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marvelous

the marvelous framework - microservices for node.js

microservices

Sample Application

Task Service

This RPC service reads/writes tasks for a to-do list:

Tip: this service is accessible via http://localhost:4000

class TaskService extends Service {
  calls = {
    createTask: CreateTaskCall,
    listTasks: ListTasksCall
  };
}

class CreateTaskCall extends ServiceCall {
  handler: ICreateTaskHandler = async request => {
    const task = {
      ...request,
      id: nextTaskId
    };
    tasks.push(task);
    nextTaskId++;
    return {
      id: task.id
    };
  };
}

class ListTasksCall extends ServiceCall {
  handler: IListTasksHandler = async () => {
    return {
      tasks: tasks.map((task: IListTasksResponseTask) => ({
        id: task.id,
        text: task.text
      }))
    };
  };
}

const taskService = new TaskService({
  url: 'http://localhost:4000'
});
taskService.start();

Public Gateway

This REST gateway exposes the Task Service functionality:

Tip: this service is accessible via http://localhost:3000

class PublicGateway extends Gateway {
  routes = [TasksRoute];
}

class TasksRoute extends GatewayRoute {
  uri = '/tasks';
  methods = {
    get: GetTasksMethod,
    post: PostTasksMethod
  };
}

class GetTasksMethod extends GatewayMethod {
  handler: any = async () => {
    const result = await taskServiceClient.listTasks();
    return {
      status: 200,
      body: result.tasks
    };
  };
}

class PostTasksMethod extends GatewayMethod {
  handler: any = async (req: Request) => {
    const result = await taskServiceClient.createTask({
      text: req.body.text
    });
    return {
      status: 201,
      body: {
        id: result.id
      }
    };
  };
}

const publicGateway = new PublicGateway({
  url: 'http://localhost:3000'
});
publicGateway.start();