Logixboard Backend Engineering Take-Home Challenge

Thanks for applying to Logixboard! The next step in our process is a coding challenge. Our goals with this step in the process are the following:

To assess your ability to problem solve and develop a well-engineered solution to a user need.
To give you an opportunity to show creativity in how you solve a user need.
To give us a tool we can use for discussion and collaboration in our synchronous interviews.

We hope and expect that this exercise should take about two hours to complete. If it takes you a bit more than that, that's okay, and you don't need to tell us. If it takes you a lot more than that, please let us know so we can reevaluate the exercise for future candidates.

Assignment

For this challenge, we are asking you to implement some API's on a bootstrapped express server.

If you are not comfortable with NodeJS/Typescript, feel free to use your own stack.

Product Context

Logixboard is a customer engagement tool for freight forwarders to provide their customers with visibility into their supply chains. You've probably gotten an intro at this point on what a Freight Forwarder is, but in case you haven't: Freight Forwarders are the project managers of the logistics world. They don't own any planes, trains, or boats. They are just really good at coordinating with all the actors to make sure their customers' freight gets from point A to B.

Logixboard's offering has grown into being the primary communication hub between freight forwarders and their customers. At the core of our product we process large amounts of data. The goal of this assignment draws inspiration from work we've done.

Data Ingress APIs

One of the key components to our system is accepting and storing data in an accurate manner. We've outlined two POST APIs for you /shipment and /organization. Please implement the logic for these APIs. Both should insert the object if it's not already present, and update it if it's already present.

A Shipment, as you may have guessed, is some items being moved from A to B. A Shipment can have zero to many Organizations associated with it. An Organization may be the party who is shipping the items, receiving the items, or paying for the item. It's important to know which Orgs are involved with a given shipment. Tracking these Shipment to Org relationships accurately is key in storing the data.

The data model is fairly simple in what you'll receive. You can inspect the data in messages.ts to see what they look like. Each message is a complete snapshot of the object at that time. Thus, you are receiving ALL the data for a given object in each message, not just what has changed. Don't worry about tracking intermediate states or object history, we only care about the most up to date view of a given object.

Your API should save the given object to maintain accurate data for later access. Feel free to use a persistence layer of your choosing that satisfies the requirements.

Running npm run send will hit the appropriate API given the message type. You may use this to test your API.

Note, as demonstrated in the example messages, that an Organization's code can change over time!

Data Egress APIS

We'd like to create some APIs that serve the data for our users and provide some value! Implement the /organizations/:id API so we can retrieve an Organization by its unique ID.

We'd also like to implement /shipments/:referenceId that returns a shipment and its related organizations in the following format:

{
   "type": "SHIPMENT",
   "referenceId": "S00001175",
   "organizations": [
      {
         "type": "ORGANIZATION",
         "id": "99f2535b-3f90-4758-8549-5b13c43a8504",
         "code": "BOG"
      },
      {
         "type": "ORGANIZATION",
         "id": "34f195b5-2aa1-4914-85ab-f8849f9b541a",
         "code": "FMT"
      }
   ],
   "transportPacks": {
      "nodes": [
         {
            "totalWeight": {
            "weight": "0",
            "unit": "KILOGRAMS"
            }
         }
      ]
   }
}

Weight aggregation

You may have noticed that each Shipment has an array of Transport Packs associated with it. Our product team has asked for us to provide that aggregated data over all Shipments we've now stored.

Your last task is to design and implement an API that allows us to see the total weight of all the Transport Packs in all shipments. We need to be able to specify what units are desired for the aggregated number. Since there are mixed units we'll need to convert where necessary.

Setup

Dependencies

This app was built with Node.js 15, but it should work with most modern versions of Node.js. If you run into any hiccups start by making sure you're on Node 15. We encourage the use of a tool like nvm to manage multiple versions and make sure you're running the correct one.

To install dependencies:

npm install

To start the development server:

npm run start

To run the test script:

npm run send

Submission

When you are complete, please submit in one of the following ways:

Compress the entire directory into any commonly used compression format and return it via email
Send us a link to a publicly available repository with the code.

We will assess your submission and follow up with next steps.

LeoCourbassier/be-challenge