bot_detector

Bot Detector

What I did

I made a HTTP server that accepts any POST request (JSON) from multiple clients' websites. Each request forms part of a struct (for that particular visitor) that will be printed on the terminal in every POST request and when the struct is fully complete.

Frontend (JS)

I used XMLHttpRequest (XHR) API for sending (JSON) requests in 3 cases:

1. In the first time the user attempts to resize the window.
2. Every time the user tries to copy or paste from any field in the form.
3. When the user submits the form.

See the frontend code here index.html.

Example of JSON Requests

{
    "eventType": "resizingWindow",
    "websiteUrl": "https://ravelin.com",
    "sessionId":  "jGspdT-9cjpwBmqcfkKnkPn2DJS2",
    "beforeWidth": 1470 ,
    "beforeHeight": 830 ,
    "afterWidth": 830 ,
    "afterHeight": 830
}

{
  "eventType": "copyAndPaste",
  "websiteUrl": "https://ravelin.com",
  "sessionId": "jGspdT-9cjpwBmqcfkKnkPn2DJS2",
  "copiedorpaste": true,
  "formId": "inputCardNumber"
}

{
  "eventType": "timeTaken",
  "websiteUrl": "https://ravelin.com",
  "sessionId": "jGspdT-9cjpwBmqcfkKnkPn2DJS2",
  "time": 72, // seconds
}

Backend (GO)

At the backend I used GO standard packages to:

1. Serve index.html using http.HandleFunc() and template.ParseFiles() to capture the request and parse the html file.
2. Accept a POST request in JSON format using json.Unmarshal() function.
3. Map this JSON objects to our struct Data and insert it to a map, called users, where the key is the client sessionId and the value is our struct.
4. Print the struct at each stage of construction and at the end when it is completed.
5. Handling concurrent requests, since http.HandleFunc() is running in a goroutine functions so it can manage receiving multiple requests at the same time but we can't access out temporary database (our map users) so I created and a refrence instance from mutex = &sync.Mutex{} to protect the map from being accessed concurrency using mutex.Lock() and mutex.Unlock().

See the code here main.go

Testing

For more efficient and effective code and easy testing I created some unit tests and hole function test which can be run easliy through the terminal using code-test/$ go test server/testname_test.go server/main.go for separate tests or using code-test/$ go test.

I have 4 different tests:

1. basicFuncs_test.go which tests some basic functions like inserData() , getNewSessionId() and floatToStr().
2. handlerFuncs_test.go which tests the functions used to handle different JSON objects like submittingHandler(), copyAndPasteHandler() and resizingHandler().
3. httpHandlerFuncs_test.go which tests the fucntions used to handle HTTP POST and GET requests like eventHandler() and indexHandler()
4. overall_test.go which tests the over all functionality of the server in concurrent requests.