Add jvm filter comments and logic refine (#762)

sofa-boot-project/sofa-boot-core/log-sofa-boot/src/main/java/com/alipay/sofa/boot/logging/LogEnvironmentPreparingListener.java

@@ -41,6 +41,7 @@ public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
 
     @Override
     public int getOrder() {
+        // Must be invoked after ConfigFileApplicationListener
         return Ordered.HIGHEST_PRECEDENCE + 100;
     }
 

sofa-boot-project/sofa-boot-core/runtime-sofa-boot/src/main/java/com/alipay/sofa/runtime/filter/JvmFilterContext.java

@@ -24,11 +24,19 @@
  * Created on 2020/8/18
  */
 public class JvmFilterContext {
+    // Jvm invocation result
+    // null when in <code>before</code> invoking except some filter sets it explicitly
     private Object                       invokeResult;
 
+    // Jvm invocation AOP, could be used to fetch method name and args
     private transient MethodInvocation   methodInvocation;
+
+    // In normal SOFABoot application, this is always current application's SOFABoot runtime context
+    // When in Ark environment, this could be Ark Biz's SOFABoot runtime context
     private transient SofaRuntimeContext sofaRuntimeContext;
 
+    // Thrown exception when do Jvm service invoking
+    // null when in <code>before</code> invoking except some filter sets it explicitly
     private Throwable                    exception;
 
     public JvmFilterContext() {

sofa-boot-project/sofa-boot-core/runtime-sofa-boot/src/main/java/com/alipay/sofa/runtime/filter/JvmFilterHolder.java

@@ -67,8 +67,8 @@ public static boolean beforeInvoking(JvmFilterContext context) {
 
     public static boolean afterInvoking(JvmFilterContext context) {
         sortJvmFilters();
-        for (JvmFilter filter : JVM_FILTERS) {
-            if (!filter.after(context)) {
+        for (int i = JVM_FILTERS.size() - 1; i >= 0; --i) {
+            if (!JVM_FILTERS.get(i).after(context)) {
                 return false;
             }
         }

sofa-boot-project/sofa-boot-core/runtime-sofa-boot/src/main/java/com/alipay/sofa/runtime/service/binding/JvmBindingAdapter.java

@@ -154,6 +154,7 @@ public JvmServiceInvoker(Contract contract, JvmBinding binding,
         @Override
         public Object invoke(MethodInvocation invocation) throws Throwable {
             if (!SofaRuntimeProperties.isJvmFilterEnable()) {
+                // Jvm filtering is not enabled
                 return super.invoke(invocation);
             }
 
@@ -166,9 +167,10 @@ public Object invoke(MethodInvocation invocation) throws Throwable {
                     .getDynamicJvmServiceProxyFinder().findServiceComponent(
                         sofaRuntimeContext.getAppClassLoader(), contract);
                 if (serviceComponent == null) {
+                    // Jvm service is not found in normal or Ark environment
+                    // We're actually invoking an RPC service, skip Jvm filtering
                     return super.invoke(invocation);
                 }
-
                 context.setSofaRuntimeContext(serviceComponent.getContext());
             } else {
                 context.setSofaRuntimeContext(sofaRuntimeContext);
@@ -177,15 +179,19 @@ public Object invoke(MethodInvocation invocation) throws Throwable {
             long startTime = System.currentTimeMillis();
             try {
                 Thread.currentThread().setContextClassLoader(serviceClassLoader);
+                // Do Jvm filter <code>before</code> invoking
+                // if some filter returns false, skip remaining filters and actual Jvm invoking
                 if (JvmFilterHolder.beforeInvoking(context)) {
                     rtn = doInvoke(invocation);
                     context.setInvokeResult(rtn);
                 }
             } catch (Throwable e) {
+                // Exception occurs, set <code>e</code> in Jvm context
                 context.setException(e);
                 doCatch(invocation, e, startTime);
                 throw e;
             } finally {
+                // Do Jvm Filter <code>after</code> invoking regardless of the fact whether exception happens or not
                 JvmFilterHolder.afterInvoking(context);
                 rtn = context.getInvokeResult();
                 doFinally(invocation, startTime);
@@ -296,5 +302,4 @@ protected String getUniqueId() {
             return contract.getUniqueId();
         }
     }
-
-}
+}

sofa-boot-project/sofa-boot-core/runtime-sofa-boot/src/main/java/com/alipay/sofa/runtime/service/component/ReferenceComponent.java

@@ -139,6 +139,8 @@ public void activate() throws ServiceRuntimeException {
                     if (JvmBinding.JVM_BINDING_TYPE.getType().equals(binding.getName())) {
                         candidate = binding;
                     } else {
+                        // Under normal RPC reference (local-first/jvm-first is not set to false) binding,
+                        // backup proxy is the RPC proxy, which will be invoked if Jvm service is not found
                         backupProxy = createProxy(reference, binding);
                     }
                 }
@@ -252,4 +254,4 @@ private Object getServiceTarget() {
         }
         return serviceTarget;
     }
-}
+}

sofa-boot-project/sofa-boot-starters/runtime-sofa-boot-starter/src/test/java/com/alipay/sofa/runtime/test/ambush/JvmFilterTest.java

@@ -46,7 +46,7 @@ public static void before() {
 
     @Test
     public void test() {
-        Assert.assertEquals("egressFilter2", myService.say());
+        Assert.assertEquals("egressFilter1", myService.say());
         Assert.assertEquals(5, JvmFilterHolder.getJvmFilters().size());
         Assert.assertEquals(3, JvmFilterTestConfiguration.beforeCount);
         Assert.assertEquals(1, JvmFilterTestConfiguration.afterCount);

sofa-boot-project/sofa-boot-starters/runtime-sofa-boot-starter/src/test/java/com/alipay/sofa/runtime/test/ambush/JvmFilterTestConfiguration.java

@@ -101,7 +101,8 @@ public JvmFilter ingressFilter1() {
             @Override
             public boolean after(JvmFilterContext context) {
                 ++afterCount;
-                return true;
+                context.setInvokeResult("egressFilter1");
+                return false;
             }
 
             @Override
@@ -122,8 +123,7 @@ public JvmFilter ingressFilter2() {
             @Override
             public boolean after(JvmFilterContext context) {
                 ++afterCount;
-                context.setInvokeResult("egressFilter2");
-                return false;
+                return true;
             }
 
             @Override

sofa-boot-project/sofaboot-dependencies/pom.xml

@@ -11,7 +11,7 @@
         <!-- Add this to resolve to repository -->
         <relativePath />
     </parent>
-
+    
     <groupId>com.alipay.sofa</groupId>
     <artifactId>sofaboot-dependencies</artifactId>
     <packaging>pom</packaging>