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Version: 2.0.0

Sample URL Shortener App (Golang)

Introduction

🪄 Dive into the world of URL shorteners and see how seamlessly Keploy integrates with Gin and MongoDB. Buckle up, it's gonna be a fun ride! 🎢

🛠️ Platform-Specific Requirements for Keploy

Below is a table summarizing the tools needed for both native and Docker installations of Keploy on MacOS, Windows, and Linux:

Operating SystemWithout DockerDocker InstallationPrerequisites
MacOS MacOSNot SupportedSupportedDocker Desktop version must be 4.25.2 or above
Windows WindowsSupportedSupported- Use WSL wsl --install
- Windows 10 version 2004 and higher (Build 19041 and higher) or Windows 11
Linux LinuxSupportedSupportedLinux kernel 5.15 or higher

On MacOS and Windows, additional tools are required for Keploy due to the lack of native eBPF support.

Quick Installation

Let's get started by setting up the Keploy alias with this command:

 curl --silent -O -L https://keploy.io/install.sh && source install.sh

You should see something like this:

       ▓██▓▄
▓▓▓▓██▓█▓▄
████████▓▒
▀▓▓███▄ ▄▄ ▄ ▌
▄▌▌▓▓████▄ ██ ▓█▀ ▄▌▀▄ ▓▓▌▄ ▓█ ▄▌▓▓▌▄ ▌▌ ▓
▓█████████▌▓▓ ██▓█▄ ▓█▄▓▓ ▐█▌ ██ ▓█ █▌ ██ █▌ █▓
▓▓▓▓▀▀▀▀▓▓▓▓▓▓▌ ██ █▓ ▓▌▄▄ ▐█▓▄▓█▀ █▓█ ▀█▄▄█▀ █▓█
▓▌ ▐█▌ █▌


Keploy CLI

Available Commands:
example Example to record and test via keploy
generate-config generate the keploy configuration file
record record the keploy testcases from the API calls
test run the recorded testcases and execute assertions
update Update Keploy

Flags:
--debug Run in debug mode
-h, --help help for keploy
-v, --version version for keploy

Use "keploy [command] --help" for more information about a command.

🎉 Wohoo! You are all set to use Keploy.

Clone the sample URL shortener app 🧪

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

Installation 📥

There are 2 ways you can run this sample application.

Using Docker Compose 🐳

We will be using Docker compose to run the application as well as MongoDb on Docker container.

Lights, Camera, Record! 🎥

Fire up the application and mongoDB instance with Keploy. Keep an eye on the two key flags: -c: Command to run the app (e.g., docker compose up).

--container-name: The container name in the docker-compose.yml for traffic interception.

keploy record -c "docker compose up" --container-name "ginMongoApp"

Getting logs like this? Perfect! 👌

Keploy Record Test case

🔥 Challenge time! Generate some test cases. How? Just make some API calls. Postman, Hoppscotch or even curl - take your pick!

Let's make URLs short and sweet:

Generate shortened url

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

Here's a peek of what you get:

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

🎉 Woohoo! With a simple API call, you've crafted a test case with a mock! Dive into the Keploy directory and feast your eyes on the newly minted test-1.yml and mocks.yml

version: api.keploy.io/v1beta2
kind: Http
name: test-1
spec:
metadata: {}
req:
method: POST
proto_major: 1
proto_minor: 1
url: http://localhost:8080/url
header:
Accept: "*/*"
Content-Length: "33"
Content-Type: application/json
Host: localhost:8080
User-Agent: curl/7.77.0
body: |-
{
"url": "https://google.com"
}
body_type: ""
resp:
status_code: 200
header:
Content-Length: "65"
Content-Type: application/json; charset=utf-8
Date: Sun, 01 Oct 2023 15:15:47 GMT
body: '{"ts":1696173347979970488,"url":"http://localhost:8080/Lhr4BWAi"}'
body_type: ""
status_message: ""
proto_major: 0
proto_minor: 0
objects: []
assertions:
noise:
- header.Date
created: 1696173352

this is how the generated mock.yml will look like:

version: api.keploy.io/v1beta2
kind: Mongo
name: mocks
spec:
metadata:
operation: '{ OpMsg flags: 0, sections: [{ SectionSingle msg: {"update":"url-shortener","ordered":true,"writeConcern":{"w":"majority"},"lsid":{"id":{"$binary":{"base64":"eRaUQwDxR2qw3Jcbpn0Gfw==","subType":"04"}}},"$db":"keploy"} }, { SectionSingle identifier: updates , msgs: [ {"q":{"_id":"Lhr4BWAi"},"u":{"$set":{"_id":"Lhr4BWAi","created":{"$date":{"$numberLong":"1696173347975"}},"updated":{"$date":{"$numberLong":"1696173347975"}},"url":"https://google.com"}},"upsert":true} ] }], checksum: 0 }'
requests:
- header:
length: 301
requestId: 11
responseTo: 0
Opcode: 2013
message:
flagBits: 0
sections:
- '{ SectionSingle msg: {"update":"url-shortener","ordered":true,"writeConcern":{"w":"majority"},"lsid":{"id":{"$binary":{"base64":"eRaUQwDxR2qw3Jcbpn0Gfw==","subType":"04"}}},"$db":"keploy"} }'
- '{ SectionSingle identifier: updates , msgs: [ {"q":{"_id":"Lhr4BWAi"},"u":{"$set":{"_id":"Lhr4BWAi","created":{"$date":{"$numberLong":"1696173347975"}},"updated":{"$date":{"$numberLong":"1696173347975"}},"url":"https://google.com"}},"upsert":true} ] }'
checksum: 0
read_delay: 41060962050
responses:
- header:
length: 60
requestId: 14
responseTo: 11
Opcode: 2013
message:
flagBits: 0
sections:
- '{ SectionSingle msg: {"n":{"$numberInt":"1"},"nModified":{"$numberInt":"1"},"ok":{"$numberDouble":"1.0"}} }'
checksum: 0
read_delay: 2506709
created: 1696173347

Time to perform more API magic! Follow the breadcrumbs... or the shortened URLs:

Redirect to original url from shortened url

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

Or just type http://localhost:8080/Lhr4BWAi in your browser. Your choice!

Spotted the new test and mock files in your project? High five! 🙌

Sample Keploy Test case and Mock for Gin MongoDB

Want to see if everything works as expected?

Run Tests 🏃‍♀️

Time to put things to the test 🧪

keploy test -c "docker compose up" --container-name "ginMongoApp" --delay 10

The --delay flag? Oh, that's just giving your app a little breather (in seconds) before the test cases come knocking.

Your results should be looking all snazzy, like this:

Sample Keploy Test Result Gin MongoDB

Did you spot that the ts (timestamp) is showing some differences? Yep, time has a way of doing that! 🕰️

Worry not, just add the ever-changing fields (like our ts here) to the noise parameter to dodge those assertions.

Pro tip: Add body.ts to noise in test-x.yaml.

Adding Noise to Test case Gin MongoDB

Run that keploy record command once more and watch as everything falls into place with all tests passing!🌟

Final thoughts? Dive deeper! Try different API calls, tweak the DB response in the mocks.yml, or fiddle with the request or response in test-x.yml. Run the tests again and see the magic unfold!✨👩‍💻👨‍💻✨

Wrapping it up 🎉

Congrats on the journey so far! You've seen Keploy's power, flexed your coding muscles, and had a bit of fun too! Now, go out there and keep exploring, innovating, and creating! Remember, with the right tools and a sprinkle of fun, anything's possible.😊🚀

Happy coding! ✨👩‍💻👨‍💻✨


Running App Locally on Linux/WSL 🐧

We'll be running our sample application right on Linux, but just to make things a tad more thrilling, we'll have the database (mongoDB) chill on Docker. Ready? Let's get the party started!🎉

If you are using WSL on Windows then use below to start wsl in the user's home directory:

wsl ~

First things first, update the MongoDB URL to localhost:27017 on line 21 of our trusty main.go file.

Linux change Gin MongoDB

🍃 Kickstart MongoDB

Let's breathe life into your mongo container. A simple spell should do the trick:

docker compose up mongo

📼 Recording Time!

Ready, set, record! Here's how:

keploy record -c "go run main.go handler.go"

Keep an eye out for the -c flag! It's the command charm to run the app. Whether you're using go run main.go handler.go or the binary path like ./test-app-url-shortener, it's your call. If you're seeing logs that resemble the ones below, you're on the right track:

Keploy Record Test case

Alright! With the app alive and kicking, let's weave some test cases. Making some API calls! Postman, Hoppscotch, or the classic curl - pick your wand.

Generate shortened url

✨ A pinch of URL magic:

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

And... voila! A shortened URL appears:

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

Give yourself a pat on the back! With that simple spell, you've conjured up a test case with a mock! Explore the Keploy directory and you'll discover your handiwork in test-1.yml and mocks.yml.

version: api.keploy.io/v1beta2
kind: Http
name: test-1
spec:
metadata: {}
req:
method: POST
proto_major: 1
proto_minor: 1
url: http://localhost:8080/url
header:
Accept: "*/*"
Content-Length: "33"
Content-Type: application/json
Host: localhost:8080
User-Agent: curl/7.77.0
body: |-
{
"url": "https://google.com"
}
body_type: ""
resp:
status_code: 200
header:
Content-Length: "65"
Content-Type: application/json; charset=utf-8
Date: Sun, 01 Oct 2023 15:15:47 GMT
body: '{"ts":1696173347979970488,"url":"http://localhost:8080/Lhr4BWAi"}'
body_type: ""
status_message: ""
proto_major: 0
proto_minor: 0
objects: []
assertions:
noise:
- header.Date
created: 1696173352

this is how the generated mock.yml will look like:

version: api.keploy.io/v1beta2
kind: Mongo
name: mocks
spec:
metadata:
operation: '{ OpMsg flags: 0, sections: [{ SectionSingle msg: {"update":"url-shortener","ordered":true,"writeConcern":{"w":"majority"},"lsid":{"id":{"$binary":{"base64":"eRaUQwDxR2qw3Jcbpn0Gfw==","subType":"04"}}},"$db":"keploy"} }, { SectionSingle identifier: updates , msgs: [ {"q":{"_id":"Lhr4BWAi"},"u":{"$set":{"_id":"Lhr4BWAi","created":{"$date":{"$numberLong":"1696173347975"}},"updated":{"$date":{"$numberLong":"1696173347975"}},"url":"https://google.com"}},"upsert":true} ] }], checksum: 0 }'
requests:
- header:
length: 301
requestId: 11
responseTo: 0
Opcode: 2013
message:
flagBits: 0
sections:
- '{ SectionSingle msg: {"update":"url-shortener","ordered":true,"writeConcern":{"w":"majority"},"lsid":{"id":{"$binary":{"base64":"eRaUQwDxR2qw3Jcbpn0Gfw==","subType":"04"}}},"$db":"keploy"} }'
- '{ SectionSingle identifier: updates , msgs: [ {"q":{"_id":"Lhr4BWAi"},"u":{"$set":{"_id":"Lhr4BWAi","created":{"$date":{"$numberLong":"1696173347975"}},"updated":{"$date":{"$numberLong":"1696173347975"}},"url":"https://google.com"}},"upsert":true} ] }'
checksum: 0
read_delay: 41060962050
responses:
- header:
length: 60
requestId: 14
responseTo: 11
Opcode: 2013
message:
flagBits: 0
sections:
- '{ SectionSingle msg: {"n":{"$numberInt":"1"},"nModified":{"$numberInt":"1"},"ok":{"$numberDouble":"1.0"}} }'
checksum: 0
read_delay: 2506709
created: 1696173347

Time to perform more API magic! Follow the breadcrumbs... or the shortened URLs:

Redirect to original url from shortened url

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

Or just type http://localhost:8080/Lhr4BWAi in your browser. Your choice!

Spotted the new test and mock files in your project? High five! 🙌

Sample Keploy Test case and Mock for Gin MongoDB

Want to see if everything works as expected?

🏃‍♀️ Run Tests

Time to put things to the test 🧪

keploy test -c "docker compose up" --container-name "ginMongoApp" --delay 10

The --delay flag? Oh, that's just giving your app a little breather (in seconds) before the test cases come knocking.

Your results should be looking all snazzy, like this:

Sample Keploy Test Result Gin MongoDB

Did you spot that the ts (timestamp) is showing some differences? Yep, time has a way of doing that! 🕰️

Worry not, just add the ever-changing fields (like our ts here) to the noise parameter to dodge those assertions.

Pro tip: Add body.ts to noise in test-x.yaml.

Adding Noise to Test case Gin MongoDB

Run that keploy test command once more and watch as everything falls into place with all tests passing! 🌟

Final thoughts? Dive deeper! Try different API calls, tweak the DB response in the mocks.yml, or fiddle with the request or response in test-x.yml. Run the tests again and see the magic unfold! ✨👩‍💻👨‍💻✨

🎉 Wrapping it up

Congrats on the journey so far! You've seen Keploy's power, flexed your coding muscles, and had a bit of fun too! Now, go out there and keep exploring, innovating, and creating! Remember, with the right tools and a sprinkle of fun, anything's possible. 😊🚀

Hope this helps you out, if you still have any questions, reach out to us .

Contact Us

If you have any questions or need help, please feel free to reach out to us at hello@keploy.io or reach out us on Slack or open a discussion on GitHub Discussion