Add an option to configure generator's output_dir

generator/integration-tests/config/.gitignore

@@ -0,0 +1,4 @@
+# start with an empty project, without a objectbox-model.json
+objectbox-model.json
+objectbox.*
+testdata

generator/integration-tests/config/1.dart

@@ -0,0 +1,48 @@
+import 'dart:io';
+import 'dart:typed_data';
+
+import 'package:test/test.dart';
+
+import 'lib/lib.dart';
+import 'lib/custom/objectbox.g.dart';
+import '../test_env.dart';
+import '../common.dart';
+
+void main() {
+  late TestEnv<A> env;
+  final jsonModel = readModelJson('lib/custom');
+  final defs = getObjectBoxModel();
+  final model = defs.model;
+
+  setUp(() {
+    env = TestEnv<A>(defs);
+  });
+
+  tearDown(() {
+    env.close();
+  });
+
+  commonModelTests(defs, jsonModel);
+
+  test('project must be generated properly', () {
+    expect(TestEnv.dir.existsSync(), true);
+    expect(File('lib/custom/objectbox.g.dart').existsSync(), true);
+    expect(File('lib/custom/objectbox-model.json').existsSync(), true);
+  });
+
+  // Very simple tests to ensure imports and generated code is correct.
+
+  test('types', () {
+    expect(property(model, 'A.text').type, OBXPropertyType.String);
+  });
+
+  test('db-ops-A', () {
+    final box = env.store.box<A>();
+    expect(box.count(), 0);
+
+    final inserted = A();
+    box.put(inserted);
+    expect(inserted.id, 1);
+    box.get(inserted.id!)!;
+  });
+}

generator/integration-tests/config/lib/custom/.keep

@@ -0,0 +1 @@
+This file just exists so its folder is created by git.

generator/integration-tests/config/lib/lib.dart

@@ -0,0 +1,13 @@
+import 'dart:typed_data';
+
+import 'package:objectbox/objectbox.dart';
+
+import 'custom/objectbox.g.dart';
+
+@Entity()
+class A {
+  int? id;
+  String? text;
+
+  A();
+}

generator/integration-tests/config/pubspec.yaml

@@ -0,0 +1,29 @@
+name: objectbox_generator_test
+
+environment:
+  sdk: ">=2.12.0 <3.0.0"
+
+dependencies:
+  objectbox: any
+
+dev_dependencies:
+  objectbox_generator: any
+  test: any
+  build_runner: any
+  build_test: any
+  io: any
+  path: any
+
+dependency_overrides:
+  objectbox:
+    path: ../../../objectbox
+  objectbox_generator:
+    path: ../../
+
+
+objectbox:
+  output_dir: custom
+  # output_dir:
+  #   lib: custom
+  #   test: other
+

generator/lib/objectbox_generator.dart

@@ -1,10 +1,15 @@
 /// This package provides code generation for ObjectBox in Dart/Flutter.
+
 import 'package:build/build.dart';
-import 'src/entity_resolver.dart';
+
 import 'src/code_builder.dart';
+import 'src/config.dart';
+import 'src/entity_resolver.dart';
+
+final _config = Config.readFromPubspec();
 
 /// Finds all classes annotated with @Entity annotation and creates intermediate files for the generator.
 Builder entityResolverFactory(BuilderOptions options) => EntityResolver();
 
 /// Writes objectbox_model.dart and objectbox-model.json from the prepared .objectbox.info files found in the repo.
-Builder codeGeneratorFactory(BuilderOptions options) => CodeBuilder();
+Builder codeGeneratorFactory(BuilderOptions options) => CodeBuilder(_config);

generator/lib/src/code_builder.dart

@@ -10,29 +10,42 @@ import 'package:dart_style/dart_style.dart';
 import 'package:source_gen/source_gen.dart';
 import 'package:pubspec_parse/pubspec_parse.dart';
 
+import 'config.dart';
 import 'entity_resolver.dart';
 import 'code_chunks.dart';
 
 /// CodeBuilder collects all '.objectbox.info' files created by EntityResolver and generates objectbox-model.json and
 /// objectbox_model.dart
 class CodeBuilder extends Builder {
-  static final jsonFile = 'objectbox-model.json';
-  static final codeFile = 'objectbox.g.dart';
+  final Config _config;
 
-  @override
-  final buildExtensions = {r'$lib$': _outputs, r'$test$': _outputs};
-
-  // we can't write `jsonFile` as part of the output because we want it persisted, not removed before each generation
-  static final _outputs = [codeFile];
+  CodeBuilder(this._config);
 
-  String dir(BuildStep buildStep) => path.dirname(buildStep.inputId.path);
+  @override
+  late final buildExtensions = {
+    r'$lib$': [path.join(_config.outDirLib, _config.codeFile)],
+    r'$test$': [path.join(_config.outDirTest, _config.codeFile)]
+  };
+
+  String _dir(BuildStep buildStep) => path.dirname(buildStep.inputId.path);
+
+  String _outDir(BuildStep buildStep) {
+    var dir = _dir(buildStep);
+    if (dir.endsWith('test')) {
+      return dir + '/' + _config.outDirTest;
+    } else if (dir.endsWith('lib')) {
+      return dir + '/' + _config.outDirLib;
+    } else {
+      throw Exception('Unrecognized path being generated: $dir');
+    }
+  }
 
   @override
   FutureOr<void> build(BuildStep buildStep) async {
     // build() will be called only twice, once for the `lib` directory and once for the `test` directory
     // map from file name to a 'json' representation of entities
     final files = <String, List<dynamic>>{};
-    final glob = Glob(dir(buildStep) + '/**' + EntityResolver.suffix);
+    final glob = Glob(_dir(buildStep) + '/**' + EntityResolver.suffix);
     await for (final input in buildStep.findAssets(glob)) {
       files[input.path] = json.decode(await buildStep.readAsString(input))!;
     }
@@ -55,7 +68,7 @@ class CodeBuilder extends Builder {
 
     Pubspec? pubspec;
     try {
-      final pubspecFile = File(path.join(dir(buildStep), '../pubspec.yaml'));
+      final pubspecFile = File(path.join(_dir(buildStep), '../pubspec.yaml'));
       pubspec = Pubspec.parse(pubspecFile.readAsStringSync());
     } catch (e) {
       log.info("Couldn't load pubspec.yaml: $e");
@@ -69,8 +82,8 @@ class CodeBuilder extends Builder {
       List<ModelEntity> entities, BuildStep buildStep) async {
     // load an existing model or initialize a new one
     ModelInfo model;
-    final jsonId =
-        AssetId(buildStep.inputId.package, dir(buildStep) + '/' + jsonFile);
+    final jsonId = AssetId(
+        buildStep.inputId.package, _outDir(buildStep) + '/' + _config.jsonFile);
     if (await buildStep.canRead(jsonId)) {
       log.info('Using model: ${jsonId.path}');
       model =
@@ -95,11 +108,42 @@ class CodeBuilder extends Builder {
 
   void updateCode(ModelInfo model, List<String> infoFiles, BuildStep buildStep,
       Pubspec? pubspec) async {
+    // If output directory is not package root directory,
+    // need to prefix imports with as many '../' to be relative from root.
+    final rootPath = _dir(buildStep);
+    final outPath = _outDir(buildStep);
+    final rootDir = Directory(rootPath).absolute;
+    var outDir = Directory(outPath).absolute;
+    var prefix = '';
+
+    if (!outDir.path.startsWith(rootDir.path)) {
+      throw InvalidGenerationSourceError(
+          'configured output_dir ${outDir.path} is not a '
+          'subdirectory of the source directory ${rootDir.path}');
+    }
+
+    while (outDir.path != rootDir.path) {
+      final parent = outDir.parent;
+      if (parent.path == outDir.path) {
+        log.warning(
+            'Failed to find package root from output directory, generated imports might be incorrect.');
+        prefix = '';
+        break; // Reached top-most directory, stop searching.
+      }
+      outDir = parent;
+      prefix += '../';
+    }
+    if (prefix.isNotEmpty) {
+      log.info(
+          'Output directory not in package root, adding prefix to imports: ' +
+              prefix);
+    }
+
     // transform '/lib/path/entity.objectbox.info' to 'path/entity.dart'
     final imports = infoFiles
         .map((file) => file
             .replaceFirst(EntityResolver.suffix, '.dart')
-            .replaceFirst(dir(buildStep) + '/', ''))
+            .replaceFirst(rootPath + '/', prefix))
         .toList();
 
     var code = CodeChunks.objectboxDart(model, imports, pubspec);
@@ -109,7 +153,7 @@ class CodeBuilder extends Builder {
     } finally {
       // Write the code even after a formatter error so it's easier to debug.
       final codeId =
-          AssetId(buildStep.inputId.package, dir(buildStep) + '/' + codeFile);
+          AssetId(buildStep.inputId.package, outPath + '/' + _config.codeFile);
       log.info('Generating code: ${codeId.path}');
       await buildStep.writeAsString(codeId, code);
     }

generator/lib/src/config.dart

@@ -0,0 +1,56 @@
+import 'dart:io';
+
+import 'package:yaml/yaml.dart';
+
+const _pubspecFile = 'pubspec.yaml';
+const _pubspecKey = 'objectbox';
+
+/// Config reads and holds configuration for the code generator.
+///
+/// Expected format in pubspec.yaml:
+/// ```
+/// objectbox:
+///   output_dir: custom
+///   # Or optionally specify lib and test folder separately.
+///   # output_dir:
+///   #   lib: custom
+///   #   test: other
+/// ```
+class Config {
+  final String jsonFile;
+  final String codeFile;
+  final String outDirLib;
+  final String outDirTest;
+
+  Config._(
+      {String? jsonFile,
+      String? codeFile,
+      String? outDirLib,
+      String? outDirTest})
+      : jsonFile = jsonFile ?? 'objectbox-model.json',
+        codeFile = codeFile ?? 'objectbox.g.dart',
+        outDirLib = outDirLib ?? '',
+        outDirTest = outDirTest ?? '';
+
+  factory Config.readFromPubspec() {
+    final file = File(_pubspecFile);
+    if (file.existsSync()) {
+      final yaml = loadYaml(file.readAsStringSync())[_pubspecKey] as YamlMap?;
+      if (yaml != null) {
+        late final String? outDirLib;
+        late final String? outDirTest;
+        final outDirYaml = yaml['output_dir'];
+
+        if (outDirYaml is YamlMap) {
+          outDirLib = outDirYaml['lib'];
+          outDirTest = outDirYaml['test'];
+        } else {
+          outDirLib = outDirTest = outDirYaml as String?;
+        }
+
+        return Config._(outDirLib: outDirLib, outDirTest: outDirTest);
+      }
+    }
+    return Config._();
+  }
+}

generator/pubspec.yaml

@@ -17,6 +17,7 @@ dependencies:
   path: ^1.8.0
   source_gen: ^1.0.0
   pubspec_parse: ^1.0.0
+  yaml: ^3.0.0
 
 # NOTE: remove before publishing
 dependency_overrides:

objectbox/CHANGELOG.md

@@ -1,5 +1,7 @@
 ## latest
 
+* Add an option to change code-generator's `output_dir` in `pubspec.yaml`. #341
+
 ## 1.3.0 (2021-11-22)
 
 * Support annotating a single property with `@Unique(onConflict: ConflictStrategy.replace)` to 

objectbox/example/README.md

@@ -52,6 +52,18 @@ list (e.g. .gitignore), otherwise the build_runner will complain about it being
 > annotations there. This is useful if you need a separate test DB. If you're just writing tests for your own code, you
 > won't have any annotations in the `test` folder so no DB will be created there.
 
+To customize the directory (relative to the package root) where the generated files are written,
+add the following to your `pubspec.yaml`:
+```
+objectbox:
+  # Writes objectbox-model.json and objectbox.g.dart to lib/custom (and test/custom).
+  output_dir: custom
+  # Or optionally specify the lib and test output folder separately.
+  # output_dir:
+  #   lib: custom
+  #   test: other
+```
+
 Creating a store
 ----------------