REQUIREMENTS.md

HelloFresh Senior Backend Developer Test

Hello and thanks for taking the time to try this out.

The goal of this test is to assert (to some degree) your coding and architectural skills. You're given a simple problem so you can focus on showcasing development techniques. We encourage you to overengineer the solution a little to show off what you can do - assume you're building a production-ready application that other developers will need to work on and add to over time.

We accept tests written in PHP, Go, or Python - your choice of language should be one you can demonstrate being comfortable coding in, to maximise your chance of a positive code review.

You're allowed and encouraged to use third party libraries, as long as you put them together yourself without relying on a framework or microframework to do it for you. An effective developer knows what to build and what to reuse, but also how his/her tools work. Be prepared to answer some questions about those libraries, like why you chose them and what other alternatives you're familiar with.

As this is a code review process, please avoid adding generated code to the project. This makes our jobs as reviewers more difficult, as we can't review code you didn't write. This means avoiding libraries like Propel ORM, which generates thousands of lines of code in stub files.

Note: While we love open source here at HelloFresh, please do not create a public repo with your test in! This challenge is only shared with people interviewing, and for obvious reasons we'd like it to remain this way.

Prerequsites

We use Docker to administer this test. This ensures that we get an identical result to you when we test your application out, and it also matches our internal development workflows. If you don't have it already, you'll need Docker installed on your machine. The application MUST run in the Docker containers - if it doesn't we cannot accept your submission. You MAY edit the containers or add additional ones if you like, but this MUST be clearly documented.

We have provided some containers to help build your application in either PHP, Go or Python, with a variety of persistence layers available to use.

### Technology

• Valid PHP 7.2, Go 1.8, or Python 3.6 code
• Persist data to either Postgres, Redis, or MongoDB (in the provided containers).
  • Postgres connection details:
    • host: postgres
    • port: 5432
    • dbname: hellofresh
    • username: hellofresh
    • password: hellofresh
  • Redis connection details:
    • host: redis
    • port: 6379
  • MongoDB connection details:
    • host: mongodb
    • port: 27017
• Use the provided docker-compose.yml file in the root of this repository. You are free to add more containers to this if you like.

Instructions

1. Clone this repository.

• Create a new branch called dev.
• Run docker-compose up -d to start the development environment.
  • If you want to use Go, uncomment the Go container in the docker-compose.yml file. Add the commands you need in there to execute the application.
  • If you want to use Python, uncomment the Python container in the docker-compose.yml file first. Add the commands you need in there to execute the application.
• Visit http://localhost to see the contents of the web container and develop your application.
• Create a pull request from your dev branch to the master branch. This PR should contain setup instructions for your application and a breakdown of the technologies & packages you chose to use, why you chose to use them, and the design decisions you made.
• Reply to the thread you're having with our HR department telling them we can start reviewing your code.

Requirements

We'd like you to build a simple Recipes API. The API MUST conform to REST practices and MUST provide the following functionality:

• List, create, read, update, and delete Recipes
• Search recipes
• Rate recipes

Endpoints

Your application MUST conform to the following endpoint structure and return the HTTP status codes appropriate to each operation. Endpoints specified as protected below SHOULD require authentication to view. The method of authentication is up to you.

Recipes

Name	Method	URL	Protected
List	GET	/recipes	✘
Create	POST	/recipes	✓
Get	GET	/recipes/{id}	✘
Update	PUT/PATCH	/recipes/{id}	✓
Delete	DELETE	/recipes/{id}	✓
Rate	POST	/recipes/{id}/rating	✘

An endpoint for recipe search functionality MUST also be implemented. The HTTP method and endpoint for this MUST be clearly documented.

Schema

• Recipe
  • Unique ID
  • Name
  • Prep time
  • Difficulty (1-3)
  • Vegetarian (boolean)

Additionally, recipes can be rated many times from 1-5 and a rating is never overwritten.

If you need a more visual idea of how the data should be represented, take a look at one of our recipe cards.

Evaluation criteria

These are some aspects we pay particular attention to:

• You MUST use packages, but you MUST NOT use a web-app framework or microframework. That is, you can use symfony/dependency-injection but not symfony/symfony.
• Your application MUST run within the containers. Please provide short setup instructions.
• The API MUST return valid JSON and MUST follow the endpoints set out above.
• You MUST write testable code and demonstrate unit testing it (for clarity, PHPUnit is not considered a framework as per the first point above. We encourage you to use PHPUnit or any other kind of testing framework).
• You SHOULD pay attention to best security practices.
• You SHOULD follow SOLID principles where appropriate.
• You do NOT have to build a UI for this API.

The following earn you bonus points:

• Your answers during code review
• An informative, detailed description in the PR
• Setup with a one liner or a script
• Content negotiation
• Pagination
• Using any kind of Database Access Abstraction
• Other types of testing - e.g. integration tests
• Following the industry standard style guide for the language you choose to use - PSR-2, gofmt, etc.
• A git history (even if brief) with clear, concise commit messages.

---

Good luck!