miguelfdezc / fullstack-assignment

Fullstack position skill assessment home assignment.

Planet fullstack-assignment

Full-Stack position skill assessment home assignment.

Context

As a Full-Stack developer in Planet Dataset, you will be asked to participate in the design and implementation of new features that will be used in our price-management platform for eCommerce.

New features usually involves three different tasks:

1. Implementing an interface to configure the user's preferences.
2. Implementing API endpoints to retrieve data such as result examples.
3. Implementing asynchronous tasks that apply the changes to our clients' stores.

This is the workflow that we tried to replicate in this task.

Overview

We provide you with a project that has a database, an API, a service that executes periodically and a web app.

This project has part of the functionality of fictitious software solution that provides stock exchange data services: it allows the user of the web app to subscribe to currencies, and see the current exchange prices of those he/she whishes to follow.

You are responsible of finishing the app by implementing:

• The code that executes periodically and fetches the forex data.
• The code for the API endpoint that sends that data to the front-end.
• The front-end code to see and edit the list of currencies currently followed, along with their stock prices.

About this repository

This repository holds the basic project structure for implementing a NodeJS based API and service, and an Angular web app.

The code is organized as follows:

• services
  • \ api - A NodeJS project with ExpressJS, TypeScript and Mongoose to implement the API.
  • \ front-end - An Angular project with TypeScript, SCSS, Material and NgRX to implement the web app. Implementation details can be found in services/front-end/README.md.
  • \ service - A NodeJS-based service with TypeScript and Mongoose that is setup to run periodically in order to implement asynchronous tasks.
• docker-compose.slim.yml -
• docker-compose.yml -
• dump -
• Makefile - Makefile for your ease of development, see below
• frontend.mk - Makefile rules for the web app.
• backend.mk - Makefile rules for the API.
• service.mk - Makefile rules for the asynchronous task.
• README.md - This file.
• LICENSE

Disclaimer: The purpose and usage of this repo is solely for insight acquisition regarding problem-solving, and does not represent an existing and ongoing implementation task.

PS: We provide this structure as a starting point but you may discard it and approach the task in any other way.

The problem

The solution you are required to design and implement is geared towards collecting historic exchange prices from the currencies the API user wants to EUR. With this in mind we need a system that provides an API for adding, removing and listing the currencies that are being followed at the moment, and an additional endpoint for retrieving such historic data.

We already provide the endpoints for managing subscriptions so you can focus on the use case of fetching, saving and showing historical data.

The workflow that the system should support is:

1. The API user adds or removes currencies from the followed ones, by the currency code.
2. The API user is able to see the followed currencies using the corresponding endpoint
3. The system, periodically, fetches the stock exchange price from each followed currency to Euros (EUR).
4. The user can see the historical data for the followed currencies, which includes basic data such as ask, bid, and spread; and additional calculated stats.

We recommend using the alphavantage API for retrieving the data as it is free and the endpoint for retrieving the data is well documented and easy to use. See the docs: https://www.alphavantage.co/documentation/#fx-daily

Tasks

1. Forex data retrieval

What we want

Implement recurrent data retrieval for each of the followed currencies. This data can be obtained from external APIs such as the one we propose: Alphavantage.

The data needs to be persisted on database in order to have a register of how currencies's values change along time, so that it can later be fetched from the front-end.

We already provide you with a service that runs periodically and where you could implement any asynchronous code for this task. The code can be found at services/service.

What we will evaluate

• The way the candidates organizes code and looks for a neat and optimized environment.
• How the candidate models the domain in order to handle more types of data sources.

2. API endpoint for retrieving the fetched forex data

What we want

We hope the candidate to implement an API endpoint to retrieve the historical data for currently followed currencies (/api/currency/:code/history or /api/forex/history could be valid options)

We already provide you with a working API at services/api where you could add your endpoint.

What we will evaluate

• How the candidate adapts to the provided architecture and environment
• The use good plractices as design patterns, SOLID principles, domain-driven development, testing... would give you points against other candidates!
• At this point a clean and readable code is essencial to work in a team where every code is shared, so we'll also take a look for this!

PD: Feel completely free to add/update any feature given as long as it makes sense in the proposed domain.

3. Interface to list followed currencies

What we want

We provide you with three basic endpoints for subscribing, unsubscribing and listing the subscriptions to different currencies:

• [POST] /api/currency Subscribe new currency
• [PUT] /api/currency/:code Unsubscribe currency
• [GET] /api/currencies Get subscribed currencies

We want a view that lists the subscribed currencies along with their forex data, and that allows to add or remove subscriptions. Here is a mockup of it could look, although you are free to design it however you feel it works best.

What we will evaluate

• Whether the interface fulfills the functional requirements: it shows the current currency subscriptions along with their data, and it allows adding or removing subscriptions.
• How functionality is organized though components and services.
• Efective use of Angular life cycle hooks to perform data subscription and tearing.
• A coherent implementation of the interface that involves a limited number of spaces, fonts and colors; and the use of CSS3 and SCSS features to keep styles easily maintainable.

How to run the services

We provide you with Makefile rules for you to lift individual services:

• The services/api directory holds the code for the API. The following make commands are available:

  • backend-build Builds the corresponding Docker images.
  • backend-up Raises the platform.
  • backend-up-slim Raises the platform without the service service running in the background (just the db and API).
  • backend-down Shuts down the platform. Requires having the platform up (you can use make backend-up)
  • backend-dump Dumps the database contents to a dump folder. Requires having the platform up (you can use make backend-up)
  • backend-load Loads the database contents from a dump folder. Requires having the platform up (you can use make backend-up)
  • backend-dbshell Connects to the database shell. Requires having the platform up (you can use make backend-up)
  • backend-test Runs the API tests with database dump and restore. Requires having the platform up (you can use make backend-up)

• The services/services directory holds the code for the API. The following make commands are available:

  • service-build Builds the corresponding Docker images.
  • service-run Executes just once the service.. Requires having the platform up (you can use make service-up)
  • service-dev Executes the service each time the code changes. Requires having the platform up (you can use make service-up)

• The services/front-end directory holds the code for the Front-end. The following make commands are available:

  • frontend-build Builds the corresponding app dist files.
  • frontend-dev Runs the front-end service locally (accessible at http://localhost:4200). It will install the dependencies (requires having a local installation of node).

We designed the repo to work in such a way that the API and the web app could run independently from a cron job that executes the service, and where you could place recurrent asynchronous code. Therefore, there are two use cases that we think you could face:

• Having the API up (with hot-reloading), along with the generic service (without hot-reloading) running periodically using cron. This would be the complete platform running:

  make backend-up
  make frontend-dev

• Having the API up (with hot-reloading) without the generic service. This way you could develop the API and web app and, whenever you want to execute the service, you still have the option to do it once or have it execute each time the code has changed:

  make backend-up-slim
  make frontend-dev
  # execute the generic service once
  make service-run
  # execute the generic service each time the code changes (hot-reloading)
  make service-dev

fullstack-assignment

Full-Stack position skill assessment home assignment.

• Fixed subscribe/unsubscribe creation of infinite currencies (changed into update hasSubscription)
• Implemented the i18n translations for the front-end
• Used Material Angular