feat: Looker SDK generator for the Dart language

dart/looker_sdk/.gitignore

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+# the dart lib needs to be included in source control
+!lib/**
+
+# the following are excluded from source control.
+.env*
+temp/
+.dart_tool/
+.packages
+build/
+# recommendation is NOT to commit for library packages.
+pubspec.lock
+

dart/looker_sdk/README.md

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+# Looker API for Dart SDK
+
+A dart implementation of the Looker API. Note that only the SDK for Looker 4.0 API is generated.
+
+## Usage
+
+See examples and tests.
+
+Create a `.env` file in the same directory as this `README.md`. The format is as follows:
+
+```
+URL=looker_instance_api_endpoint
+CLIENT_ID=client_id_from_looker_instance
+CLIENT_SECRET=client_secret_from_looker_instance
+```
+
+## Add to project
+
+Add the following to project `pubspec.yaml` dependencies. Replace `{SHA}` with the sha of the version of the SDK you want to use (a more permanent solution may be added in the future).
+
+```
+  looker_sdk:
+    git:
+      url: https://github.com/looker-open-source/sdk-codegen
+      ref: {SHA}
+      path: dart/looker_sdk
+```
+
+## Developing
+
+Relies on `yarn` and `dart` being installed. This was developed with `dart` version `2.15.1` so the recommendation is to have a version of dart that is at least at that version.
+
+### Generate
+
+Run `yarn sdk Gen` from the `{reporoot}`. Note that the SDK generator needs to be built using `yarn build`. If changing the generator run 'yarn watch` in a separate window. This command generates two files:
+
+1. `{reporoot}/dart/looker_sdk/lib/src/sdk/methods.dart`
+2. `{reporoot}/dart/looker_sdk/lib/src/sdk/models.dart`
+
+The files are automatically formatted using `dart` tooling. Ensure that the `dart` binary is available on your path.
+
+### Run example
+
+Run `yarn example` from `{reporoot}/dart/looker_sdk`
+
+### Run tests
+
+Run `yarn test:e2e` from `{reporoot}/dart/looker_sdk` to run end to end tests. Note that these tests require that a `.env` file has been created (see above) and that the Looker instance is running.
+
+Run `yarn test:unit` from `{reporoot}/dart/looker_sdk` to run unit tests. These tests do not require a Looker instance to be running.
+
+Run `yarn test` from `{reporoot}/dart/looker_sdk` to run all tests.
+
+### Run format
+
+Run `yarn format` from `{reporoot}/dart/looker_sdk` to format the `dart` files correctly. This should be run if you change any of the run time library `dart` files. The repo CI will run the `format-check` and will fail if the files have not been correctly formatted.
+
+### Run format-check
+
+Run `yarn format-check` from `{reporoot}/dart/looker_sdk` to verify the formatting of the `dart` files. This is primarily for CI. It's the same as `yarn format` but does not format the files.
+
+### Run analyze
+
+Run `yarn format-analyze` from `{reporoot}/dart/looker_sdk` to lint the `dart` files. This should be run prior to commiting as CI will this task and will fail if the script fails.
+
+## TODOs
+
+1. Make enum mappers private to package. They are currently public as some enums are not used by by the models and a warning for unused class is displayed by visual code. It could also be a bug in either the generator or the spec generator (why are enums being generated if they are not being used?).
+2. Add optional timeout parameter to methods and implement timeout support.
+3. Add additional authorization methods to api keys.
+4. Revisit auth session. There is some duplication of code in generated methods.
+5. Add base class for models. Move common props to base class. Maybe add some utility methods for primitive types. Should reduce size of models.dart file.
+6. More and better generator tests. They are a bit hacky at that moment.
+7. Generate dart documentation.
+
+## Notes
+
+1. Region folding: Dart does not currently support region folding. Visual Studio Code has a generic extension that supports region folding for dart. [Install](https://marketplace.visualstudio.com/items?itemName=maptz.regionfolder) if you wish the generated regions to be honored.

dart/looker_sdk/analysis_options.yaml

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+include: package:lints/recommended.yaml
+
+analyzer:

dart/looker_sdk/example/main.dart

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+import 'dart:io';
+import 'dart:typed_data';
+import 'package:looker_sdk/index.dart';
+import 'package:dotenv/dotenv.dart' show load, env;
+
+void main() async {
+  load();
+  var sdk = await createSdk();
+  await runLooks(sdk);
+  await runDashboardApis(sdk);
+  await runConnectionApis(sdk);
+}
+
+Future<LookerSDK> createSdk() async {
+  return await Sdk.createSdk({
+    'base_url': env['URL'],
+    'verify_ssl': false,
+    'credentials_callback': credentialsCallback
+  });
+}
+
+Future<void> runLooks(LookerSDK sdk) async {
+  try {
+    var looks = await sdk.ok(sdk.allLooks());
+    if (looks.isNotEmpty) {
+      for (var look in looks) {
+        print(look.title);
+      }
+      var look = await sdk.ok(sdk.runLook(looks[looks.length - 1].id, 'png'));
+      var dir = Directory('./temp');
+      if (!dir.existsSync()) {
+        dir.createSync();
+      }
+      File('./temp/look.png').writeAsBytesSync(look as Uint8List);
+      look = await sdk.ok(sdk.runLook(looks[looks.length - 1].id, 'csv'));
+      File('./temp/look.csv').writeAsStringSync(look as String);
+    }
+  } catch (error, stacktrace) {
+    print(error);
+    print(stacktrace);
+  }
+}
+
+Future<void> runDashboardApis(LookerSDK sdk) async {
+  try {
+    var dashboards = await sdk.ok(sdk.allDashboards());
+    for (var dashboard in dashboards) {
+      print(dashboard.title);
+    }
+    var dashboard = await sdk.ok(sdk.dashboard(dashboards[0].id));
+    print(dashboard.toJson());
+  } catch (error, stacktrace) {
+    print(error);
+    print(stacktrace);
+  }
+}
+
+Future<void> runConnectionApis(LookerSDK sdk) async {
+  try {
+    var connections = await sdk.ok(sdk.allConnections());
+    for (var connection in connections) {
+      print(connection.name);
+    }
+    var connection = await sdk
+        .ok(sdk.connection(connections[0].name, fields: 'name,host,port'));
+    print(
+        'name=${connection.name} host=${connection.host} port=${connection.port}');
+    var newConnection = WriteDBConnection();
+    SDKResponse resp = await sdk.connection('TestConnection');
+    if (resp.statusCode == 200) {
+      print('TestConnection already exists');
+    } else {
+      newConnection.name = 'TestConnection';
+      newConnection.dialectName = 'mysql';
+      newConnection.host = 'db1.looker.com';
+      newConnection.port = '3306';
+      newConnection.username = 'looker_demoX';
+      newConnection.password = 'look_your_data';
+      newConnection.database = 'demo_db2';
+      newConnection.tmpDbName = 'looker_demo_scratch';
+      connection = await sdk.ok(sdk.createConnection(newConnection));
+      print('created ${connection.name}');
+    }
+    var updateConnection = WriteDBConnection();
+    updateConnection.username = 'looker_demo';
+    connection =
+        await sdk.ok(sdk.updateConnection('TestConnection', updateConnection));
+    print('Connection updated: username=${connection.username}');
+    var testResults = await sdk.ok(
+        sdk.testConnection('TestConnection', tests: DelimList(['connect'])));
+    if (testResults.isEmpty) {
+      print('No connection tests run');
+    } else {
+      for (var i in testResults) {
+        print('test result: ${i.name}=${i.message}');
+      }
+    }
+    var deleteResult = await sdk.ok(sdk.deleteConnection('TestConnection'));
+    print('Delete result $deleteResult');
+  } catch (error, stacktrace) {
+    print(error);
+    print(stacktrace);
+  }
+}
+
+Map credentialsCallback() {
+  return {'client_id': env['CLIENT_ID'], 'client_secret': env['CLIENT_SECRET']};
+}

dart/looker_sdk/lib/index.dart

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+export 'src/looker_sdk.dart';

dart/looker_sdk/lib/src/looker_sdk.dart

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+export 'rtl/api_types.dart';
+export 'rtl/api_methods.dart';
+export 'rtl/api_settings.dart';
+export 'rtl/auth_session.dart';
+export 'rtl/auth_token.dart';
+export 'rtl/constants.dart';
+export 'rtl/sdk.dart';
+export 'rtl/transport.dart';
+export 'sdk/methods.dart';
+export 'sdk/models.dart';

dart/looker_sdk/lib/src/rtl/api_methods.dart

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+import 'dart:convert';
+import 'auth_session.dart';
+import 'transport.dart';
+
+class APIMethods {
+  final AuthSession _authSession;
+
+  APIMethods(this._authSession);
+
+  Future<T> ok<T>(Future<SDKResponse<T>> future) async {
+    var response = await future;
+    if (response.ok) {
+      return response.result;
+    } else {
+      throw Exception(
+          'Invalid SDK response ${response.statusCode}/${response.statusText}/${response.decodedRawResult}');
+    }
+  }
+
+  Future<SDKResponse<T>> get<T>(
+      T Function(dynamic responseData, String contentType) responseHandler,
+      String path,
+      [dynamic queryParams,
+      dynamic body]) async {
+    var headers = await _getHeaders();
+    return _authSession.transport.request(
+      responseHandler,
+      HttpMethod.get,
+      '${_authSession.apiPath}$path',
+      queryParams,
+      body,
+      headers,
+    );
+  }
+
+  Future<SDKResponse> head(String path,
+      [dynamic queryParams, dynamic body]) async {
+    var headers = await _getHeaders();
+    dynamic responseHandler(dynamic responseData, String contentType) {
+      return null;
+    }
+
+    return _authSession.transport.request(responseHandler, HttpMethod.head,
+        '${_authSession.apiPath}$path', queryParams, body, headers);
+  }
+
+  Future<SDKResponse<T>> delete<T>(
+      T Function(dynamic responseData, String contentType) responseHandler,
+      String path,
+      [dynamic queryParams,
+      dynamic body]) async {
+    var headers = await _getHeaders();
+    return _authSession.transport.request(responseHandler, HttpMethod.delete,
+        '${_authSession.apiPath}$path', queryParams, body, headers);
+  }
+
+  Future<SDKResponse<T>> post<T>(
+      T Function(dynamic responseData, String contentType) responseHandler,
+      String path,
+      [dynamic queryParams,
+      dynamic body]) async {
+    var headers = await _getHeaders();
+    var requestBody = body == null ? null : jsonEncode(body);
+    return _authSession.transport.request(responseHandler, HttpMethod.post,
+        '${_authSession.apiPath}$path', queryParams, requestBody, headers);
+  }
+
+  Future<SDKResponse<T>> put<T>(
+      T Function(dynamic responseData, String contentType) responseHandler,
+      String path,
+      [dynamic queryParams,
+      dynamic body]) async {
+    var headers = await _getHeaders();
+    return _authSession.transport.request(responseHandler, HttpMethod.put,
+        '${_authSession.apiPath}$path', queryParams, body, headers);
+  }
+
+  Future<SDKResponse<T>> patch<T>(
+      T Function(dynamic responseData, String contentType) responseHandler,
+      String path,
+      [dynamic queryParams,
+      dynamic body]) async {
+    var headers = await _getHeaders();
+    Object requestBody;
+    if (body != null) {
+      body.removeWhere((key, value) => value == null);
+      requestBody = jsonEncode(body);
+    }
+    return _authSession.transport.request(responseHandler, HttpMethod.patch,
+        '${_authSession.apiPath}$path', queryParams, requestBody, headers);
+  }
+
+  Future<Map<String, String>> _getHeaders() async {
+    var headers = <String, String>{
+      'x-looker-appid': _authSession.transport.settings.agentTag
+    };
+    headers.addAll(_authSession.authenticate());
+    return headers;
+  }
+}

dart/looker_sdk/lib/src/rtl/api_settings.dart

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+import 'constants.dart';
+
+class ApiSettings {
+  String _baseUrl;
+  bool _verifySsl;
+  int _timeout;
+  String _agentTag;
+  Function _credentialsCallback;
+
+  ApiSettings.fromMap(Map settings) {
+    _baseUrl = settings.containsKey('base_url') ? settings['base_url'] : '';
+    _verifySsl =
+        settings.containsKey('verify_ssl') ? settings['verify_ssl'] : true;
+    _timeout =
+        settings.containsKey('timeout') ? settings['timeout'] : defaultTimeout;
+    _agentTag = settings.containsKey('agent_tag')
+        ? settings['agent_tag']
+        : '$agentPrefix $lookerVersion';
+    _credentialsCallback = settings.containsKey(('credentials_callback'))
+        ? settings['credentials_callback']
+        : null;
+  }
+
+  bool isConfigured() {
+    return _baseUrl != null;
+  }
+
+  void readConfig(String section) {
+    throw UnimplementedError('readConfig');
+  }
+
+  String get version {
+    return apiVersion;
+  }
+
+  String get baseUrl {
+    return _baseUrl;
+  }
+
+  bool get verifySsl {
+    return _verifySsl;
+  }
+
+  int get timeout {
+    return _timeout;
+  }
+
+  String get agentTag {
+    return _agentTag;
+  }
+
+  Function get credentialsCallback {
+    return _credentialsCallback;
+  }
+}

dart/looker_sdk/lib/src/rtl/api_types.dart

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+class DelimList<T> {
+  final List<T> _items;
+  final String _separator;
+  final String _prefix;
+  final String _suffix;
+
+  DelimList(List<T> items,
+      [String separator = ',', String prefix = '', String suffix = ''])
+      : _items = items,
+        _separator = separator,
+        _prefix = prefix,
+        _suffix = suffix;
+
+  @override
+  String toString() {
+    return '$_prefix${_items.join((_separator))}$_suffix';
+  }
+}