GCP client for Google AI platform

gradle/libs.versions.toml

@@ -51,6 +51,8 @@ kotlinx-coroutines-reactive = { module = "org.jetbrains.kotlinx:kotlinx-coroutin
 ktor-utils = { module = "io.ktor:ktor-utils", version.ref = "ktor" }
 ktor-http = { module = "io.ktor:ktor-http", version.ref = "ktor" }
 ktor-client ={ module = "io.ktor:ktor-client-core", version.ref = "ktor" }
+ktor-client-content-negotiation ={ module = "io.ktor:ktor-client-content-negotiation", version.ref = "ktor" }
+ktor-client-serialization = { module = "io.ktor:ktor-serialization-kotlinx-json", version.ref = "ktor" }
 ktor-client-cio = { module = "io.ktor:ktor-client-cio", version.ref = "ktor" }
 ktor-client-js = { module = "io.ktor:ktor-client-js", version.ref = "ktor" }
 ktor-client-winhttp = { module = "io.ktor:ktor-client-winhttp", version.ref = "ktor" }
@@ -94,6 +96,11 @@ jackson-schema-jakarta = { module = "com.github.victools:jsonschema-module-jakar
 jakarta-validation = { module = "jakarta.validation:jakarta.validation-api", version.ref = "jakarta" }
 
 [bundles]
+ktor-client = [
+    "ktor-client",
+    "ktor-client-content-negotiation",
+    "ktor-client-serialization"
+]
 arrow = [
     "arrow-core",
     "arrow-fx-coroutines"

integrations/gcp/build.gradle.kts

@@ -1,51 +1,89 @@
 plugins {
-    id(libs.plugins.kotlin.multiplatform.get().pluginId)
-    id(libs.plugins.kotlinx.serialization.get().pluginId)
-    alias(libs.plugins.spotless)
-    alias(libs.plugins.arrow.gradle.publish)
-    alias(libs.plugins.semver.gradle)
+  id(libs.plugins.kotlin.multiplatform.get().pluginId)
+  id(libs.plugins.kotlinx.serialization.get().pluginId)
+  alias(libs.plugins.spotless)
+  alias(libs.plugins.arrow.gradle.publish)
+  alias(libs.plugins.semver.gradle)
 }
 
 repositories {
-    mavenCentral()
+  mavenCentral()
 }
 
 java {
-    sourceCompatibility = JavaVersion.VERSION_11
-    targetCompatibility = JavaVersion.VERSION_11
-    toolchain {
-        languageVersion = JavaLanguageVersion.of(11)
-    }
+  sourceCompatibility = JavaVersion.VERSION_11
+  targetCompatibility = JavaVersion.VERSION_11
+  toolchain {
+    languageVersion = JavaLanguageVersion.of(11)
+  }
 }
 
 kotlin {
-    jvm()
-    js(IR) {
-        browser()
-        nodejs()
+  jvm()
+  js(IR) {
+    browser()
+    nodejs()
+  }
+
+  linuxX64()
+  macosX64()
+  macosArm64()
+  mingwX64()
+
+  sourceSets {
+    val commonMain by getting {
+      dependencies {
+        api(projects.xefCore)
+        implementation(libs.bundles.ktor.client)
+      }
+    }
+
+    val jvmMain by getting {
+      dependencies {
+        implementation(libs.logback)
+        api(libs.ktor.client.cio)
+      }
+    }
+
+    val jsMain by getting {
+      dependencies {
+        api(libs.ktor.client.js)
+      }
     }
 
-    linuxX64()
-    macosX64()
-    macosArm64()
-    mingwX64()
-
-    sourceSets {
-        val commonMain by getting {
-            dependencies {
-                api(projects.xefCore)
-            }
-        }
+    val linuxX64Main by getting {
+      dependencies {
+        api(libs.ktor.client.cio)
+      }
     }
+
+    val macosX64Main by getting {
+      dependencies {
+        api(libs.ktor.client.cio)
+      }
+    }
+
+    val macosArm64Main by getting {
+      dependencies {
+        api(libs.ktor.client.cio)
+      }
+    }
+
+    val mingwX64Main by getting {
+      dependencies {
+        api(libs.ktor.client.winhttp)
+      }
+    }
+  }
 }
 
 spotless {
-    kotlin {
-        target("**/*.kt")
-        ktfmt().googleStyle()
-    }
+  kotlin {
+    target("**/*.kt")
+    ktfmt().googleStyle()
+  }
 }
 
 tasks.withType<AbstractPublishToMaven> {
-    dependsOn(tasks.withType<Sign>())
+  dependsOn(tasks.withType<Sign>())
 }

integrations/gcp/src/commonMain/kotlin/com/xebia/functional/xef/gcp/GcpClient.kt

@@ -0,0 +1,116 @@
+package com.xebia.functional.xef.gcp
+
+import com.xebia.functional.xef.AIError
+import io.ktor.client.HttpClient
+import io.ktor.client.call.body
+import io.ktor.client.plugins.HttpRequestRetry
+import io.ktor.client.plugins.HttpTimeout
+import io.ktor.client.plugins.contentnegotiation.ContentNegotiation
+import io.ktor.client.request.header
+import io.ktor.client.request.post
+import io.ktor.client.request.setBody
+import io.ktor.client.statement.bodyAsText
+import io.ktor.http.ContentType
+import io.ktor.http.HttpStatusCode
+import io.ktor.http.contentType
+import io.ktor.http.isSuccess
+import io.ktor.serialization.kotlinx.json.json
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.json.Json
+
+@OptIn(ExperimentalStdlibApi::class)
+class GcpClient(
+  private val apiEndpoint: String,
+  private val projectId: String,
+  private val modelId: String,
+  private val token: String
+) : AutoCloseable {
+  private val http: HttpClient = HttpClient {
+    install(HttpTimeout)
+    install(HttpRequestRetry)
+    install(ContentNegotiation) {
+      json(
+        Json {
+          encodeDefaults = false
+          isLenient = true
+        }
+      )
+    }
+  }
+
+  @Serializable
+  private data class Prompt(val instances: List<Instance>, val parameters: Parameters? = null)
+
+  @Serializable
+  private data class Instance(
+    val context: String? = null,
+    val examples: List<Example>? = null,
+    val messages: List<Message>,
+  )
+
+  @Serializable data class Example(val input: String, val output: String)
+
+  @Serializable private data class Message(val author: String, val content: String)
+
+  @Serializable
+  private class Parameters(
+    val temperature: Double? = null,
+    val maxOutputTokens: Int? = null,
+    val topK: Int? = null,
+    val topP: Double? = null
+  )
+
+  @Serializable data class Response(val predictions: List<Predictions>)
+
+  @Serializable
+  data class SafetyAttributes(
+    val blocked: Boolean,
+    val scores: List<String>,
+    val categories: List<String>
+  )
+
+  @Serializable data class CitationMetadata(val citations: List<String>)
+
+  @Serializable data class Candidates(val author: String?, val content: String?)
+
+  @Serializable
+  data class Predictions(
+    val safetyAttributes: List<SafetyAttributes>,
+    val citationMetadata: List<CitationMetadata>,
+    val candidates: List<Candidates>
+  )
+
+  suspend fun promptMessage(
+    prompt: String,
+    temperature: Double? = null,
+    maxOutputTokens: Int? = null,
+    topK: Int? = null,
+    topP: Double? = null
+  ): String {
+    val body =
+      Prompt(
+        listOf(Instance(messages = listOf(Message(author = "user", content = prompt)))),
+        Parameters(temperature, maxOutputTokens, topK, topP)
+      )
+    val response =
+      http.post(
+        "https://$apiEndpoint/v1/projects/$projectId/locations/us-central1/publishers/google/models/$modelId:predict"
+      ) {
+        header("Authorization", "Bearer $token")
+        contentType(ContentType.Application.Json)
+        setBody(body)
+      }
+
+    return if (response.status.isSuccess())
+      response.body<Response>().predictions.firstOrNull()?.candidates?.firstOrNull()?.content
+        ?: throw AIError.NoResponse()
+    else throw GcpClientException(response.status, response.bodyAsText())
+  }
+
+  class GcpClientException(val httpStatusCode: HttpStatusCode, val error: String) :
+    IllegalStateException("$httpStatusCode: $error")
+
+  override fun close() {
+    http.close()
+  }
+}