add kontor-javalin

kontor-javalin/api/build.gradle

@@ -0,0 +1,17 @@
+plugins {
+    id 'application'
+}
+
+dependencies {
+    implementation project(":models")     // We need this dependency for serializing persons to JSON
+    implementation project(":services")   // We'll make use of the InMemoryPersonReader soon
+    
+    implementation libs.javalin   // Pulling in Javalin
+    implementation libs.jackson   // For JSON serialization of persons 
+    implementation libs.slf4j     // To see some Javalin logging
+}
+
+application {
+    mainClass = "de.thpeetz.kontor.api.Main"
+    mainModule = "de.thpeetz.kontor.api"
+}

kontor-javalin/api/src/main/java/de/thpeetz/kontor/api/Main.java

@@ -0,0 +1,30 @@
+package de.thpeetz.kontor.api;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.javalin.Javalin;
+import de.thpeetz.kontor.services.api.PersonReader;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.ServiceLoader;
+
+public class Main {
+    private static Logger logger = LoggerFactory.getLogger(Main.class);
+    private static short port = 7312;
+
+    public static void main(String[] args) {
+        var personReader = ServiceLoader.load(PersonReader.class).findFirst().get(); // <-- Getting an implementation
+                                                                                     // for the PersonReader interface
+                                                                                     // from the ServiceLoader
+        var objMapper = new ObjectMapper();
+        var result = objMapper.valueToTree(personReader.getAll());
+
+        logger.info("API: found {} people.", personReader.getAll().size());
+
+        var app = Javalin.create().start(port);
+        app.get("/ping", ctx -> ctx.result("pong"));
+        app.get("/persons", ctx -> ctx.json(result));
+
+        logger.info("API's alive for real :-)))");
+    }
+}

kontor-javalin/api/src/main/java/module-info.java

@@ -0,0 +1,10 @@
+module de.thpeetz.kontor.api {
+    requires io.javalin;
+    requires com.fasterxml.jackson.databind;
+    requires org.slf4j;
+    requires kotlin.stdlib;
+
+    requires de.thpeetz.kontor.services;
+
+    uses de.thpeetz.kontor.services.api.PersonReader; 
+}