Kotlin Screenshot API Quick Start
Add the SnapAPI Kotlin SDK to your Gradle build file and initialize the client in your application module. The Kotlin SDK is built on coroutines, making it natural to call the screenshot endpoint from a suspend function without blocking the calling coroutine. Initialize the SnapApiClient with the API key loaded from your application's configuration, and call the screenshot suspend function with a ScreenshotOptions data class configured with the target URL, format, viewport width, and full-page flag.
import io.snapapi.SnapApiClient
import io.snapapi.ScreenshotOptions
val client = SnapApiClient(apiKey = System.getenv("SNAPAPI_KEY"))
suspend fun captureScreenshot(url: String): ByteArray {
val result = client.screenshot(
ScreenshotOptions(
url = url,
format = "png",
fullPage = true,
width = 1280
)
)
return result.image
}
Kotlin Coroutines for Concurrent Screenshot Capture
Kotlin coroutines make concurrent screenshot capture across multiple URLs straightforward and readable. Use async builders within a coroutineScope to launch concurrent screenshot captures, and use a Semaphore from the coroutines library to limit the number of simultaneous SnapAPI calls to a value that respects your plan's rate limit. The structured concurrency model ensures that all concurrent captures complete before the outer coroutineScope returns, with exceptions from any individual capture propagated correctly to the calling coroutine for centralized error handling.
import kotlinx.coroutines.*
import kotlinx.coroutines.sync.Semaphore
import kotlinx.coroutines.sync.withPermit
suspend fun captureAll(urls: List, concurrency: Int = 5): List> {
val sem = Semaphore(concurrency)
return coroutineScope {
urls.map { url ->
async {
sem.withPermit {
runCatching { client.screenshot(ScreenshotOptions(url = url)).image }
}
}
}.awaitAll()
}
}
Ktor Server Screenshot API Endpoint
Ktor server applications exposing screenshot functionality define a route that extracts the URL query parameter, validates it, calls the SnapAPI suspend function using Ktor's call.application.launch in the IO dispatcher, and responds with the image bytes and a Content-Type: image/png header. Configure Ktor's rate limiting plugin using the rate-limit module to enforce per-client request limits that prevent individual clients from exhausting the SnapAPI plan limit. Use Ktor's caching infrastructure to store recently captured screenshots in a Cache-Control-aware response cache, returning cached screenshot bytes for repeat requests within the cache TTL without calling SnapAPI again. Deploy the Ktor application as a Docker container built with Gradle's application plugin, producing a self-contained JAR that runs on a minimal JRE base image in production Kubernetes environments.
Kotlin Flow-Based Screenshot Pipeline
Kotlin Flow provides a natural model for building screenshot processing pipelines that transform a stream of URLs into a stream of screenshot results with backpressure handling. Define a Flow of URL strings from a database query, message queue consumer, or in-memory list, then apply a flatMapMerge operator with a configured concurrency limit that calls the SnapAPI suspend function for each URL concurrently. Collect the resulting screenshot bytes in a terminal operator that stores each result in object storage, updating the associated database record with the storage key and capture timestamp. Use Flow's buffer operator between the screenshot capture stage and the storage stage to absorb processing rate differences, preventing slow storage writes from blocking new SnapAPI captures when the storage layer experiences temporary latency spikes.
Kotlin Multiplatform Screenshot API Integration
Kotlin Multiplatform projects that share business logic between JVM backend and Android clients can define the SnapAPI client interface in the common module and provide platform-specific implementations that use the appropriate HTTP client for each platform. The JVM implementation uses the Kotlin SDK's OkHttp or Ktor engine, while an Android implementation might use OkHttp directly with Android-specific configuration for certificate pinning and proxy settings. Shared coroutine-based screenshot service logic in the common module calls through the platform-specific client interface, enabling the same screenshot capture and caching logic to run on both the JVM backend and in Android test utilities that need to capture screenshots of rendered web content for automated visual testing of hybrid mobile applications.
Kotlin Screenshot API with Exposed ORM and PostgreSQL
Kotlin backend applications using JetBrains Exposed ORM for database access store SnapAPI screenshot results alongside structured metadata in PostgreSQL, enabling retrieval, cache invalidation, and usage tracking from the same database that stores application data. Define an Exposed table object for screenshot records with columns for the target URL, the capture timestamp, the S3 object key where the image is stored, and the requesting user ID for usage attribution. Wrap the screenshot capture and database insert in a single Exposed transaction so that the database record is only committed if both the SnapAPI call and the storage upload succeed, preventing orphaned database records that reference screenshots that were never successfully stored. Use Exposed's DSL query interface to implement a cache-aside pattern that checks for an existing non-expired screenshot record before calling SnapAPI, returning the stored S3 key on a cache hit and inserting a new record on a cache miss after the SnapAPI call completes.
Kotlin Screenshot API with Spring Boot and Coroutines
Kotlin Spring Boot applications benefit from combining Spring's dependency injection and configuration infrastructure with Kotlin's coroutine-based async model for SnapAPI calls. Annotate screenshot service methods with Spring's @Transactional for database operations and use Kotlin's suspend keyword for the SnapAPI HTTP call, composing the transactional and async concerns cleanly without callback nesting. Configure Spring Boot's WebFlux reactive web layer to handle screenshot API requests on a non-blocking event loop, calling the SnapAPI suspend function from a coroutineScope launched in the IO dispatcher to avoid blocking the reactive event loop during the HTTP call. Use Spring Boot's @Scheduled annotation with suspend function support provided by the spring-boot-starter-coroutines module to schedule periodic screenshot capture jobs that run as coroutines, enabling scheduled screenshot monitoring with the full expressive power of Kotlin coroutines in a standard Spring Boot application.
Kotlin Screenshot API Error Handling with Result Types
Kotlin's sealed class and Result type system enables expressive error handling for SnapAPI integrations that distinguishes between different error categories without relying on exception hierarchies. Define a sealed class hierarchy for SnapAPI results — ScreenshotSuccess containing the image bytes, RateLimitError containing the retry-after duration, InvalidUrlError containing the validation message, and NetworkError containing the underlying IO exception. Map SnapAPI SDK exceptions to this sealed class hierarchy in a single try-catch wrapper function, then use Kotlin's when expression to handle each case explicitly at the call site, making error handling paths visible and exhaustive. This approach integrates naturally with Kotlin coroutines — the mapping function is a suspend function, and when expressions over sealed classes in coroutine continuations are compiled to efficient state machine code without the overhead of exception handling for expected error cases like rate limiting.
Kotlin Screenshot API for Android Preview Generation
Android applications that display web content previews — link unfurling in messaging apps, bookmark thumbnails in browser apps, or website cards in social features — use SnapAPI to capture preview screenshots on the server side rather than loading full WebView instances on the device. The server-side Kotlin service calls SnapAPI when a user shares a URL or saves a bookmark, stores the screenshot in cloud storage, and returns the screenshot URL to the Android client, which loads the thumbnail image using Coil or Glide. This server-side screenshot approach eliminates the memory and performance overhead of rendering full web pages in Android WebViews for preview purposes, produces consistent screenshot quality regardless of the device's rendering capabilities, and enables screenshot reuse across multiple users who share or bookmark the same URL. The Kotlin SDK's coroutine-based interface integrates naturally with Android's coroutine-based architecture patterns — ViewModel.viewModelScope, Compose's rememberCoroutineScope, and Lifecycle.lifecycleScope all provide the coroutine scope needed to launch SnapAPI calls from Android UI components.
Kotlin Screenshot API Plan Selection
Kotlin applications integrating SnapAPI should select a plan based on projected monthly screenshot volume calculated from the number of URLs monitored, the capture frequency per URL, and the number of concurrent users triggering on-demand screenshot requests. The free tier provides two hundred monthly screenshots for development and proof-of-concept integrations. The nineteen-dollar starter plan with five thousand monthly screenshots suits Kotlin backend services handling moderate screenshot volumes for small production applications with a few hundred active users. The seventy-nine-dollar growth plan with fifty thousand monthly screenshots is appropriate for Kotlin microservices processing screenshot jobs at scale for production SaaS applications. Kotlin applications should implement screenshot credit tracking from the start, logging each SnapAPI call with the requesting user or feature context so that usage can be attributed accurately when evaluating plan upgrade timing and optimizing cache hit rates to reduce unnecessary screenshot captures.