Coding Challenge

Design Rationale

Initially when I wrote the TCP server I had come up with a data structure like this


{
    "Package_Name": {
        Deps : [] // dependencies for this package
        ReqBy: [] // required by other packages
    }
}

I changed my mind however since the Index and Remove operations become pretty large and pretty complex. And hard to read. Also it didn't run as fast as I thought it would.

So I opted out for a simpler data model.

{
    "Package_Name": [] // deps for the package
}

Which meant that I use raw iteration to Remove and Add dependencies. This is less efficient then using the other data structure but my code was much simpler to read and understand. If we were able to use some libraries, I would have opted out to use leveldb or some other embedded database for all that nice persistence stuff.

Tests

I've added integration and unit tests.

server_test.go is where I spin up a real server and test its outputs, the "integration" tests

All other tests are simple unit tests.

Dockerfile run

I've included two docker files.

The default Dockerfile assumes you have go installed correctly. This uses the scratch image and produces a very small image because all that is in the container is the compiled go binary

The other file, Dockerfile.extra makes no assumptions at all except that you have docker installed This image is far larger.

Have Go installed

First Build using this command

CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o main

Then build image

docker build -t do-challenge .

Run the container!

docker run -p "8080:8080" do-challenge

Do NOT have Go installed

Build the image

docker build -f Dockerfile.extra . -t do-challenge

Run the container