.sortKeyFields as string[]) ?? []),
     },
@@ -28,3 +30,14 @@ export const processIndex = (model: CodeGenModel) => {
   const deDupedKeyList = keyList.filter(key => !existingIndexNames.includes(key.arguments.name));
   model.directives.push(...deDupedKeyList);
 };
+
+/*
+ * Accepts a model and field name, and potentially empty list of sortKeyFields to generate a unique index name.
+ * e.g. modelName = Employee, fieldName = manager, sortKeyFields = [level]
+ * will generate a name like employeesByManagerAndLevel.
+ * (This naming logic is used to generate a default index name for @index directives that don't have a name argument).
+ * Refer https://github.com/aws-amplify/amplify-category-api/blob/main/packages/amplify-graphql-index-transformer/src/utils.ts
+ */
+export const generateDefaultIndexName = (modelName: string, fieldNames: string[]): string => {
+  return `${toLower(pluralize(modelName))}By${fieldNames.map(toUpper).join('And')}`;
+};

packages/appsync-modelgen-plugin/src/utils/stringUtils.ts

@@ -0,0 +1,7 @@
+export function toUpper(word: string): string {
+  return word.charAt(0).toUpperCase() + word.slice(1);
+}
+
+export function toLower(word: string): string {
+  return word.charAt(0).toLowerCase() + word.slice(1);
+}