fix(api): GraphQL Model Helpers support lowercase model names

packages/api/amplify_api/example/amplify/backend/api/apiintegmultiauth/schema.graphql

@@ -67,3 +67,18 @@ type OwnerOnly @model @auth(rules: [{allow: owner}]) {
   id: ID!
   name: String!
 } 
+
+type lowerCase
+  @model
+  @auth(
+    rules: [
+      { allow: public, operations: [read], provider: apiKey },
+      { allow: public, operations: [read], provider: iam },
+      { allow: private, operations: [read], provider: iam },
+      { allow: private, operations: [read], provider: userPools },
+      { allow: owner, operations: [create, read, update, delete] }
+    ]
+  ) {
+  id: ID!
+  name: String!
+}

packages/api/amplify_api/example/integration_test/graphql/user_pools_test.dart

@@ -122,6 +122,24 @@ void main({bool useExistingTestUser = false}) {
         expect(data.rating, equals(rating));
       });
 
+      testWidgets('should CREATE a lower case model name with Model helper',
+          (WidgetTester tester) async {
+        final name = 'Integration Test lowercase - ${uuid()}';
+        final model = lowerCase(name: name);
+
+        final req = ModelMutations.create(
+          model,
+          authorizationMode: APIAuthorizationType.userPools,
+        );
+        final res = await Amplify.API.mutate(request: req).response;
+        expect(res, hasNoGraphQLErrors);
+        final data = res.data;
+        if (data != null) lowerCaseCache.add(data);
+
+        expect(data?.name, equals(model.name));
+        expect(data?.id, equals(model.id));
+      });
+
       testWidgets('should UPDATE a blog with Model helper',
           (WidgetTester tester) async {
         const oldName = 'Integration Test Blog to update';

packages/api/amplify_api/example/integration_test/util.dart

@@ -19,6 +19,7 @@ TestUser? testUser;
 final blogCache = <Blog>[];
 final postCache = <Post>[];
 final ownerOnlyCache = <OwnerOnly>[];
+final lowerCaseCache = <lowerCase>[];
 final cpkParentCache = <CpkOneToOneBidirectionalParentCD>[];
 final cpkExplicitChildCache = <CpkOneToOneBidirectionalChildExplicitCD>[];
 final cpkImplicitChildCache = <CpkOneToOneBidirectionalChildImplicitCD>[];
@@ -297,12 +298,25 @@ Future<OwnerOnly?> deleteOwnerOnly(OwnerOnly model) async {
   return res.data;
 }
 
+Future<lowerCase?> deleteLowerCase(lowerCase model) async {
+  final request = ModelMutations.deleteById(
+    lowerCase.classType,
+    model.modelIdentifier,
+    authorizationMode: APIAuthorizationType.userPools,
+  );
+  final res = await Amplify.API.mutate(request: request).response;
+  expect(res, hasNoGraphQLErrors);
+  lowerCaseCache.removeWhere((modelFromCache) => modelFromCache.id == model.id);
+  return res.data;
+}
+
 Future<void> deleteTestModels() async {
   await Future.wait(blogCache.map(deleteBlog));
   await Future.wait(postCache.map(deletePost));
   await Future.wait(cpkExplicitChildCache.map(deleteCpkExplicitChild));
   await Future.wait(cpkImplicitChildCache.map(deleteCpkImplicitChild));
   await Future.wait(ownerOnlyCache.map(deleteOwnerOnly));
+  await Future.wait(lowerCaseCache.map(deleteLowerCase));
 }
 
 /// Wait for subscription established for given request.

packages/api/amplify_api/example/lib/models/Blog.dart

@@ -20,19 +20,17 @@
 // ignore_for_file: public_member_api_docs, annotate_overrides, dead_code, dead_codepublic_member_api_docs, depend_on_referenced_packages, file_names, library_private_types_in_public_api, no_leading_underscores_for_library_prefixes, no_leading_underscores_for_local_identifiers, non_constant_identifier_names, null_check_on_nullable_type_parameter, prefer_adjacent_string_concatenation, prefer_const_constructors, prefer_if_null_operators, prefer_interpolation_to_compose_strings, slash_for_doc_comments, sort_child_properties_last, unnecessary_const, unnecessary_constructor_name, unnecessary_late, unnecessary_new, unnecessary_null_aware_assignments, unnecessary_nullable_for_final_variable_declarations, unnecessary_string_interpolations, use_build_context_synchronously
 
 import 'ModelProvider.dart';
-import 'package:amplify_core/amplify_core.dart';
+import 'package:amplify_core/amplify_core.dart' as amplify_core;
 import 'package:collection/collection.dart';
-import 'package:flutter/foundation.dart';
 
-/// This is an auto generated class representing the Blog type in your schema.
-@immutable
-class Blog extends Model {
-  static const classType = _BlogModelType();
+/** This is an auto generated class representing the Blog type in your schema. */
+class Blog extends amplify_core.Model {
+  static const classType = const _BlogModelType();
   final String id;
   final String? _name;
   final List<Post>? _posts;
-  final TemporalDateTime? _createdAt;
-  final TemporalDateTime? _updatedAt;
+  final amplify_core.TemporalDateTime? _createdAt;
+  final amplify_core.TemporalDateTime? _updatedAt;
 
   @override
   getInstanceType() => classType;
@@ -50,10 +48,10 @@ class Blog extends Model {
     try {
       return _name!;
     } catch (e) {
-      throw AmplifyCodeGenModelException(
-          AmplifyExceptionMessages
+      throw amplify_core.AmplifyCodeGenModelException(
+          amplify_core.AmplifyExceptionMessages
               .codeGenRequiredFieldForceCastExceptionMessage,
-          recoverySuggestion: AmplifyExceptionMessages
+          recoverySuggestion: amplify_core.AmplifyExceptionMessages
               .codeGenRequiredFieldForceCastRecoverySuggestion,
           underlyingException: e.toString());
     }
@@ -63,11 +61,11 @@ class Blog extends Model {
     return _posts;
   }
 
-  TemporalDateTime? get createdAt {
+  amplify_core.TemporalDateTime? get createdAt {
     return _createdAt;
   }
 
-  TemporalDateTime? get updatedAt {
+  amplify_core.TemporalDateTime? get updatedAt {
     return _updatedAt;
   }
 
@@ -80,7 +78,7 @@ class Blog extends Model {
 
   factory Blog({String? id, required String name, List<Post>? posts}) {
     return Blog._internal(
-        id: id == null ? UUID.getUUID() : id,
+        id: id == null ? amplify_core.UUID.getUUID() : id,
         name: name,
         posts: posts != null ? List<Post>.unmodifiable(posts) : posts);
   }
@@ -103,7 +101,7 @@ class Blog extends Model {
 
   @override
   String toString() {
-    var buffer = StringBuffer();
+    var buffer = new StringBuffer();
 
     buffer.write("Blog {");
     buffer.write("id=" + "$id" + ", ");
@@ -123,21 +121,29 @@ class Blog extends Model {
         id: id, name: name ?? this.name, posts: posts ?? this.posts);
   }
 
+  Blog copyWithModelFieldValues(
+      {ModelFieldValue<String>? name, ModelFieldValue<List<Post>?>? posts}) {
+    return Blog._internal(
+        id: id,
+        name: name == null ? this.name : name.value,
+        posts: posts == null ? this.posts : posts.value);
+  }
+
   Blog.fromJson(Map<String, dynamic> json)
       : id = json['id'],
         _name = json['name'],
         _posts = json['posts'] is List
             ? (json['posts'] as List)
                 .where((e) => e?['serializedData'] != null)
                 .map((e) => Post.fromJson(
-                    Map<String, dynamic>.from(e['serializedData'])))
+                    new Map<String, dynamic>.from(e['serializedData'])))
                 .toList()
             : null,
         _createdAt = json['createdAt'] != null
-            ? TemporalDateTime.fromString(json['createdAt'])
+            ? amplify_core.TemporalDateTime.fromString(json['createdAt'])
             : null,
         _updatedAt = json['updatedAt'] != null
-            ? TemporalDateTime.fromString(json['updatedAt'])
+            ? amplify_core.TemporalDateTime.fromString(json['updatedAt'])
             : null;
 
   Map<String, dynamic> toJson() => {
@@ -156,76 +162,84 @@ class Blog extends Model {
         'updatedAt': _updatedAt
       };
 
-  static final QueryModelIdentifier<BlogModelIdentifier> MODEL_IDENTIFIER =
-      QueryModelIdentifier<BlogModelIdentifier>();
-  static final QueryField ID = QueryField(fieldName: "id");
-  static final QueryField NAME = QueryField(fieldName: "name");
-  static final QueryField POSTS = QueryField(
+  static final amplify_core.QueryModelIdentifier<BlogModelIdentifier>
+      MODEL_IDENTIFIER =
+      amplify_core.QueryModelIdentifier<BlogModelIdentifier>();
+  static final ID = amplify_core.QueryField(fieldName: "id");
+  static final NAME = amplify_core.QueryField(fieldName: "name");
+  static final POSTS = amplify_core.QueryField(
       fieldName: "posts",
-      fieldType: ModelFieldType(ModelFieldTypeEnum.model, ofModelName: 'Post'));
-  static var schema =
-      Model.defineSchema(define: (ModelSchemaDefinition modelSchemaDefinition) {
+      fieldType: amplify_core.ModelFieldType(
+          amplify_core.ModelFieldTypeEnum.model,
+          ofModelName: 'Post'));
+  static var schema = amplify_core.Model.defineSchema(
+      define: (amplify_core.ModelSchemaDefinition modelSchemaDefinition) {
     modelSchemaDefinition.name = "Blog";
     modelSchemaDefinition.pluralName = "Blogs";
 
     modelSchemaDefinition.authRules = [
-      AuthRule(
-          authStrategy: AuthStrategy.PUBLIC,
-          provider: AuthRuleProvider.APIKEY,
-          operations: [ModelOperation.READ]),
-      AuthRule(
-          authStrategy: AuthStrategy.PUBLIC,
-          provider: AuthRuleProvider.IAM,
-          operations: [ModelOperation.READ]),
-      AuthRule(
-          authStrategy: AuthStrategy.PRIVATE,
-          provider: AuthRuleProvider.IAM,
-          operations: [ModelOperation.READ]),
-      AuthRule(
-          authStrategy: AuthStrategy.PRIVATE,
-          provider: AuthRuleProvider.USERPOOLS,
-          operations: [ModelOperation.READ]),
-      AuthRule(
-          authStrategy: AuthStrategy.OWNER,
+      amplify_core.AuthRule(
+          authStrategy: amplify_core.AuthStrategy.PUBLIC,
+          provider: amplify_core.AuthRuleProvider.APIKEY,
+          operations: const [amplify_core.ModelOperation.READ]),
+      amplify_core.AuthRule(
+          authStrategy: amplify_core.AuthStrategy.PUBLIC,
+          provider: amplify_core.AuthRuleProvider.IAM,
+          operations: const [amplify_core.ModelOperation.READ]),
+      amplify_core.AuthRule(
+          authStrategy: amplify_core.AuthStrategy.PRIVATE,
+          provider: amplify_core.AuthRuleProvider.IAM,
+          operations: const [amplify_core.ModelOperation.READ]),
+      amplify_core.AuthRule(
+          authStrategy: amplify_core.AuthStrategy.PRIVATE,
+          provider: amplify_core.AuthRuleProvider.USERPOOLS,
+          operations: const [amplify_core.ModelOperation.READ]),
+      amplify_core.AuthRule(
+          authStrategy: amplify_core.AuthStrategy.OWNER,
           ownerField: "owner",
           identityClaim: "cognito:username",
-          provider: AuthRuleProvider.USERPOOLS,
-          operations: [
-            ModelOperation.CREATE,
-            ModelOperation.READ,
-            ModelOperation.UPDATE,
-            ModelOperation.DELETE
+          provider: amplify_core.AuthRuleProvider.USERPOOLS,
+          operations: const [
+            amplify_core.ModelOperation.CREATE,
+            amplify_core.ModelOperation.READ,
+            amplify_core.ModelOperation.UPDATE,
+            amplify_core.ModelOperation.DELETE
           ])
     ];
 
-    modelSchemaDefinition.addField(ModelFieldDefinition.id());
+    modelSchemaDefinition.addField(amplify_core.ModelFieldDefinition.id());
 
-    modelSchemaDefinition.addField(ModelFieldDefinition.field(
+    modelSchemaDefinition.addField(amplify_core.ModelFieldDefinition.field(
         key: Blog.NAME,
         isRequired: true,
-        ofType: ModelFieldType(ModelFieldTypeEnum.string)));
+        ofType: amplify_core.ModelFieldType(
+            amplify_core.ModelFieldTypeEnum.string)));
 
-    modelSchemaDefinition.addField(ModelFieldDefinition.hasMany(
+    modelSchemaDefinition.addField(amplify_core.ModelFieldDefinition.hasMany(
         key: Blog.POSTS,
         isRequired: false,
         ofModelName: 'Post',
         associatedKey: Post.BLOG));
 
-    modelSchemaDefinition.addField(ModelFieldDefinition.nonQueryField(
-        fieldName: 'createdAt',
-        isRequired: false,
-        isReadOnly: true,
-        ofType: ModelFieldType(ModelFieldTypeEnum.dateTime)));
-
-    modelSchemaDefinition.addField(ModelFieldDefinition.nonQueryField(
-        fieldName: 'updatedAt',
-        isRequired: false,
-        isReadOnly: true,
-        ofType: ModelFieldType(ModelFieldTypeEnum.dateTime)));
+    modelSchemaDefinition.addField(
+        amplify_core.ModelFieldDefinition.nonQueryField(
+            fieldName: 'createdAt',
+            isRequired: false,
+            isReadOnly: true,
+            ofType: amplify_core.ModelFieldType(
+                amplify_core.ModelFieldTypeEnum.dateTime)));
+
+    modelSchemaDefinition.addField(
+        amplify_core.ModelFieldDefinition.nonQueryField(
+            fieldName: 'updatedAt',
+            isRequired: false,
+            isReadOnly: true,
+            ofType: amplify_core.ModelFieldType(
+                amplify_core.ModelFieldTypeEnum.dateTime)));
   });
 }
 
-class _BlogModelType extends ModelType<Blog> {
+class _BlogModelType extends amplify_core.ModelType<Blog> {
   const _BlogModelType();
 
   @override
@@ -239,13 +253,14 @@ class _BlogModelType extends ModelType<Blog> {
   }
 }
 
-/// This is an auto generated class representing the model identifier
-/// of [Blog] in your schema.
-@immutable
-class BlogModelIdentifier implements ModelIdentifier<Blog> {
+/**
+ * This is an auto generated class representing the model identifier
+ * of [Blog] in your schema.
+ */
+class BlogModelIdentifier implements amplify_core.ModelIdentifier<Blog> {
   final String id;
 
-  /// Create an instance of BlogModelIdentifier using [id] the primary key.
+  /** Create an instance of BlogModelIdentifier using [id] the primary key. */
   const BlogModelIdentifier({required this.id});
 
   @override