A Working Example

A full working example of using Ogurets, Flutter for Mobile, the OpenAPi generator for Dart and Java, a Java server, e2e tests for api and Flutter app and documentation.

Prerequisites:

Java 11+.

Maven (optional if running mvn commands)

Flutter SDK

Docker

authors

• Richard Vowles, Software Developer (https://www.linkedin.com/in/richard-vowles-72035193/)

• Irina Southwell (https://nz.linkedin.com/in/irina-southwell-9727a422)

Counter Example

This is an extension of the Counter example that comes with flutter. The api simply adds a reset, increase and get api.

folders

• api - holds the OpenAPI specification yaml file for the back-end Counter service.

• java-server - holds the java server code

• example_mobile_client - holds the flutter client

• dart_e2e - holds the e2e tests for the back-end service written in Dart and using Ogurets - Cucumber for Dart package

• dart_api - holds the generated code for the e2e client

Building the java server

You can build it as a Docker image:

cd java-server
mvn -Pdocker clean package
docker load -i target/jib-image.tar
docker-compose up

It will be running on port 8076, and you can check this with a curl:

curl -v http://localhost:8076/counter

Generate client API code to be used by Flutter app and back-end e2e tests

cd dart_api

run the following command to generate client code with Open API Dart codegen plugin

java -cp openapi-generator-cli-4.2.1.jar:openapi-dart-generator-2.2.jar org.openapitools.codegen.OpenAPIGenerator generate -i ../api/src/main/resources/counter.yaml — additional-properties pubName=counterapi -g dart2-api — enable-post-process-file

alternatively if you have maven installed you can run

mvn clean generate-sources

to install dart dependencies run

pub get

Building and running Flutter app

cd example_mobile_client
pub get
flutter run

Running back-end e2e tests with Ogurets - Cucumber for Dart

cd dart_e2e
pub get
dart --enable-asserts tests/ogurets_run.dart

Running Flutter mobile e2e tests with Ogurets - Cucumber for Dart

Launch iOS or Android emulator

cd example_mobile_client
pub get
dart --enable-asserts test_driver/ogurets_flutter_test.dart

note, one scenario should fail for demo purposes of an error case

read more on Ogurets-Cucumber for Dart here https://github.com/dart-ogurets/Ogurets

There are a few deliberate design decisions here, it is only an example and certainly not one we would run in a production scenario. It is missing:

• an api lifecycle to shutdown the server

• healthcheck endpoints

• proper jersey configuration for exception handling, bean validation, logging and tracing

• proper logging infrastructure that is k8s aware