feat: support incremental configuration synchronization client

apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/config/BizConfig.java

@@ -240,6 +240,11 @@ public boolean isConfigServiceCacheKeyIgnoreCase() {
     return getBooleanProperty("config-service.cache.key.ignore-case", false);
   }
 
+  public boolean isConfigServiceChangeCacheEnabled() {
+    return getBooleanProperty("config-service.change.cache.enabled", false);
+  }
+
+
   int checkInt(int value, int min, int max, int defaultValue) {
     if (value >= min && value <= max) {
       return value;

apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/repository/ReleaseRepository.java

@@ -37,13 +37,15 @@ Release findFirstByAppIdAndClusterNameAndNamespaceNameAndIsAbandonedFalseOrderBy
 
   Release findByIdAndIsAbandonedFalse(long id);
 
+  Release findByReleaseKey(String releaseKey);
+
   List<Release> findByAppIdAndClusterNameAndNamespaceNameOrderByIdDesc(String appId, String clusterName, String namespaceName, Pageable page);
 
   List<Release> findByAppIdAndClusterNameAndNamespaceNameAndIsAbandonedFalseOrderByIdDesc(String appId, String clusterName, String namespaceName, Pageable page);
 
   List<Release> findByAppIdAndClusterNameAndNamespaceNameAndIsAbandonedFalseAndIdBetweenOrderByIdDesc(String appId, String clusterName, String namespaceName, long fromId, long toId);
 
-  List<Release> findByReleaseKeyIn(Set<String> releaseKey);
+  List<Release> findByReleaseKeyIn(Set<String> releaseKeys);
 
   List<Release> findByIdIn(Set<Long> releaseIds);
 

apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/service/ReleaseService.java

@@ -119,6 +119,10 @@ public List<Release> findByReleaseKeys(Set<String> releaseKeys) {
     return releaseRepository.findByReleaseKeyIn(releaseKeys);
   }
 
+  public Release findByReleaseKey(String releaseKey) {
+    return releaseRepository.findByReleaseKey(releaseKey);
+  }
+
   public Release findLatestActiveRelease(Namespace namespace) {
     return findLatestActiveRelease(namespace.getAppId(),
                                    namespace.getClusterName(), namespace.getNamespaceName());

apollo-configservice/src/main/java/com/ctrip/framework/apollo/configservice/ConfigServiceAutoConfiguration.java

@@ -30,6 +30,7 @@
 import com.ctrip.framework.apollo.configservice.service.ReleaseMessageServiceWithCache;
 import com.ctrip.framework.apollo.configservice.service.config.ConfigService;
 import com.ctrip.framework.apollo.configservice.service.config.ConfigServiceWithCache;
+import com.ctrip.framework.apollo.configservice.service.config.ConfigServiceWithChangeCache;
 import com.ctrip.framework.apollo.configservice.service.config.DefaultConfigService;
 import com.ctrip.framework.apollo.configservice.util.AccessKeyUtil;
 import io.micrometer.core.instrument.MeterRegistry;
@@ -73,9 +74,12 @@ public ConfigService configService() {
       return new ConfigServiceWithCache(releaseService, releaseMessageService,
           grayReleaseRulesHolder(), bizConfig, meterRegistry);
     }
+    if(bizConfig.isConfigServiceChangeCacheEnabled()){
+      return new ConfigServiceWithChangeCache(releaseService, releaseMessageService,
+		      grayReleaseRulesHolder(), bizConfig, meterRegistry);
+    }
     return new DefaultConfigService(releaseService, grayReleaseRulesHolder());
   }
-
   @Bean
   public static NoOpPasswordEncoder passwordEncoder() {
     return (NoOpPasswordEncoder) NoOpPasswordEncoder.getInstance();

apollo-configservice/src/main/java/com/ctrip/framework/apollo/configservice/controller/ConfigController.java

@@ -16,6 +16,7 @@
  */
 package com.ctrip.framework.apollo.configservice.controller;
 
+import com.ctrip.framework.apollo.biz.config.BizConfig;
 import com.ctrip.framework.apollo.biz.entity.Release;
 import com.ctrip.framework.apollo.common.entity.AppNamespace;
 import com.ctrip.framework.apollo.common.utils.WebUtils;
@@ -26,10 +27,13 @@
 import com.ctrip.framework.apollo.core.ConfigConsts;
 import com.ctrip.framework.apollo.core.dto.ApolloConfig;
 import com.ctrip.framework.apollo.core.dto.ApolloNotificationMessages;
+import com.ctrip.framework.apollo.core.dto.ConfigurationChange;
+import com.ctrip.framework.apollo.core.enums.ConfigSyncType;
 import com.ctrip.framework.apollo.tracer.Tracer;
 import com.google.common.base.Strings;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
 import com.google.gson.Gson;
 import com.google.gson.reflect.TypeToken;
 import org.springframework.web.bind.annotation.GetMapping;
@@ -42,6 +46,9 @@
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 import java.lang.reflect.Type;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -59,32 +66,36 @@ public class ConfigController {
   private final NamespaceUtil namespaceUtil;
   private final InstanceConfigAuditUtil instanceConfigAuditUtil;
   private final Gson gson;
+  private final BizConfig bizConfig;
+
 
   private static final Type configurationTypeReference = new TypeToken<Map<String, String>>() {
-      }.getType();
+  }.getType();
 
   public ConfigController(
       final ConfigService configService,
       final AppNamespaceServiceWithCache appNamespaceService,
       final NamespaceUtil namespaceUtil,
       final InstanceConfigAuditUtil instanceConfigAuditUtil,
-      final Gson gson) {
+      final Gson gson,
+      final BizConfig bizConfig) {
     this.configService = configService;
     this.appNamespaceService = appNamespaceService;
     this.namespaceUtil = namespaceUtil;
     this.instanceConfigAuditUtil = instanceConfigAuditUtil;
     this.gson = gson;
+    this.bizConfig = bizConfig;
   }
 
   @GetMapping(value = "/{appId}/{clusterName}/{namespace:.+}")
   public ApolloConfig queryConfig(@PathVariable String appId, @PathVariable String clusterName,
-                                  @PathVariable String namespace,
-                                  @RequestParam(value = "dataCenter", required = false) String dataCenter,
-                                  @RequestParam(value = "releaseKey", defaultValue = "-1") String clientSideReleaseKey,
-                                  @RequestParam(value = "ip", required = false) String clientIp,
-                                  @RequestParam(value = "label", required = false) String clientLabel,
-                                  @RequestParam(value = "messages", required = false) String messagesAsString,
-                                  HttpServletRequest request, HttpServletResponse response) throws IOException {
+      @PathVariable String namespace,
+      @RequestParam(value = "dataCenter", required = false) String dataCenter,
+      @RequestParam(value = "releaseKey", defaultValue = "-1") String clientSideReleaseKey,
+      @RequestParam(value = "ip", required = false) String clientIp,
+      @RequestParam(value = "label", required = false) String clientLabel,
+      @RequestParam(value = "messages", required = false) String messagesAsString,
+      HttpServletRequest request, HttpServletResponse response) throws IOException {
     String originalNamespace = namespace;
     //strip out .properties suffix
     namespace = namespaceUtil.filterNamespaceName(namespace);
@@ -101,7 +112,8 @@ public ApolloConfig queryConfig(@PathVariable String appId, @PathVariable String
 
     String appClusterNameLoaded = clusterName;
     if (!ConfigConsts.NO_APPID_PLACEHOLDER.equalsIgnoreCase(appId)) {
-      Release currentAppRelease = configService.loadConfig(appId, clientIp, clientLabel, appId, clusterName, namespace,
+      Release currentAppRelease = configService.loadConfig(appId, clientIp, clientLabel, appId,
+          clusterName, namespace,
           dataCenter, clientMessages);
 
       if (currentAppRelease != null) {
@@ -113,7 +125,8 @@ public ApolloConfig queryConfig(@PathVariable String appId, @PathVariable String
 
     //if namespace does not belong to this appId, should check if there is a public configuration
     if (!namespaceBelongsToAppId(appId, namespace)) {
-      Release publicRelease = this.findPublicConfig(appId, clientIp, clientLabel, clusterName, namespace,
+      Release publicRelease = this.findPublicConfig(appId, clientIp, clientLabel, clusterName,
+          namespace,
           dataCenter, clientMessages);
       if (Objects.nonNull(publicRelease)) {
         releases.add(publicRelease);
@@ -132,10 +145,10 @@ public ApolloConfig queryConfig(@PathVariable String appId, @PathVariable String
 
     auditReleases(appId, clusterName, dataCenter, clientIp, releases);
 
-    String mergedReleaseKey = releases.stream().map(Release::getReleaseKey)
-            .collect(Collectors.joining(ConfigConsts.CLUSTER_NAMESPACE_SEPARATOR));
+    String latestMergedReleaseKey = releases.stream().map(Release::getReleaseKey)
+        .collect(Collectors.joining(ConfigConsts.CLUSTER_NAMESPACE_SEPARATOR));
 
-    if (mergedReleaseKey.equals(clientSideReleaseKey)) {
+    if (latestMergedReleaseKey.equals(clientSideReleaseKey)) {
       // Client side configuration is the same with server side, return 304
       response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
       Tracer.logEvent("Apollo.Config.NotModified",
@@ -144,8 +157,42 @@ public ApolloConfig queryConfig(@PathVariable String appId, @PathVariable String
     }
 
     ApolloConfig apolloConfig = new ApolloConfig(appId, appClusterNameLoaded, originalNamespace,
-        mergedReleaseKey);
-    apolloConfig.setConfigurations(mergeReleaseConfigurations(releases));
+        latestMergedReleaseKey);
+
+    Map<String, String> latestConfigurations = mergeReleaseConfigurations(releases);
+
+    if (bizConfig.isConfigServiceChangeCacheEnabled()) {
+      LinkedHashSet<String> clientSideReleaseKeys = Sets.newLinkedHashSet(
+          Arrays.stream(clientSideReleaseKey.split("\\+")).collect(Collectors.toList()));
+
+      Map<String, Release> historyReleases = configService.findReleasesByReleaseKeys(
+          clientSideReleaseKeys);
+      //find history releases
+      if (historyReleases != null) {
+        //order by clientSideReleaseKeys
+        List<Release> historyReleasesWithOrder = new ArrayList<>();
+        for (String item : clientSideReleaseKeys) {
+          Release release = historyReleases.get(item);
+          if (release != null) {
+            historyReleasesWithOrder.add(release);
+          }
+        }
+
+        Map<String, String> historyConfigurations = mergeReleaseConfigurations
+            (historyReleasesWithOrder);
+
+        List<ConfigurationChange> configurationChanges = configService.calcConfigurationChanges(
+            latestConfigurations, historyConfigurations);
+
+        apolloConfig.setConfigurationChanges(configurationChanges);
+
+        apolloConfig.setConfigSyncType(ConfigSyncType.INCREMENTALSYNC.getValue());
+        return apolloConfig;
+      }
+
+    }
+
+    apolloConfig.setConfigurations(latestConfigurations);
 
     Tracer.logEvent("Apollo.Config.Found", assembleKey(appId, appClusterNameLoaded,
         originalNamespace, dataCenter));
@@ -173,8 +220,9 @@ private boolean namespaceBelongsToAppId(String appId, String namespaceName) {
    * @param namespace   the namespace
    * @param dataCenter  the datacenter
    */
-  private Release findPublicConfig(String clientAppId, String clientIp, String clientLabel, String clusterName,
-                                   String namespace, String dataCenter, ApolloNotificationMessages clientMessages) {
+  private Release findPublicConfig(String clientAppId, String clientIp, String clientLabel,
+      String clusterName,
+      String namespace, String dataCenter, ApolloNotificationMessages clientMessages) {
     AppNamespace appNamespace = appNamespaceService.findPublicNamespaceByName(namespace);
 
     //check whether the namespace's appId equals to current one
@@ -184,13 +232,13 @@ private Release findPublicConfig(String clientAppId, String clientIp, String cli
 
     String publicConfigAppId = appNamespace.getAppId();
 
-    return configService.loadConfig(clientAppId, clientIp, clientLabel, publicConfigAppId, clusterName, namespace, dataCenter,
+    return configService.loadConfig(clientAppId, clientIp, clientLabel, publicConfigAppId,
+        clusterName, namespace, dataCenter,
         clientMessages);
   }
 
   /**
-   * Merge configurations of releases.
-   * Release in lower index override those in higher index
+   * Merge configurations of releases. Release in lower index override those in higher index
    */
   Map<String, String> mergeReleaseConfigurations(List<Release> releases) {
     Map<String, String> result = Maps.newLinkedHashMap();
@@ -209,7 +257,7 @@ private String assembleKey(String appId, String cluster, String namespace, Strin
   }
 
   private void auditReleases(String appId, String cluster, String dataCenter, String clientIp,
-                             List<Release> releases) {
+      List<Release> releases) {
     if (Strings.isNullOrEmpty(clientIp)) {
       //no need to audit instance config when there is no ip
       return;

apollo-configservice/src/main/java/com/ctrip/framework/apollo/configservice/service/config/AbstractConfigService.java

@@ -21,9 +21,17 @@
 import com.ctrip.framework.apollo.core.ConfigConsts;
 import com.ctrip.framework.apollo.core.dto.ApolloNotificationMessages;
 
+import com.ctrip.framework.apollo.core.dto.ConfigurationChange;
+import com.ctrip.framework.apollo.core.enums.ConfigurationChangeType;
 import com.google.common.base.Strings;
 
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import java.util.Objects;
+import java.util.Set;
 
 /**
  * @author Jason Song([email protected])
@@ -37,11 +45,13 @@ protected AbstractConfigService(final GrayReleaseRulesHolder grayReleaseRulesHol
   }
 
   @Override
-  public Release loadConfig(String clientAppId, String clientIp, String clientLabel, String configAppId, String configClusterName,
+  public Release loadConfig(String clientAppId, String clientIp, String clientLabel,
+      String configAppId, String configClusterName,
       String configNamespace, String dataCenter, ApolloNotificationMessages clientMessages) {
     // load from specified cluster first
     if (!Objects.equals(ConfigConsts.CLUSTER_NAME_DEFAULT, configClusterName)) {
-      Release clusterRelease = findRelease(clientAppId, clientIp, clientLabel, configAppId, configClusterName, configNamespace,
+      Release clusterRelease = findRelease(clientAppId, clientIp, clientLabel, configAppId,
+          configClusterName, configNamespace,
           clientMessages);
 
       if (Objects.nonNull(clusterRelease)) {
@@ -51,33 +61,37 @@ public Release loadConfig(String clientAppId, String clientIp, String clientLabe
 
     // try to load via data center
     if (!Strings.isNullOrEmpty(dataCenter) && !Objects.equals(dataCenter, configClusterName)) {
-      Release dataCenterRelease = findRelease(clientAppId, clientIp, clientLabel, configAppId, dataCenter, configNamespace,
+      Release dataCenterRelease = findRelease(clientAppId, clientIp, clientLabel, configAppId,
+          dataCenter, configNamespace,
           clientMessages);
       if (Objects.nonNull(dataCenterRelease)) {
         return dataCenterRelease;
       }
     }
 
     // fallback to default release
-    return findRelease(clientAppId, clientIp, clientLabel, configAppId, ConfigConsts.CLUSTER_NAME_DEFAULT, configNamespace,
+    return findRelease(clientAppId, clientIp, clientLabel, configAppId,
+        ConfigConsts.CLUSTER_NAME_DEFAULT, configNamespace,
         clientMessages);
   }
 
   /**
    * Find release
    *
-   * @param clientAppId the client's app id
-   * @param clientIp the client ip
-   * @param clientLabel the client label
-   * @param configAppId the requested config's app id
+   * @param clientAppId       the client's app id
+   * @param clientIp          the client ip
+   * @param clientLabel       the client label
+   * @param configAppId       the requested config's app id
    * @param configClusterName the requested config's cluster name
-   * @param configNamespace the requested config's namespace name
-   * @param clientMessages the messages received in client side
+   * @param configNamespace   the requested config's namespace name
+   * @param clientMessages    the messages received in client side
    * @return the release
    */
-  private Release findRelease(String clientAppId, String clientIp, String clientLabel, String configAppId, String configClusterName,
+  private Release findRelease(String clientAppId, String clientIp, String clientLabel,
+      String configAppId, String configClusterName,
       String configNamespace, ApolloNotificationMessages clientMessages) {
-    Long grayReleaseId = grayReleaseRulesHolder.findReleaseIdFromGrayReleaseRule(clientAppId, clientIp, clientLabel, configAppId,
+    Long grayReleaseId = grayReleaseRulesHolder.findReleaseIdFromGrayReleaseRule(clientAppId,
+        clientIp, clientLabel, configAppId,
         configClusterName, configNamespace);
 
     Release release = null;
@@ -87,12 +101,59 @@ private Release findRelease(String clientAppId, String clientIp, String clientLa
     }
 
     if (release == null) {
-      release = findLatestActiveRelease(configAppId, configClusterName, configNamespace, clientMessages);
+      release = findLatestActiveRelease(configAppId, configClusterName, configNamespace,
+          clientMessages);
     }
 
     return release;
   }
 
+  public List<ConfigurationChange> calcConfigurationChanges(
+      Map<String, String> latestReleaseConfigurations, Map<String, String> historyConfigurations) {
+    if (latestReleaseConfigurations == null) {
+      latestReleaseConfigurations = new HashMap<>();
+    }
+
+    if (historyConfigurations == null) {
+      historyConfigurations = new HashMap<>();
+    }
+
+    Set<String> previousKeys = historyConfigurations.keySet();
+    Set<String> currentKeys = latestReleaseConfigurations.keySet();
+
+    Set<String> commonKeys = Sets.intersection(previousKeys, currentKeys);
+    Set<String> newKeys = Sets.difference(currentKeys, commonKeys);
+    Set<String> removedKeys = Sets.difference(previousKeys, commonKeys);
+
+    List<ConfigurationChange> changes = Lists.newArrayList();
+
+    for (String newKey : newKeys) {
+      changes.add(new ConfigurationChange(newKey, latestReleaseConfigurations.get(newKey),
+          "ADDED"));
+    }
+
+    for (String removedKey : removedKeys) {
+      changes.add(new ConfigurationChange(removedKey, null, "DELETED"));
+    }
+
+    for (String commonKey : commonKeys) {
+      String previousValue = historyConfigurations.get(commonKey);
+      String currentValue = latestReleaseConfigurations.get(commonKey);
+      if (com.google.common.base.Objects.equal(previousValue, currentValue)) {
+        continue;
+      }
+      changes.add(
+          new ConfigurationChange(commonKey, currentValue, "MODIFIED"));
+    }
+
+    return changes;
+  }
+
+  @Override
+  public Map<String, Release> findReleasesByReleaseKeys(Set<String> releaseKeys) {
+    return null;
+  }
+
   /**
    * Find active release by id
    */