Add composer api

src/main/kotlin/org/exploit/keeper/controller/external/ComposeController.kt

@@ -0,0 +1,30 @@
+package org.exploit.keeper.controller.external
+
+import com.linecorp.armeria.server.ServerBuilder
+import jakarta.inject.Singleton
+import org.exploit.keeper.constant.common.ErrorType
+import org.exploit.keeper.constant.permission.Permission
+import org.exploit.keeper.controller.support.ControllerSupport
+import org.exploit.keeper.exception.TKeeperException
+import org.exploit.keeper.model.api.incoming.Sign
+import org.exploit.keeper.service.compose.KeeperComposer
+import org.exploit.keeper.util.extension.http.hasPermission
+import org.exploit.keeper.util.validation.InputValidator
+
+@Singleton
+class ComposeController(
+    private val composer: KeeperComposer,
+    private val support: ControllerSupport
+): ExternalController {
+    override fun register(sb: ServerBuilder) = with(support) {
+        sb.publicPost("/v2/keeper/compose", Sign::class.java) { ctx, body ->
+            if (!ctx.hasPermission(Permission.keySign(body.keyId)))
+                throw TKeeperException(ErrorType.ACCESS_DENIED)
+
+            if (!InputValidator.isValidKeyId(body.keyId))
+                throw TKeeperException(ErrorType.INVALID_KEY_ID)
+
+            composer.compose(body)
+        }
+    }
+}

src/main/kotlin/org/exploit/keeper/model/api/outgoing/CalculatedSignature.kt

@@ -1,10 +1,11 @@
 package org.exploit.keeper.model.api.outgoing
 
 import org.exploit.keeper.model.capability.HasImposters
+import org.exploit.keeper.model.outcome.Outcome
 
 data class CalculatedSignature(
     val type: String,
     val signature64: String? = null,
     val generation: Int,
     override val imposters: List<String>,
-): HasImposters
+): HasImposters, Outcome

src/main/kotlin/org/exploit/keeper/model/outcome/Outcome.kt

@@ -0,0 +1,3 @@
+package org.exploit.keeper.model.outcome
+
+interface Outcome

src/main/kotlin/org/exploit/keeper/service/compose/KeeperComposer.kt

@@ -0,0 +1,23 @@
+package org.exploit.keeper.service.compose
+
+import jakarta.inject.Singleton
+import org.exploit.keeper.model.api.incoming.Sign
+import org.exploit.keeper.model.outcome.Outcome
+import org.exploit.keeper.service.compose.spi.Composer
+import org.exploit.keeper.service.signature.registry.SigningSessionManager
+import org.exploit.keeper.util.extension.equalsIgnoreCase
+
+@Singleton
+class KeeperComposer(private val manager: SigningSessionManager, private val composers: List<Composer>) {
+    fun compose(body: Sign): Outcome {
+        val signature = manager.coordinate(body)
+
+        val command = body.command
+
+        val composer = composers.find {
+            it.type.equalsIgnoreCase(body.command.type)
+        } ?: return signature
+
+        return composer.compose(command, signature)
+    }
+}

src/main/kotlin/org/exploit/keeper/service/compose/spi/Composer.kt

@@ -0,0 +1,11 @@
+package org.exploit.keeper.service.compose.spi
+
+import org.exploit.keeper.model.api.outgoing.CalculatedSignature
+import org.exploit.keeper.model.command.Command
+import org.exploit.keeper.model.outcome.Outcome
+
+interface Composer {
+    val type: String
+
+    fun compose(command: Command, signature: CalculatedSignature): Outcome
+}