marvelous

the marvelous framework - microservices for node.js

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();

API Reference

Gateway

Properties

Name	Example
environment string the gateway environment	"production"
enableLogging string enables gateway logging	true
knownErrors GatewayError[] an array of gateway errors	[ AuthServiceError ]
onLoad Function fires when gateway is loaded
onStart Function fires when gateway is started
onStop Function fires when gateway is stopped
routes GatewayRoute[] an array of gateway routes	[ UsersRoute ]
url string the gateway url	"http://localhost:3000"

GatewayError

Properties

Name	Example
code number the error status code	401
name string the error name	"AuthGatewayError"
message Function the error message	"You must be logged in."

GatewayMethod

Properties

Name	Example
handler Function the gateway method handler
schema object the gateway method schema

GatewayRoute

Properties

Name	Example
uri string the gateway route uri	"/users"
delete GatewayMethod DELETE method	DeleteUserMethod
get GatewayMethod GET method	GetUsersMethod
options GatewayMethod OPTIONS method	OptionsUsersMethod
patch GatewayMethod PATCH method	PatchUserMethod
post GatewayMethod POST method	PostUsersMethod
put GatewayMethod PUT method	PutUserMethod

Service

Properties

Name	Example
calls object the service calls	{ createUser: CreateUserCall }
environment string the service environment	"production"
enableLogging string enables service logging	true
onLoad Function fires when service is loaded
onStart Function fires when service is started
onStop Function fires when service is stopped
url string the service url	"http://localhost:3000"

ServiceCall

Properties

Name	Example
handler Function the service call handler
schema object the service call schema

ServiceError

Properties

Name	Example
name string the error name	"AuthGatewayError"
message Function the error message	"You must be logged in."