Golang Http Server Application

This repository was created to display a golang assignment. Contents of the assignment can be found in Golang_Assignment.pdf.

Content

• main.go
• Dockerfile
• go-app-deployment.yaml
• go-app-service.yaml

Go App Local Deployment

You can run this application locally having already installed golang on your local machine. Please reference https://go.dev/doc/install

You may have to initialize a go module before hand. Please reference https://go.dev/doc/install. In this instance a go.mod file is provided.

Once the golang installation is complete you can now run the main.go file provided.

  go run main.go

The http server should be running now on your local machine. To view the application running use your browser and type in the follow URL example.

  localhost:8080/?limit=10&sortKey=views

The application is set to listen on port 8080.

The limit value will display a certain amount of information from the queried URLs provided in the golang assignment file. In the example above the limit value is set to 10 so it will display 10 counts of information found in the URLs that are being queried.

The sortKey value has 2 valid values which are views and relevanceScore. Using any other value will display a message saying

 Invalid sortKey value, please try using views or relevanceScore

Once either views or relevanceScore is set it will display data obtained from the URLs in accending order of views or relevancescore depending on which one was provided.

Go App Minikube Deployment

To run the go application on a Minikube cluster make sure you have installed it correctly and with a container runtime. In my case I used docker. You can find more information on how to install minikube here: https://minikube.sigs.k8s.io/docs/start/

Once the minikube cluser is up and running you can use my image found in dockerhub

anthony0202/golang_http_server

If you would like to create your own image tag for your docker hub you can find the Dockerfile in this repo as well.

To create the image run:

docker build -t <your_repo>/<image-name> .

Make sure that your Dockerfile is located in your current directy in order for it to get built.

Once the image is ready you can now run:

kubectl create -f go-app-deployment.yaml

If you are using a custom image you will need to edit the go-app-deployment.yaml file.

This deployment has 3 replicas, if you want less or more pods you will need to edit the go-app-deployment.yaml as well.

Now that the deployment is up and running we need to expose the application, we do this by creating a NodePort service. The manifest for the service is also provided in this repo.

To create the service run:

kubectl create -f go-app-service.yaml

This will connect port 8080 of the pod to port 8080 of the service and expose it to the node on port 300007

Since the minikube cluster is a single node you can find the node ip by running:

minikube ip

Once you have the minikube ip you can access the application by running:

<minkube_ip>:30007/?limit=10&sortKey=views

Disclaimer

The main.go code is missing some error handlings when an invalid limit value is provided, such a negative integer or a string that cannot be converted to integer.