kotlin-recaptcha-client

kotlin-recaptcha-client is a kotlin library for server side reCAPTCHA verification, it supports both recaptcha v2 and recaptcha v3.

"reCAPTCHA is a free CAPTCHA service that protects websites from spam and abuse."

• reCAPTCHA: https://www.google.com/recaptcha/about/
• Version: 1.1.0-beta
• License: MIT, see LICENSE

Installation

WIP

Basic Usage

For v2 client:

import com.wusatosi.recaptcha.v2.RecaptchaV2Client

val v2Client = RecaptchaV2Client.create("your site secret")
runBlocking {
    // RecaptchaV2Client.verify is a suspend function
    val result: Boolean = v2Client.verify(token)

    // ...
}
v2Client.close()

For v3 client:

import com.wusatosi.recaptcha.v3.RecaptchaV3Client

val v3Client = RecaptchaV3Client.create("your site secret")
runBlocking {
    // RecaptchaV3Client.verify is a suspend function
    val result: Double = v3Client.verify(token)

    // ...
}
v3Client.close()

Configuring the client

Domain verification

Both V2 Client and V3 Client can be configured to restrict access to the website/ apk package for which the captcha was solved. The domain name is not verified by default.

RecaptchaV2Client.create("your site secret") {
    // Website domain:
    allowDomain("wusatosi.com", "google.com")
    allowDomains(listOf("github.com", "localhost"))

    // APK package domain:
    allowDomain("com.wusatosi.test")
}

Score Threshold and Action Verification (v3 only)

For v3 client, you can config a score threshold for verification.

RecaptchaV3Client.create("your site secret") {
    scoreThreshold = 0.8
}

You can limit the scope of actions you would like to limit.

RecaptchaV3Client.create("your site secret") {
    limitedActions("login")
    limitedActions("interact", "publish")
}

You can also supply a lambda that produces a score threshold depending on which action is reported.

RecaptchaV3Client.create("your site secret") {
    mapActionToThreshold {
        when (it) {
            // a higher threshold to essential operations
            "login" -> 0.8
            // a lower threshold to non-essential operations
            "post" -> 0.5
            // We reject any other actions
            else -> 5.0
        }
    }
}

Contributing

Issues and pull requests are all always welcome

Uses:

• Kotlin-coroutines
• Ktor (http client)
• Gson

License

MIT