Webservice to create GCE in Go

This is a basic go script to create a small Google Compute Engine instance by passing in username and password as the query parameter in the POST request.

The script will spin a new GCE instance by passing a startup script during boot. The startup script will create a new user and assigns a password from the query parameter and enables root and password authentication by modifying the sshd_config file.

Requirement

• The script requires go to be installed and the right paths set as part of the $PATH environment variable. Refer Go Installation doc to know more on this
• Google SDK to be installed and configured in the instance where the script will be run. The user should have necessary permission to create GCE instance.

End Points

The script has two endpoints

• GET /healthcheck
• POST /v1/instances/create

The GET end point just responds with a 200 response code and display a blank page to indicate the service is running

The POST end point takes two query parameters username and password, which will be assigned to the instance for login.

Note:

• The script creates a default instance of f1-micro family type. Make necessary changes in script if you want to customise instance type, image type, region, zone etc. ( Basically you can enhance it by creating additional query parameters and using it in the script )

Usage

Build

The first step is the build process where the go script will be compiled and an executable file gets created.

cd ~/go/src/go_gce

go build spin_gce.go

Run

Start the script by running the below command

go run spin_gce &

By default the script runs in port 3000.

GET

curl -X GET http://localhost:3000/healthcheck

Replace localhost with the corresponding Domain name or IP

POST

curl -X POST -F 'username=test' -F 'password=password123' http://localhost:3000/v1/instances/create

Replace localhost with the corresponding Domain name or IP. The IP address of the instance will be sent as response if the instance is created successfully