From b8e05d298de0b5cfacbdfea4aebca359ccd0b368 Mon Sep 17 00:00:00 2001
From: cvictory <shenglicao2@gmail.com>
Date: Thu, 20 Jun 2019 11:34:26 +0800
Subject: [PATCH] fix empty protocol in consule registry. #4294

---
 .../dubbo/registry/consul/ConsulRegistry.java | 30 +++++++++++++++----
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/dubbo-registry/dubbo-registry-consul/src/main/java/org/apache/dubbo/registry/consul/ConsulRegistry.java b/dubbo-registry/dubbo-registry-consul/src/main/java/org/apache/dubbo/registry/consul/ConsulRegistry.java
index e7cf986cc45..e4832ac6ccc 100644
--- a/dubbo-registry/dubbo-registry-consul/src/main/java/org/apache/dubbo/registry/consul/ConsulRegistry.java
+++ b/dubbo-registry/dubbo-registry-consul/src/main/java/org/apache/dubbo/registry/consul/ConsulRegistry.java
@@ -18,8 +18,10 @@
 package org.apache.dubbo.registry.consul;
 
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.common.URLBuilder;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
+import org.apache.dubbo.common.utils.CollectionUtils;
 import org.apache.dubbo.common.utils.NamedThreadFactory;
 import org.apache.dubbo.registry.NotifyListener;
 import org.apache.dubbo.registry.support.FailbackRegistry;
@@ -49,6 +51,8 @@
 
 import static java.util.concurrent.Executors.newCachedThreadPool;
 import static org.apache.dubbo.common.constants.CommonConstants.ANY_VALUE;
+import static org.apache.dubbo.common.constants.RegistryConstants.CATEGORY_KEY;
+import static org.apache.dubbo.common.constants.RegistryConstants.EMPTY_PROTOCOL;
 import static org.apache.dubbo.registry.Constants.CONSUMER_PROTOCOL;
 import static org.apache.dubbo.registry.Constants.PROVIDER_PROTOCOL;
 
@@ -136,12 +140,12 @@ public void doSubscribe(URL url, NotifyListener listener) {
             Response<Map<String, List<String>>> response = getAllServices(-1, buildWatchTimeout(url));
             index = response.getConsulIndex();
             List<HealthService> services = getHealthServices(response.getValue());
-            urls = convert(services);
+            urls = convert(services, url);
         } else {
             String service = url.getServiceKey();
             Response<List<HealthService>> response = getHealthServices(service, -1, buildWatchTimeout(url));
             index = response.getConsulIndex();
-            urls = convert(response.getValue());
+            urls = convert(response.getValue(), url);
         }
 
         notify(url, listener, urls);
@@ -175,7 +179,7 @@ public List<URL> lookup(URL url) {
             if (result == null || result.getValue() == null || result.getValue().isEmpty()) {
                 return new ArrayList<>();
             } else {
-                return  convert(result.getValue());
+                return convert(result.getValue(), url);
             }
         } catch (Throwable e) {
             throw new RpcException("Failed to lookup " + url + " from consul " + getUrl() + ", cause: " + e.getMessage(), e);
@@ -241,7 +245,10 @@ private boolean isProviderSide(URL url) {
         return url.getProtocol().equals(PROVIDER_PROTOCOL);
     }
 
-    private List<URL> convert(List<HealthService> services) {
+    private List<URL> convert(List<HealthService> services, URL consumerURL) {
+        if (CollectionUtils.isEmpty(services)) {
+            return emptyURL(consumerURL);
+        }
         return services.stream()
                 .map(HealthService::getService)
                 .filter(Objects::nonNull)
@@ -252,6 +259,17 @@ private List<URL> convert(List<HealthService> services) {
                 .collect(Collectors.toList());
     }
 
+    private List<URL> emptyURL(URL consumerURL) {
+        // No Category Parameter
+        URL empty = URLBuilder.from(consumerURL)
+                .setProtocol(EMPTY_PROTOCOL)
+                .removeParameter(CATEGORY_KEY)
+                .build();
+        List<URL> result = new ArrayList<URL>();
+        result.add(empty);
+        return result;
+    }
+
     private NewService buildService(URL url) {
         NewService service = new NewService();
         service.setAddress(url.getHost());
@@ -318,7 +336,7 @@ private void processService() {
             if (currentIndex != null && currentIndex > consulIndex) {
                 consulIndex = currentIndex;
                 List<HealthService> services = response.getValue();
-                List<URL> urls = convert(services);
+                List<URL> urls = convert(services, url);
                 for (NotifyListener listener : getSubscribed().get(url)) {
                     doNotify(url, listener, urls);
                 }
@@ -331,7 +349,7 @@ private void processServices() {
             if (currentIndex != null && currentIndex > consulIndex) {
                 consulIndex = currentIndex;
                 List<HealthService> services = getHealthServices(response.getValue());
-                List<URL> urls = convert(services);
+                List<URL> urls = convert(services, url);
                 for (NotifyListener listener : getSubscribed().get(url)) {
                     doNotify(url, listener, urls);
                 }