Building a Native Android Kotlin SDK for OpenClaw Rating API

Introduction

OpenClaw’s Rating API is a powerful, cloud‑native service that aggregates user‑generated ratings for products, movies, books, and more. While the API is language‑agnostic, Android developers benefit from a dedicated Kotlin SDK that abstracts HTTP plumbing, token refresh logic, and error handling. This guide walks you through every step—from setting up your Android Studio project to publishing the SDK on Maven Central—so you can ship a reliable rating feature in days, not weeks.

For a broader view of how UBOS empowers developers to host and scale AI‑driven services, check out the OpenClaw hosting on UBOS page.

Prerequisites

• Android Studio Flamingo (or newer) with Kotlin support.
• An active UBOS homepage account that provides an OpenClaw API key.
• Basic familiarity with Gradle, Coroutines, and Android Jetpack components.
• Optional: Knowledge of Enterprise AI platform by UBOS if you plan to integrate additional AI services later.

Project Setup

Adding Gradle Dependencies

Open your build.gradle.kts (or build.gradle) file and add the following Maven repository and SDK dependency:

repositories {
    mavenCentral()
    // Optional: JitPack for preview builds
    maven { url = uri("https://jitpack.io") }
}

dependencies {
    implementation("com.ubos:openclaw-sdk:1.0.0")
    // Kotlin Coroutines support
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.7.3")
}

Configuring the SDK Module

Create a dedicated Kotlin module named openclaw-sdk to keep the SDK isolated from UI code. This approach aligns with the Workflow automation studio philosophy of modular, reusable components.

1. File → New → New Module → Kotlin Library.
2. Move the build.gradle.kts snippet above into the new module’s Gradle file.
3. Expose the SDK via a public API surface (e.g., OpenClawClient class).

Authentication

OpenClaw uses API‑key authentication combined with short‑lived JWT tokens for enhanced security. Store the API key in local.properties (never commit it to VCS) and let the SDK handle token refresh automatically.

Step‑by‑Step Token Management

• Read the API key at runtime using BuildConfig.OPENCLAW_API_KEY.
• Initialize OpenClawAuthProvider with the key.
• The provider fetches a JWT from /auth/token and caches it in EncryptedSharedPreferences (see About UBOS for security best practices).

val authProvider = OpenClawAuthProvider(BuildConfig.OPENCLAW_API_KEY)
val client = OpenClawClient(authProvider)

When the token expires, the SDK transparently retries the request after refreshing the token, eliminating boilerplate code in your UI layer.

Request Handling

All API calls are exposed as suspend functions, making them perfect candidates for Kotlin Coroutines. Below is a typical rating submission flow.

suspend fun submitRating(
    productId: String,
    userId: String,
    score: Int
): RatingResponse {
    val request = RatingRequest(
        productId = productId,
        userId = userId,
        score = score
    )
    return client.submitRating(request)
}

Error Handling & Retries

Network failures, rate limits, and validation errors are wrapped in a sealed class OpenClawResult. Use when expressions to branch logic cleanly.

when (val result = submitRating(...)) {
    is OpenClawResult.Success -> { /* handle success */ }
    is OpenClawResult.ApiError -> { /* inspect error.code */ }
    is OpenClawResult.NetworkError -> {
        // Exponential back‑off retry
        retryWithBackoff { submitRating(...) }
    }
}

For advanced retry policies, integrate the UBOS templates for quick start that include a ready‑made RetryPolicy class.

Android Best Practices

Threading with Coroutines

Never block the main thread. Launch API calls inside viewModelScope or a dedicated Dispatchers.IO coroutine. This keeps UI responsive and aligns with the AI marketing agents pattern of asynchronous processing.

class RatingViewModel : ViewModel() {
    private val _state = MutableLiveData()
    val state: LiveData = _state

    fun rate(productId: String, score: Int) {
        viewModelScope.launch {
            _state.value = RatingUiState.Loading
            val result = repository.submitRating(productId, score)
            _state.value = result.toUiState()
        }
    }
}

Using LiveData / Flow

Expose the SDK’s Flow<RatingResponse> directly from a repository layer. UI components can then collect or observe without manual threading.

fun ratingFlow(productId: String): Flow =
    client.ratingUpdates(productId)
        .flowOn(Dispatchers.IO)

Security Considerations

• Never hard‑code API keys; use gradle.properties and BuildConfig.
• Store JWTs in EncryptedSharedPreferences or the Android Keystore.
• Enable UBOS partner program to receive security patches for the SDK.
• Validate all server responses against a JSON schema (the SDK includes a built‑in validator).

Referencing the iOS Swift SDK Guide

UBOS maintains a parallel iOS Swift SDK that mirrors the Android Kotlin SDK’s API surface. By following the same naming conventions and authentication flow, you can achieve cross‑platform consistency and share business logic between Android and iOS projects.

Developers are encouraged to read the iOS guide (available in the mobile SDK series) to understand how the same OpenClawClient class behaves on Swift, making it trivial to port rating features across platforms.

Testing the SDK

Robust testing ensures that rating submissions behave correctly under network fluctuations and API version changes.

Unit Tests

Leverage MockWebServer to simulate OpenClaw endpoints. The SDK’s interfaces are designed for dependency injection, allowing you to inject a mock OpenClawApi implementation.

@Test fun `submitRating returns success`() = runBlocking {
    val mockResponse = MockResponse()
        .setBody("{\"ratingId\":\"12345\"}")
        .setResponseCode(200)
    mockWebServer.enqueue(mockResponse)

    val client = OpenClawClient(mockAuthProvider, mockWebServer.url("/"))
    val result = client.submitRating(RatingRequest(...))

    assertTrue(result is OpenClawResult.Success)
}

Instrumented Tests

Run UI‑level tests on an emulator using Espresso to verify that the RatingViewModel updates LiveData correctly after a successful API call.

For a full test suite template, explore the AI SEO Analyzer template, which includes both unit and instrumented test configurations.

Publishing the SDK

Once your SDK passes all tests, you can share it with the Android community via Maven Central or JitPack.

Maven Central

1. Sign up for a Sonatype OSSRH account.
2. Configure publishing block in build.gradle.kts with GPG signing.
3. Run ./gradlew publishToMavenCentral.

JitPack (quick start)

If you prefer a lighter workflow, push your SDK repository to GitHub and reference it via JitPack:

implementation("com.github.yourname:openclaw-sdk:Tag")

For a step‑by‑step JitPack guide, see the GPT-Powered Telegram Bot example, which demonstrates the same publishing pipeline.

Conclusion

Building a native Android Kotlin SDK for the OpenClaw Rating API is a straightforward process when you follow a modular architecture, leverage Kotlin Coroutines, and respect Android security best practices. By reusing the same design patterns as the iOS Swift SDK, you achieve true cross‑platform parity, reduce maintenance overhead, and accelerate time‑to‑market for rating‑driven experiences.

Ready to explore more AI‑enhanced SDKs? Dive into the AI Video Generator template or start a new project with the Web app editor on UBOS. Happy coding!