Gin Mongo Sample Application

Introduction

A sample url shortener app to test Keploy integration capabilities using Gin and mongoDB.

Setup URL shortener

git clone https://github.com/keploy/samples-go.git && cd samples-go/gin-mongo
go mod download

Installation

There are two methods to run the sample application using Keploy :-

Using Docker
Natively on Ubuntu/Windows(using WSL)

Running app using Docker

Keploy can be used on Linux & Windows through Docker, and on MacOS by the help of Colima

Create Keploy Alias

To establish a network for your application using Keploy on Docker, follow these steps.

If you're using a docker-compose network, replace keploy-network with your app's docker_compose_network_name below.

docker network create keploy-network

Then, create an alias for Keploy:

alias keploy='sudo docker run --pull always --name keploy-v2 -p 16789:16789 --network keploy-network --privileged --pid=host -it -v "$(pwd)":/files -v /sys/fs/cgroup:/sys/fs/cgroup -v /sys/kernel/debug:/sys/kernel/debug -v /sys/fs/bpf:/sys/fs/bpf -v /var/run/docker.sock:/var/run/docker.sock --rm ghcr.io/keploy/keploy'

Let's start the MongoDB Instance

Using the docker-compose file we will start our mongodb instance:-

docker-compose up -d

Alternatively, we can run docker run command to start our MongoDB Instance by using: -

sudo docker run --rm -p27017:27017 -d --network keploy-network --name mongoDb mongo

Now, we will create the docker image of our application:-

docker build -t gin-app:1.0 .

Capture the Testcases

keploy record -c "docker run -p 8080:8080 --rm --name ginMongoApp --network keploy-network gin-app:1.0"

Generate testcases

To genereate testcases we just need to make some API calls. You can use Postman, Hoppscotch, or simply curl

1. Generate shortned url

curl --request POST \
  --url http://localhost:8080/url \
  --header 'content-type: application/json' \
  --data '{
  "url": "https://google.com"
}'

this will return the shortened url.

{
  "ts": 1645540022,
  "url": "http://localhost:8080/Lhr4BWAi"
}

2. Redirect to original url from shortened url

curl --request GET \
  --url http://localhost:8080/Lhr4BWAi

or by querying through the browser http://localhost:8080/Lhr4BWAi Now, let's see the magic! 🪄💫

Now both these API calls were captured as a testcase and should be visible on the Keploy CLI. You should be seeing an app named keploy folder with the test cases we just captured and data mocks created.

Run the captured testcases

Now that we have our testcase captured, run the test file.

keploy test -c "sudo docker run -p 8080:8080 --rm --net keploy-network --name ginMongoApp gin-app:1.0" --delay 10

So no need to setup dependencies like mongoDB, web-go locally or write mocks for your testing.

The application thinks it's talking to mongoDB 😄

We will get output something like this:

TestRun

Go to the Keploy log to get deeper insights on what testcases ran, what failed. The ts is causing be failure during testing because it'll always be different.

Let's add Timestamp to Noisy field:

In test-1.yml and test-2.yml, go the noisefield and under -header.Data add the -body.ts on line number 37. Now, it's the time to run the test cases again.

keploy test -c "sudo docker run -p 8080:8080 --rm --net keploy-network --name MongoApp gin-app:1.0" --delay 10

This time all the test cases will pass.

Run app Natively on local machine

Keploy can be installed on Linux directly and on Windows with the help of WSL. Based on your system archieture, install the keploy latest binary release

1. AMD Architecture

curl --silent --location "https://github.com/keploy/keploy/releases/latest/download/keploy_linux_amd64.tar.gz" | tar xz -C /tmp

sudo mkdir -p /usr/local/bin && sudo mv /tmp/keploy /usr/local/bin && keploy

2. ARM Architecture

curl --silent --location "https://github.com/keploy/keploy/releases/latest/download/keploy_linux_arm64.tar.gz" | tar xz -C /tmp

sudo mkdir -p /usr/local/bin && sudo mv /tmp/keploy /usr/local/bin && keploy

Let's start the MongoDB Instance

Spin up your mongo container using

docker run --rm -p27017:27017 -d --name ginMongoApp mongo

Since, we are on the local machine the MongoDB URL will be localhost:27017. This needs to be updated on the on line 21 in main.go file

Capture the testcases

Now, we will create the binary of our application:-

go build

Once we have our binary file ready,this command will start the recording of API calls using ebpf:-

sudo -E keploy record -c "./test-app-url-shortener"

Make API Calls using Hoppscotch, Postman or cURL command. Keploy with capture those calls to generate the test-suites containing testcases and data mocks.

Generate testcases

To generate testcases we just need to make some API calls. You can use Postman, Hoppscotch, or simply curl

1. Generate shortened url

curl --request POST \
  --url http://localhost:8080/url \
  --header 'content-type: application/json' \
  --data '{
  "url": "https://google.com"
}'

this will return the shortened url. The ts would automatically be ignored during testing because it'll always be different.

{
  "ts": 1645540022,
  "url": "http://localhost:8080/Lhr4BWAi"
}

2. Redirect to original url from shortened url

curl --request GET \
  --url http://localhost:8080/Lhr4BWAi

or by querying through the browser http://localhost:8080/Lhr4BWAi

You'll be able to see new test file and mock file generated in your project codebase locally.

Run the Test Mode

Run this command on your terminal to run the testcases and generate the test coverage report:-

sudo -E keploy test -c "./test-app-url-shortener" --delay 10

Note: If delay value is not defined, by default it would be 5.