xds: Update rpc-behavior handling in interop server

Author: murgatroid99

interop-testing/src/main/java/io/grpc/testing/integration/XdsTestServer.java

@@ -59,9 +59,11 @@ public final class XdsTestServer {
       "succeed-on-retry-attempt-";
   private static final String CALL_BEHAVIOR_ERROR_CODE =
       "error-code-";
+  private static final String CALL_BEHAVIOR_HOSTNAME = "hostname=";
   private static final Splitter HEADER_VALUE_SPLITTER = Splitter.on(',')
       .trimResults()
       .omitEmptyStrings();
+  private static final Splitter HEADER_HOSTNAME_SPLITTER = Splitter.on(' ');
 
   private static Logger logger = Logger.getLogger(XdsTestServer.class.getName());
 
@@ -300,8 +302,40 @@ public void sendHeaders(Metadata responseHeaders) {
       };
       ServerCall.Listener<ReqT> noopListener = new ServerCall.Listener<ReqT>() {};
 
-      // sleep if instructed by rpc-behavior
+      int attemptNum = 0;
+      String attemptNumHeader = requestHeaders.get(ATTEMPT_NUM);
+      if (attemptNumHeader != null) {
+        try {
+          attemptNum = Integer.valueOf(attemptNumHeader);
+        } catch (NumberFormatException e) {
+          newCall.close(
+              Status.INVALID_ARGUMENT.withDescription(
+                  String.format(
+                      "Invalid format for grpc-previous-rpc-attempts header (%s)",
+                      attemptNumHeader)),
+              new Metadata());
+          return noopListener;
+        }
+      }
+
       for (String callBehavior : callBehaviors) {
+        if (callBehavior.startsWith(CALL_BEHAVIOR_HOSTNAME)) {
+          List<String> splitHeader = HEADER_HOSTNAME_SPLITTER.splitToList(callBehavior);
+          if (splitHeader.size() > 1) {
+            if (!splitHeader.get(0).substring(CALL_BEHAVIOR_HOSTNAME.length()).equals(host)) {
+              continue;
+            }
+            callBehavior = splitHeader.get(1);
+          } else {
+            newCall.close(
+                Status.INVALID_ARGUMENT.withDescription(
+                    String.format("Invalid format for rpc-behavior header (%s)", callBehavior)),
+                new Metadata()
+            );
+            return noopListener;
+          }
+        }
+
         if (callBehavior.startsWith(CALL_BEHAVIOR_SLEEP_VALUE)) {
           try {
             int timeout = Integer.parseInt(
@@ -321,12 +355,9 @@ public void sendHeaders(Metadata responseHeaders) {
             return noopListener;
           }
         }
-      }
 
-      // succeed the retry attempt if instructed by rpc-behavior
-      int succeedOnAttemptNum = Integer.MAX_VALUE;
-      for (String callBehavior : callBehaviors) {
         if (callBehavior.startsWith(CALL_BEHAVIOR_SUCCEED_ON_RETRY_ATTEMPT_VALUE)) {
+          int succeedOnAttemptNum = Integer.MAX_VALUE;
           try {
             succeedOnAttemptNum = Integer.parseInt(
                 callBehavior.substring(CALL_BEHAVIOR_SUCCEED_ON_RETRY_ATTEMPT_VALUE.length()));
@@ -337,35 +368,16 @@ public void sendHeaders(Metadata responseHeaders) {
                 new Metadata());
             return noopListener;
           }
-          break;
+          if (attemptNum == succeedOnAttemptNum) {
+            return next.startCall(newCall, requestHeaders);
+          }
         }
-      }
-      int attemptNum = 0;
-      String attemptNumHeader = requestHeaders.get(ATTEMPT_NUM);
-      if (attemptNumHeader != null) {
-        try {
-          attemptNum = Integer.valueOf(attemptNumHeader);
-        } catch (NumberFormatException e) {
-          newCall.close(
-              Status.INVALID_ARGUMENT.withDescription(
-                  String.format(
-                      "Invalid format for grpc-previous-rpc-attempts header (%s)",
-                      attemptNumHeader)),
-              new Metadata());
+
+        // hang if instructed by rpc-behavior
+        if (callBehavior.equals(CALL_BEHAVIOR_KEEP_OPEN_VALUE)) {
           return noopListener;
         }
-      }
-      if (attemptNum == succeedOnAttemptNum) {
-        return next.startCall(newCall, requestHeaders);
-      }
 
-      // hang if instructed by rpc-behavior
-      if (callBehaviors.contains(CALL_BEHAVIOR_KEEP_OPEN_VALUE)) {
-        return noopListener;
-      }
-
-      // fail if instructed by rpc-behavior
-      for (String callBehavior : callBehaviors) {
         if (callBehavior.startsWith(CALL_BEHAVIOR_ERROR_CODE)) {
           try {
             int codeValue = Integer.valueOf(