lifecycle: Introduce a LifecycleConfig. See killbill/killbill#1911

We have a first use case to configure our lifecycle to decide whether system should exit
when some plugins fail to start.

lifecycle/pom.xml

@@ -59,6 +59,10 @@
             <groupId>org.kill-bill.billing</groupId>
             <artifactId>killbill-platform-api</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.kill-bill.billing</groupId>
+            <artifactId>killbill-platform-base</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.kill-bill.commons</groupId>
             <artifactId>killbill-clock</artifactId>

lifecycle/src/main/java/org/killbill/billing/lifecycle/DefaultLifecycle.java

@@ -35,6 +35,7 @@
 import javax.inject.Inject;
 
 import org.killbill.billing.lifecycle.api.Lifecycle;
+import org.killbill.billing.lifecycle.config.LifecycleConfig;
 import org.killbill.billing.platform.api.KillbillService;
 import org.killbill.billing.platform.api.LifecycleHandlerType;
 import org.killbill.billing.platform.api.LifecycleHandlerType.LifecycleLevel;
@@ -52,26 +53,25 @@ public class DefaultLifecycle implements Lifecycle {
     // See https://github.com/killbill/killbill-commons/issues/143
     private final Map<LifecycleLevel, SortedSet<LifecycleHandler<? extends KillbillService>>> handlersByLevel;
 
-    private static final String EXIT_ON_LIFECYCLE_ERROR_PROPERTY = "org.killbill.server.exit.on.lifecycle.error";
-    private boolean exitOnError;
+    private final LifecycleConfig config;
 
     @Inject
-    public DefaultLifecycle(final Injector injector) {
-        this();
+    public DefaultLifecycle(final Injector injector, final LifecycleConfig config) {
+        this(config);
         final ServiceFinder<KillbillService> serviceFinder = new ServiceFinder<>(DefaultLifecycle.class.getClassLoader(), KillbillService.class.getName());
-        exitOnError = System.getProperty(EXIT_ON_LIFECYCLE_ERROR_PROPERTY) != null && Boolean.parseBoolean(System.getProperty(EXIT_ON_LIFECYCLE_ERROR_PROPERTY));
         init(serviceFinder, injector);
     }
 
     // For testing
     public DefaultLifecycle(final Iterable<? extends KillbillService> services) {
-        this();
+        this((LifecycleConfig) null);
         init(services);
     }
 
 
-    private DefaultLifecycle() {
+    private DefaultLifecycle(final LifecycleConfig config) {
         this.handlersByLevel = new ConcurrentHashMap<>();
+        this.config = config;
     }
 
     @Override
@@ -158,8 +158,8 @@ private void doFireStage(final LifecycleHandlerType.LifecycleLevel level) {
                 method.invoke(target);
             } catch (final Exception e) {
                 logWarn("Killbill lifecycle failed to invoke lifecycle handler", e);
-                if (exitOnError) {
-                    log.info("{} is set, so exiting..", EXIT_ON_LIFECYCLE_ERROR_PROPERTY);
+                if (config.isServerExitOnLifecycleError()) {
+                    log.warn("Existing as system was configured to exist on lifecycle error ");
                     System.exit(1);
                 }
             }

lifecycle/src/main/java/org/killbill/billing/lifecycle/config/LifecycleConfig.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2020-2023 Equinix, Inc
+ * Copyright 2014-2023 The Billing Project, LLC
+ *
+ * The Billing Project licenses this file to you 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 org.killbill.billing.lifecycle.config;
+
+import org.killbill.billing.platform.api.KillbillPlatformConfig;
+import org.skife.config.Config;
+import org.skife.config.Default;
+import org.skife.config.Description;
+
+public interface LifecycleConfig extends KillbillPlatformConfig {
+
+    @Config(KILL_BILL_NAMESPACE + "server.exit.on.lifecycle.error")
+    @Default("false")
+    @Description("Exit on lifecycle error")
+    public boolean isServerExitOnLifecycleError();
+
+}

lifecycle/src/main/java/org/killbill/billing/lifecycle/glue/LifecycleModule.java

@@ -21,17 +21,32 @@
 
 import org.killbill.billing.lifecycle.DefaultLifecycle;
 import org.killbill.billing.lifecycle.api.Lifecycle;
+import org.killbill.billing.lifecycle.config.LifecycleConfig;
+import org.killbill.billing.platform.api.KillbillConfigSource;
+import org.killbill.billing.platform.glue.KillBillPlatformModuleBase;
+import org.skife.config.ConfigSource;
+import org.skife.config.ConfigurationObjectFactory;
 
 import com.google.inject.AbstractModule;
 
-public class LifecycleModule extends AbstractModule {
+public class LifecycleModule extends KillBillPlatformModuleBase {
+
+    public LifecycleModule(final KillbillConfigSource configSource) {
+        super(configSource);
+    }
 
     @Override
     protected void configure() {
         installLifecycle();
     }
 
+    protected void configureConfig() {
+        final LifecycleConfig lifecycleConfig = new ConfigurationObjectFactory(skifeConfigSource).build(LifecycleConfig.class);
+        bind(LifecycleConfig.class).toInstance(lifecycleConfig);
+    }
+
     protected void installLifecycle() {
+        configureConfig();
         bind(Lifecycle.class).to(DefaultLifecycle.class).asEagerSingleton();
     }
 }

lifecycle/src/test/java/org/killbill/billing/lifecycle/TestLifecycle.java

@@ -224,7 +224,7 @@ public static class LifecycleNoWarn extends DefaultLifecycle {
 
         @Inject
         public LifecycleNoWarn(final Injector injector) {
-            super(injector);
+            super(injector, null);
         }
 
         @Override

server/src/main/java/org/killbill/billing/server/modules/KillbillPlatformModule.java

@@ -204,7 +204,7 @@ protected void configureEmbeddedDBs() {
     }
 
     protected void configureLifecycle() {
-        install(new LifecycleModule());
+        install(new LifecycleModule(configSource));
     }
 
     protected void configureBuses() {