add post creating business case

business_cases/post_creating/server/build.gradle

@@ -0,0 +1,41 @@
+buildscript {
+    repositories {
+        mavenLocal()
+        jcenter()
+        mavenCentral()
+    }
+
+    dependencies {
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
+        classpath "com.jfrog.bintray.gradle:gradle-bintray-plugin:$gradle_bintray_plugin_version"
+    }
+}
+
+plugins {
+    id "org.jetbrains.kotlin.plugin.serialization" version "$kotlin_version"
+}
+
+project.version = "$core_version"
+project.group = "com.insanusmokrassar"
+
+apply plugin: "java-library"
+apply plugin: "kotlin"
+
+repositories {
+    mavenLocal()
+    jcenter()
+    mavenCentral()
+    maven { url "https://kotlin.bintray.com/kotlinx" }
+}
+
+dependencies {
+    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
+
+    api projectByName("business_cases.post_creating.common")
+    api projectByName("core.ktor.server")
+
+    testImplementation "org.xerial:sqlite-jdbc:$test_sqlite_version"
+    testImplementation "org.jetbrains.kotlin:kotlin-test"
+    testImplementation "org.jetbrains.kotlin:kotlin-test-junit"
+}

business_cases/post_creating/server/src/main/kotlin/com/insanusmokrassar/postssystem/business_cases/post_creating/server/PostCreatingRoutingCase.kt

@@ -0,0 +1,23 @@
+package com.insanusmokrassar.postssystem.business_cases.post_creating.server
+
+import com.insanusmokrassar.postssystem.core.post.RegisteredPost
+import com.insanusmokrassar.postssystem.ktor.server.unianswer
+import com.insanusmokrassar.postssystem.ktor.server.uniload
+import io.ktor.application.call
+import io.ktor.routing.*
+import kotlinx.serialization.builtins.nullable
+
+fun Route.configurePostCreatingRoutes(
+    origin: PostCreatingCase
+) {
+    route(postCreatingRootRoute) {
+        post(postCreatingCreatePostRoute) {
+            val model = call.uniload(PostCreatingCreatePostModel.serializer())
+
+            call.unianswer(
+                RegisteredPost.serializer().nullable,
+                origin.createPost(model.postContent, model.triggerId)
+            )
+        }
+    }
+}