Add plugins registration result handling

Plugins now receive registration results via onPluginsReady, and PluginMetadata requires a version.
Creates RegistrationCompleteResult to track plugin registration success or failure.
Updates tests and interfaces to support these changes.

Author: agrognetti

launchdarkly-android-client-sdk/src/androidTest/java/com/launchdarkly/sdk/android/LDClientPluginsTest.java

@@ -151,7 +151,13 @@ public PluginMetadata getMetadata() {
                 @NonNull
                 @Override
                 public String getName() {
-                    return "mock-plugin";
+                    return "mock-plugin-name";
+                }
+
+                @NonNull
+                @Override
+                public String getVersion() {
+                    return "mock-plugin-version";
                 }
             };
         }

launchdarkly-android-client-sdk/src/main/java/com/launchdarkly/sdk/android/LDClient.java

@@ -11,21 +11,23 @@
 import com.launchdarkly.sdk.EvaluationReason;
 import com.launchdarkly.sdk.LDContext;
 import com.launchdarkly.sdk.LDValue;
+import com.launchdarkly.sdk.android.DataModel.Flag;
 import com.launchdarkly.sdk.android.env.EnvironmentReporterBuilder;
 import com.launchdarkly.sdk.android.env.IEnvironmentReporter;
 import com.launchdarkly.sdk.android.integrations.EnvironmentMetadata;
 import com.launchdarkly.sdk.android.integrations.Hook;
 import com.launchdarkly.sdk.android.integrations.IdentifySeriesResult;
 import com.launchdarkly.sdk.android.integrations.Plugin;
+import com.launchdarkly.sdk.android.integrations.RegistrationCompleteResult;
 import com.launchdarkly.sdk.android.integrations.SdkMetadata;
 import com.launchdarkly.sdk.android.subsystems.ApplicationInfo;
 import com.launchdarkly.sdk.android.subsystems.Callback;
-import com.launchdarkly.sdk.android.DataModel.Flag;
 import com.launchdarkly.sdk.android.subsystems.EventProcessor;
 import com.launchdarkly.sdk.android.subsystems.PersistentDataStore;
 
 import java.io.Closeable;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -198,7 +200,7 @@ public static Future<LDClient> init(@NonNull Application application,
                     resultFuture.setException(e);
                     return resultFuture;
                 }
-            };
+            }
             primaryClient = createdPrimaryClient;
             // this indirect way of setting primaryClient is simply to make it easier to reference
             // it within an inner class below, since it is "effectively final"
@@ -223,9 +225,23 @@ public static Future<LDClient> init(@NonNull Application application,
                 }
             }
 
+            List<RegistrationCompleteResult.Failure.PluginFailure> pluginFailures = new ArrayList<>();
             for (Plugin plugin : instance.plugins) {
                 try {
                     plugin.register(instance, metadata);
+                } catch (Exception e) {
+                    pluginFailures.add(new RegistrationCompleteResult.Failure.PluginFailure(plugin.getMetadata().getName(), e.getMessage(), e));
+                    logger.error("Exception thrown registering plugin " + plugin.getMetadata().getName() + ".");
+                }
+            }
+
+            RegistrationCompleteResult pluginsRegistrationResult = pluginFailures.isEmpty()
+                    ? RegistrationCompleteResult.success()
+                    : RegistrationCompleteResult.failure(pluginFailures);
+
+            for (Plugin plugin : instance.plugins) {
+                try {
+                    plugin.onPluginsReady(pluginsRegistrationResult, metadata);
                 } catch (Exception e) {
                     logger.error("Exception thrown registering plugin " + plugin.getMetadata().getName() + ".");
                 }

launchdarkly-android-client-sdk/src/main/java/com/launchdarkly/sdk/android/integrations/Plugin.java

@@ -26,7 +26,7 @@ public abstract class Plugin {
      * the SDK is configured with multiple environments. Use the metadata to distinguish
      * environments.
      *
-     * @param client for the plugin to use
+     * @param client   for the plugin to use
      * @param metadata metadata about the environment where the plugin is running.
      */
     public abstract void register(LDClient client, EnvironmentMetadata metadata);
@@ -40,11 +40,15 @@ public abstract class Plugin {
      * environments.
      *
      * @param metadata metadata about the environment where the plugin is running.
-     * @return
+     * @return a non-null, possibly empty, list of {@link Hook} instances
      */
     @NonNull
     public List<Hook> getHooks(EnvironmentMetadata metadata) {
         // default impl
         return Collections.emptyList();
     }
+
+    public void onPluginsReady(RegistrationCompleteResult result, EnvironmentMetadata metadata) {
+        // default: do nothing
+    }
 }

launchdarkly-android-client-sdk/src/main/java/com/launchdarkly/sdk/android/integrations/PluginMetadata.java

@@ -6,4 +6,7 @@ public abstract class PluginMetadata {
 
     @NonNull
     public abstract String getName();
+
+    @NonNull
+    public abstract String getVersion();
 }

launchdarkly-android-client-sdk/src/main/java/com/launchdarkly/sdk/android/integrations/RegistrationCompleteResult.kt

@@ -0,0 +1,18 @@
+package com.launchdarkly.sdk.android.integrations
+
+import com.launchdarkly.sdk.android.integrations.RegistrationCompleteResult.Failure.PluginFailure
+
+sealed class RegistrationCompleteResult {
+    object Success : RegistrationCompleteResult()
+    data class Failure(val failures: List<PluginFailure>) : RegistrationCompleteResult() {
+        data class PluginFailure(val pluginName: String, val message: String?, val cause: Throwable?)
+    }
+
+    companion object {
+        @JvmStatic
+        fun success() = Success
+
+        @JvmStatic
+        fun failure(failures: List<PluginFailure>) = Failure(failures)
+    }
+}