4.x: Helidon main class

applications/mp/pom.xml

@@ -36,7 +36,7 @@
         <version.plugin.jaxb2>0.14.0</version.plugin.jaxb2>
         <version.plugin.eclipselink>2.7.5.1</version.plugin.eclipselink>
         <version.plugin.hibernate.enhance>6.1.7.Final</version.plugin.hibernate.enhance>
-        <mainClass>io.helidon.microprofile.cdi.Main</mainClass>
+        <mainClass>io.helidon.Main</mainClass>
     </properties>
 
     <build>

bom/pom.xml

@@ -37,6 +37,11 @@
 
     <dependencyManagement>
         <dependencies>
+            <dependency>
+                <groupId>io.helidon</groupId>
+                <artifactId>helidon</artifactId>
+                <version>${helidon.version}</version>
+            </dependency>
             <!-- webserver -->
             <dependency>
                 <groupId>io.helidon.reactive.webserver</groupId>
@@ -1175,11 +1180,6 @@
             </dependency>
 
             <!-- Níma -->
-            <dependency>
-                <groupId>io.helidon.nima</groupId>
-                <artifactId>helidon-nima</artifactId>
-                <version>${helidon.version}</version>
-            </dependency>
             <dependency>
                 <groupId>io.helidon.nima.common</groupId>
                 <artifactId>helidon-nima-common-tls</artifactId>

config/config/src/main/java/io/helidon/config/ConfigMappers.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2022 Oracle and/or its affiliates.
+ * Copyright (c) 2017, 2023 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -81,6 +81,7 @@ private ConfigMappers() {
     private static Map<Class<?>, Function<Config, ?>> initEssentialMappers() {
 
         return Map.of(Config.class, (node) -> node,
+                      io.helidon.common.config.Config.class, (node) -> node,
                       String.class, wrap(value -> value),
                       OptionalInt.class, ConfigMappers::optionalIntEssential,
                       OptionalLong.class, ConfigMappers::optionalLongEssential,

examples/nima/fault-tolerance/pom.xml

@@ -30,13 +30,13 @@
     <name>Helidon Examples Níma Fault Tolerance</name>
 
     <properties>
-        <mainClass>io.helidon.examples.nima.faulttolerance.FtMain</mainClass>
+        <mainClass>io.helidon.Main</mainClass>
     </properties>
 
     <dependencies>
         <dependency>
-            <groupId>io.helidon.nima</groupId>
-            <artifactId>helidon-nima</artifactId>
+            <groupId>io.helidon</groupId>
+            <artifactId>helidon</artifactId>
         </dependency>
         <dependency>
             <groupId>io.helidon.nima.webserver</groupId>

examples/nima/fault-tolerance/src/main/java/io/helidon/examples/nima/faulttolerance/GreetEndpoint.java

@@ -55,7 +55,6 @@ String greet() {
     String greetNamed(@Endpoint.PathParam("name") String name,
                       @Endpoint.QueryParam(value = "throw", defaultValue = "false") String shouldThrow,
                       @Endpoint.HeaderParam(Http.Header.HOST_STRING) String hostHeader) {
-        System.out.println(Thread.currentThread().getName());
         if ("true".equalsIgnoreCase(shouldThrow)) {
             throw new PicoException("Failed on purpose");
         }

examples/nima/fault-tolerance/src/main/resources/application.yaml

@@ -26,4 +26,6 @@ fault-tolerance:
     myname:
       executor-name: "platform-executor"
     other-name:
-      executor-name: "abcd"
+      executor-name: "abcd"
+pico:
+  permits-dynamic: true

examples/nima/fault-tolerance/src/test/java/io/helidon/examples/nima/faulttolerance/FaultToleranceTest.java

@@ -16,6 +16,7 @@
 
 package io.helidon.examples.nima.faulttolerance;
 
+import io.helidon.Main;
 import io.helidon.common.http.Http;
 import io.helidon.nima.webclient.WebClient;
 import io.helidon.nima.webclient.http1.Http1Client;
@@ -39,7 +40,7 @@ class FaultToleranceTest {
 
     @BeforeAll
     static void init() {
-        FtMain.main(new String[0]);
+        Main.main(new String[0]);
         WebServer webServer = PicoServices.realizedServices()
                 .lookup(WebServer.class)
                 .get();
@@ -59,8 +60,8 @@ static void init() {
 
     @AfterAll
     static void shutDown() {
-        //        PicoServices.picoServices()
-        //                .map(PicoServices::shutdown);
+        PicoServices.picoServices()
+                .map(PicoServices::shutdown);
     }
 
     @Test
@@ -95,7 +96,6 @@ void testGreetNamed() {
     }
 
     @Test
-    @Disabled
     void testGreetNamedFallback() {
         String response = webClient.get("/greet/helidon")
                 .queryParam("throw", "true")

examples/nima/imperative/pom.xml

@@ -35,26 +35,10 @@
     </properties>
 
     <dependencies>
-        <dependency>
-            <groupId>io.helidon.nima</groupId>
-            <artifactId>helidon-nima</artifactId>
-        </dependency>
         <dependency>
             <groupId>io.helidon.nima.webserver</groupId>
             <artifactId>helidon-nima-webserver</artifactId>
         </dependency>
-        <dependency>
-            <groupId>io.helidon.pico</groupId>
-            <artifactId>helidon-pico-api</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>io.helidon.pico</groupId>
-            <artifactId>helidon-pico-runtime</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>io.helidon.pico.configdriven</groupId>
-            <artifactId>helidon-pico-configdriven-runtime</artifactId>
-        </dependency>
         <dependency>
             <groupId>io.helidon.config</groupId>
             <artifactId>helidon-config-yaml</artifactId>

examples/nima/imperative/src/main/java/io/helidon/examples/nima/imperative/ImperativeMain.java

@@ -17,8 +17,8 @@
 package io.helidon.examples.nima.imperative;
 
 import io.helidon.common.config.Config;
+import io.helidon.common.config.GlobalConfig;
 import io.helidon.common.http.Http;
-import io.helidon.nima.Nima;
 import io.helidon.nima.webserver.WebServer;
 import io.helidon.nima.webserver.http.HttpRouting;
 
@@ -35,7 +35,7 @@ private ImperativeMain() {
      * @param args ignored
      */
     public static void main(String[] args) {
-        Config config = Nima.config();
+        Config config = GlobalConfig.config();
 
         WebServer server = WebServer.create(ws -> ws.config(config.get("server"))
                         .routing(ImperativeMain::routing))

nima/nima/pom.xml → helidon/pom.xml

@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
-
-    Copyright (c) 2022, 2023 Oracle and/or its affiliates.
+    Copyright (c) 2023 Oracle and/or its affiliates.
 
     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
@@ -14,32 +13,31 @@
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
+  -->
 
--->
-
-<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-        xmlns="http://maven.apache.org/POM/4.0.0"
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
-
     <parent>
-        <groupId>io.helidon.nima</groupId>
-        <artifactId>helidon-nima-project</artifactId>
+        <groupId>io.helidon</groupId>
+        <artifactId>helidon-project</artifactId>
         <version>4.0.0-SNAPSHOT</version>
-        <relativePath>../pom.xml</relativePath>
     </parent>
 
-    <artifactId>helidon-nima</artifactId>
-    <name>Helidon Níma</name>
+    <artifactId>helidon</artifactId>
+    <name>Helidon</name>
+
+    <description>Helidon main entry point</description>
 
     <dependencies>
         <dependency>
             <groupId>io.helidon.common</groupId>
             <artifactId>helidon-common</artifactId>
         </dependency>
         <dependency>
-            <groupId>io.helidon.config</groupId>
-            <artifactId>helidon-config</artifactId>
+            <groupId>io.helidon.logging</groupId>
+            <artifactId>helidon-logging-common</artifactId>
         </dependency>
     </dependencies>
 </project>

helidon/src/main/java/io/helidon/Main.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2023 Oracle and/or its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.helidon;
+
+import java.util.ServiceLoader;
+
+import io.helidon.common.HelidonServiceLoader;
+import io.helidon.logging.common.LogConfig;
+import io.helidon.spi.HelidonStartupProvider;
+
+/**
+ * Main entry point for any Helidon application.
+ * {@link java.util.ServiceLoader} is used to discover the correct {@link io.helidon.spi.HelidonStartupProvider}
+ * to start the application (probably either Helidon Injection based application, or a CDI based application).
+ * <p>
+ * The default option is to start Helidon injection based application.
+ */
+public class Main {
+    static {
+        LogConfig.initClass();
+    }
+
+    private Main() {
+    }
+
+    /**
+     * Start Helidon.
+     * This method is required to start directly from a command line.
+     *
+     * @param args arguments of the application
+     */
+    public static void main(String[] args) {
+        // we always initialize logging
+        LogConfig.configureRuntime();
+
+        // this should only be called once in a lifetime of the server, so no need to optimize
+        var services = HelidonServiceLoader.create(ServiceLoader.load(HelidonStartupProvider.class))
+                .asList();
+
+        if (services.isEmpty()) {
+            throw new IllegalStateException("Helidon Main class can only be called if a startup provider is available. "
+                                                    + "Please use either Helidon Injection, or Helidon MicroProfile "
+                                                    + "(or a custom extension). If neither is available, you should use "
+                                                    + "your own Main class.");
+        }
+        services.get(0).start(args);
+    }
+}

nima/nima/src/main/java/module-info.java → helidon/src/main/java/io/helidon/package-info.java

@@ -13,10 +13,10 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-module io.helidon.nima {
-    requires io.helidon.common;
-    requires io.helidon.config;
-    requires io.helidon.logging.common;
 
-    exports io.helidon.nima;
-}
+/**
+ * Startup of Helidon applications.
+ *
+ * @see io.helidon.Main
+ */
+package io.helidon;

examples/nima/fault-tolerance/src/main/java/io/helidon/examples/nima/faulttolerance/ConfigService.java → helidon/src/main/java/io/helidon/spi/HelidonStartupProvider.java

@@ -14,26 +14,17 @@
  * limitations under the License.
  */
 
-package io.helidon.examples.nima.faulttolerance;
-
-import io.helidon.config.Config;
-
-import jakarta.inject.Provider;
-import jakarta.inject.Singleton;
+package io.helidon.spi;
 
 /**
- * This service will be part of Níma on Pico module.
- * It may use pico to get config sources exposed through pico.
+ * {@link java.util.ServiceLoader} provider interface to discover the correct startup type.
+ * Only the first provider (with the highest {@link io.helidon.common.Weight}) will be used.
  */
-@Singleton
-class ConfigService implements Provider<Config> {
-    private static volatile Config config;
-    static void config(Config config) {
-        ConfigService.config = config;
-    }
-
-    @Override
-    public Config get() {
-        return config;
-    }
+public interface HelidonStartupProvider {
+    /**
+     * Start the runtime.
+     *
+     * @param arguments command line arguments
+     */
+    void start(String[] arguments);
 }