baet-api-golang

BAET-API-Server-Golang

BAET.no API Server using Golang

Prerequisites

In order to build and run this app you need to have a couple of things installed:

• The Go SDK
• An IDE for the development, like Atom or IntelliJ/Goland
• The Docker Toolbox or native Docker, whatever you prefer. See Docker and Docker-Compose

Building the App

Clone this repo

  # clone this repo  
$ git clone https://github.com/zeusbaba/cloud-native-apps  
$ cd baet-api-golang  

Prepare env-vars

WARNING This APP requires a MongoDB instance to connect to!!!
You can either get yourself a free instance via mLab
or just follow the instructions in docker-compose related section below.

To be able to RUN this app, you must prepare env-vars.
No worries, this example-file got you covered!

# copy the example template  
$ cp docker_vars_env-example docker_vars.env  

# open the file and set the values accordingly. it's self-explanatory  
$ vim docker_vars.env    

Run the App in localhost

  # automatically import env-vars you've prepared in prev step    
$ source import-env-vars.sh

  # run the App  
$ go run baet-api.go

# build & run it
$ go build baet-api.go
$ ./baet-api

Now you can access your API by using this Postman collection

Containerization with Docker

Building, publishing and running via Docker and Docker-Compose:

# set env vars for ease-of-use
# NOTE! please just replace 'zeusbaba' with your user  
$ export dockerhubUser=zeusbaba \
  export appName=baet-api-golang \
  export appSecrets=baet-api-secrets \
  export appVersion=1.0.1
$ export dockerImage=${dockerhubUser}/${appName}:${appVersion}
  
  # required for compatibility
$ GOOS=linux GOARCH=amd64 go build

## using Docker!!!       
# build a docker image  
$ docker build \
  -t ${dockerImage} \
  --rm --no-cache .    
$ docker images  	
# (optional) publish the image to docker hub  
$ docker push ${dockerImage}  

# (optional) run the docker image locally    
$ docker run \
	-p 4042:4042 \
	--env-file ./${appSecrets}/docker_vars.env \
	${dockerImage}  


## using Docker Compose!!! 
$ docker-compose up --build 

  # NOTE: in linux-env you might have permission problems with 'docker-data-*' folders      
  # to fix; stop docker-compose, set permissions as below, then run docker-compose again.    
$ sudo chown 1001:1001 -R docker-data-*  

  # shut it down 
$ docker-compose down   

Deploying and Running in Kubernetes (k8s)

We already have created docker_vars.env file
which contains all env-vars which is required for our app to run!

To be able to inject this file into k8s cluster, we can either use secrets or configmap
As you've seen docker_vars.env file contains sensitive data like AUTH_SECRET, therefore it's recommended to use secrets in k8s.

k8s secrets

Thus, we must create k8s-secrets to inject our env-vars from this file.

$ export appSecrets=baet-api-secrets
  
  # create using secrets   
$ kubectl create secret \
    generic ${appSecrets} \
    --from-file=${appSecrets}/docker_vars.env
  
  # validate its creation
$ kubectl get secrets     
$ kubectl get secret ${appSecrets} -o yaml  
  # if you want to delete  
$ kubectl delete secret ${appSecrets}

minikube

Please make sure that you already have installed minikube
We'll use local k8s-cluster with minikube.

After you've installed minikube, run the basic commands for preparation:

# start minikube  
$ minikube start  
# using dockerd inside minikube
$ eval $(minikube docker-env)  

# you must rebuild app's docker image so that minikube acquires it
$ docker build \
  -t ${dockerImage} \
  --rm --no-cache .

TODO: add k8s-pods, deployments, service, ingress