HONEYCOMB-358 - Activation module

Provides module that provides set of distribution started modules

Change-Id: I54287cc17f3af7d51a47a7342e5b8496e5ade00e
Signed-off-by: Jan Srnicek <jsrnicek@cisco.com>

7 files changed, 159 insertions, 31 deletions

diff --git a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/Main.java b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/Main.java
index 4769b570d..265740bcc 100644
--- a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/Main.java
+++ b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/Main.java
@@ -16,11 +16,10 @@
 
 package io.fd.honeycomb.infra.distro;
 
-import static io.fd.honeycomb.infra.distro.ActiveModuleProvider.STANDARD_MODULES_RELATIVE_PATH;
-import static io.fd.honeycomb.infra.distro.ActiveModuleProvider.aggregateResources;
-import static io.fd.honeycomb.infra.distro.ActiveModuleProvider.loadActiveModules;
+import static com.google.inject.Guice.createInjector;
 
 import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableSet;
 import com.google.inject.ConfigurationException;
 import com.google.inject.CreationException;
 import com.google.inject.Guice;
@@ -31,6 +30,8 @@ import com.google.inject.ProvisionException;
 import com.google.inject.name.Names;
 import io.fd.honeycomb.data.init.DataTreeInitializer;
 import io.fd.honeycomb.data.init.InitializerRegistry;
+import io.fd.honeycomb.infra.distro.activation.ActivationModule;
+import io.fd.honeycomb.infra.distro.activation.ActiveModules;
 import io.fd.honeycomb.infra.distro.cfgattrs.HoneycombConfiguration;
 import io.fd.honeycomb.infra.distro.initializer.InitializerPipelineModule;
 import io.fd.honeycomb.infra.distro.netconf.HoneycombNotification2NetconfProvider;
@@ -38,7 +39,6 @@ import io.fd.honeycomb.infra.distro.netconf.NetconfModule;
 import io.fd.honeycomb.infra.distro.netconf.NetconfSshServerProvider;
 import io.fd.honeycomb.infra.distro.netconf.NetconfTcpServerProvider;
 import io.fd.honeycomb.infra.distro.restconf.RestconfModule;
-import java.util.Set;
 import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.server.ServerConnector;
 import org.opendaylight.netconf.mapping.api.NetconfOperationServiceFactory;
@@ -54,17 +54,23 @@ public final class Main {
     }
 
     public static void main(String[] args) {
-        final ClassLoader classLoader = Main.class.getClassLoader();
-        init(loadActiveModules(aggregateResources(STANDARD_MODULES_RELATIVE_PATH, classLoader)));
+        init();
     }
 
     /**
      * Initialize the Honeycomb with provided modules
      */
-    public static Injector init(final Set<? extends Module> modules) {
+    public static Injector init() {
         try {
             LOG.info("Starting honeycomb");
-            Injector injector = Guice.createInjector(modules);
+            final ActivationModule activationModule = new ActivationModule();
+            // creating child injector does not work in this case, so just create injector, and does not store ref
+            // to it, or its active modules instance
+            Injector injector = createInjector(ImmutableSet.<Module>builder()
+                    .add(activationModule)
+                    .addAll(createInjector(activationModule).getInstance(ActiveModules.class).createModuleInstances())
+                    .build());
+
             LOG.info("Honeycomb configuration: {}", injector.getInstance(HoneycombConfiguration.class));
 
             // Log all bindings
diff --git a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActivationConfig.java b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActivationConfig.java
new file mode 100644
index 000000000..8777c32a2
--- /dev/null
+++ b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActivationConfig.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2016 Cisco 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.fd.honeycomb.infra.distro.activation;
+
+import java.util.Optional;
+import net.jmob.guice.conf.core.BindConfig;
+import net.jmob.guice.conf.core.InjectConfig;
+import net.jmob.guice.conf.core.Syntax;
+
+@BindConfig(value = "activation", syntax = Syntax.JSON)
+public class ActivationConfig {
+
+    @InjectConfig("modules-resource-path")
+    private String modulesResourcePath;
+
+    public String getModulesResourcePath() {
+        return Optional.ofNullable(modulesResourcePath).orElse("../modules/");
+    }
+}
diff --git a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActivationModule.java b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActivationModule.java
new file mode 100644
index 000000000..00f77a66d
--- /dev/null
+++ b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActivationModule.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2016 Cisco 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.fd.honeycomb.infra.distro.activation;
+
+import com.google.inject.AbstractModule;
+import net.jmob.guice.conf.core.ConfigurationModule;
+
+/**
+ * Module that provides set of modules activated by distribution and binds this set to be available
+ */
+public class ActivationModule extends AbstractModule {
+    @Override
+    protected void configure() {
+        install(ConfigurationModule.create());
+        requestInjection(ActivationConfig.class);
+        bind(ActiveModules.class).toProvider(ActiveModuleProvider.class).asEagerSingleton();
+    }
+}
diff --git a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/ActiveModuleProvider.java b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActiveModuleProvider.java
index 03c56969d..21d108082 100644
--- a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/ActiveModuleProvider.java
+++ b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActiveModuleProvider.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Copyright (c) 2017 Cisco 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.
@@ -14,10 +14,12 @@
  * limitations under the License.
  */
 
-package io.fd.honeycomb.infra.distro;
+package io.fd.honeycomb.infra.distro.activation;
 
 import com.google.common.collect.ImmutableList;
+import com.google.inject.Inject;
 import com.google.inject.Module;
+import com.google.inject.Provider;
 import java.io.File;
 import java.io.IOException;
 import java.net.URI;
@@ -38,15 +40,23 @@ import org.slf4j.LoggerFactory;
 /**
  * Provides list of active modules for distribution
  */
-public class ActiveModuleProvider {
+class ActiveModuleProvider implements Provider<ActiveModules> {
 
-    public static final String STANDARD_MODULES_RELATIVE_PATH = "../modules/";
     private static final Logger LOG = LoggerFactory.getLogger(ActiveModuleProvider.class);
 
+    @Inject
+    private ActivationConfig config;
+
+    @Override
+    public ActiveModules get() {
+        return new ActiveModules(loadActiveModules(
+                aggregateResources(config.getModulesResourcePath(), Thread.currentThread().getContextClassLoader())));
+    }
+
     /**
      * Provide unique set of active modules filtered from provided resources
      */
-    public static Set<Module> loadActiveModules(@Nonnull final List<String> moduleNames) {
+    static Set<Class<? extends Module>> loadActiveModules(@Nonnull final List<String> moduleNames) {
         final ClassLoader classLoader = ActiveModuleProvider.class.getClassLoader();
         LOG.info("Reading active modules configuration for distribution");
 
@@ -58,10 +68,9 @@ public class ActiveModuleProvider {
                 .filter(nonEmptyLine -> !nonEmptyLine.startsWith("//"))
                 // filter duplicates
                 .distinct()
-                .map(validLine -> nameToClass(validLine, classLoader))
+                .map(validLine -> moduleNameToClass(validLine, classLoader))
                 // filters out classes that are not modules
                 .filter(ActiveModuleProvider::filterNonModules)
-                .map(ActiveModuleProvider::classToInstance)
                 .collect(Collectors.toSet());
     }
 
@@ -127,28 +136,15 @@ public class ActiveModuleProvider {
     /**
      * Loads class by provided name
      */
-    private static Class<?> nameToClass(final String name,
-                                        final ClassLoader classLoader) {
+    private static Class<? extends Module> moduleNameToClass(final String name,
+                                                             final ClassLoader classLoader) {
         try {
             LOG.info("Loading module class {}", name);
-            return classLoader.loadClass(name);
+            return (Class<? extends Module>) classLoader.loadClass(name);
         } catch (ClassNotFoundException e) {
             LOG.error("Unable to convert {} to class, make sure you've provided sources to classpath", name);
             throw new IllegalStateException(
                     "Unable to convert " + name + " to class, make sure you've provided sources to classpath", e);
         }
     }
-
-    /**
-     * Creates instance of module class
-     */
-    private static Module classToInstance(final Class<?> moduleClass) {
-        try {
-            LOG.info("Creating instance for module {}", moduleClass);
-            return Module.class.cast(moduleClass.newInstance());
-        } catch (InstantiationException | IllegalAccessException e) {
-            LOG.error("Unable to create instance for class {}", moduleClass, e);
-            throw new IllegalStateException("Unable to create instance for class" + moduleClass, e);
-        }
-    }
 }
diff --git a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActiveModules.java b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActiveModules.java
new file mode 100644
index 000000000..f729f00b9
--- /dev/null
+++ b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/activation/ActiveModules.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2016 Cisco 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.fd.honeycomb.infra.distro.activation;
+
+import static java.lang.String.format;
+
+import com.google.inject.Module;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * Provides static set of active activeModulesClasses
+ */
+public class ActiveModules {
+    private final Set<Class<? extends Module>> activeModulesClasses;
+
+    public ActiveModules(final Set<Class<? extends Module>> activeModulesClasses) {
+        this.activeModulesClasses = activeModulesClasses;
+    }
+
+    public Set<Class<? extends Module>> getActiveModulesClasses() {
+        return activeModulesClasses;
+    }
+
+    public Set<? extends Module> createModuleInstances() {
+        return activeModulesClasses.stream()
+                .map(moduleClass -> {
+                    try {
+                        return moduleClass.newInstance();
+                    } catch (InstantiationException | IllegalAccessException e) {
+                        throw new IllegalStateException(format("Unable to create instance of module %s", moduleClass),
+                                e);
+                    }
+                }).collect(Collectors.toSet());
+    }
+
+    @Override
+    public String toString() {
+        return "ActiveModules{" +
+                "activeModulesClasses=" + activeModulesClasses +
+                '}';
+    }
+}
diff --git a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/schema/YangBindingProviderModule.java b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/schema/YangBindingProviderModule.java
index 4348333a9..8e402808b 100644
--- a/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/schema/YangBindingProviderModule.java
+++ b/infra/minimal-distribution/src/main/java/io/fd/honeycomb/infra/distro/schema/YangBindingProviderModule.java
@@ -56,6 +56,7 @@ public class YangBindingProviderModule extends AbstractModule {
                 .map(YangBindingProviderModule::urlToString)
                 .flatMap(content -> Lists.newArrayList(content.split("\n")).stream())
                 .filter(line -> !Strings.isNullOrEmpty(line.trim()))
+                .distinct()
                 .map(YangBindingProviderModule::loadClass)
                 .forEach(providerClass -> {
                     LOG.debug("ModuleProvider found for {}", providerClass);
diff --git a/infra/minimal-distribution/src/main/resources/honeycomb-minimal-resources/config/activation.json b/infra/minimal-distribution/src/main/resources/honeycomb-minimal-resources/config/activation.json
new file mode 100644
index 000000000..7b6f44a20
--- /dev/null
+++ b/infra/minimal-distribution/src/main/resources/honeycomb-minimal-resources/config/activation.json
@@ -0,0 +1,3 @@
+{
+  "modules-resource-path": "../modules/"
+}
\ No newline at end of file