[a2a] Add CORS configuration

Author: EugeneTheDev

a2a/a2a-transport/a2a-transport-server-jsonrpc-http/build.gradle.kts

@@ -19,6 +19,7 @@ kotlin {
                 implementation(libs.ktor.serialization.kotlinx.json)
                 implementation(libs.ktor.server.content.negotiation)
                 implementation(libs.ktor.server.sse)
+                implementation(libs.ktor.server.cors)
             }
         }
 

a2a/a2a-transport/a2a-transport-server-jsonrpc-http/src/commonMain/kotlin/ai/koog/a2a/transport/server/jsonrpc/http/HttpJSONRPCServerTransport.kt

@@ -19,6 +19,7 @@ import io.ktor.server.engine.ApplicationEngineFactory
 import io.ktor.server.engine.EmbeddedServer
 import io.ktor.server.engine.embeddedServer
 import io.ktor.server.plugins.contentnegotiation.ContentNegotiation
+import io.ktor.server.plugins.cors.routing.CORS
 import io.ktor.server.request.receiveText
 import io.ktor.server.response.header
 import io.ktor.server.response.respond
@@ -130,6 +131,11 @@ public class HttpJSONRPCServerTransport(
                     json(JSONRPCJson)
                 }
 
+                install(CORS) {
+                    anyHost()
+                    allowNonSimpleContentTypes = true
+                }
+
                 transportRoutes(this, path)
 
                 if (agentCard != null) {

gradle/libs.versions.toml

@@ -71,6 +71,7 @@ ktor-server-cio = { module = "io.ktor:ktor-server-cio", version.ref = "ktor3" }
 ktor-server-netty = { module = "io.ktor:ktor-server-netty-jvm", version.ref = "ktor3" }
 ktor-server-sse = { module = "io.ktor:ktor-server-sse", version.ref = "ktor3" }
 ktor-server-content-negotiation = { module = "io.ktor:ktor-server-content-negotiation", version.ref = "ktor3" }
+ktor-server-cors = { module = "io.ktor:ktor-server-cors", version.ref = "ktor3" }
 ktor-server-test-host = { module = "io.ktor:ktor-server-test-host", version.ref = "ktor3" }
 lettuce-core = { module = "io.lettuce:lettuce-core", version.ref = "lettuce" }
 logback-classic = { module = "ch.qos.logback:logback-classic", version.ref = "logback" }