[router] Add SRDS configUpdate impl

include/envoy/router/route_config_provider_manager.h

@@ -33,10 +33,13 @@ class RouteConfigProviderManager {
    * @param rds supplies the proto configuration of an RDS-configured RouteConfigProvider.
    * @param factory_context is the context to use for the route config provider.
    * @param stat_prefix supplies the stat_prefix to use for the provider stats.
+   * @param init_manager the Init::Manager used to coordinate initialization of a the underlying RDS
+   * subscription.
    */
   virtual RouteConfigProviderPtr createRdsRouteConfigProvider(
       const envoy::config::filter::network::http_connection_manager::v2::Rds& rds,
-      Server::Configuration::FactoryContext& factory_context, const std::string& stat_prefix) PURE;
+      Server::Configuration::FactoryContext& factory_context, const std::string& stat_prefix,
+      Init::Manager& init_manager) PURE;
 
   /**
    * Get a RouteConfigSharedPtr for a statically defined route. Ownership is as described for

source/common/config/config_provider_impl.h

@@ -1,7 +1,5 @@
 #pragma once
 
-#include <memory>
-
 #include "envoy/config/config_provider.h"
 #include "envoy/config/config_provider_manager.h"
 #include "envoy/init/manager.h"
@@ -146,9 +144,7 @@ class MutableConfigProviderCommonBase;
  * shared ownership of the underlying subscription.
  *
  */
-class ConfigSubscriptionCommonBase
-    : protected Logger::Loggable<Logger::Id::config>,
-      public std::enable_shared_from_this<ConfigSubscriptionCommonBase> {
+class ConfigSubscriptionCommonBase : protected Logger::Loggable<Logger::Id::config> {
 public:
   // Callback for updating a Config implementation held in each worker thread, the callback is
   // called in applyConfigUpdate() with the current version Config, and is expected to return the
@@ -224,21 +220,14 @@ class ConfigSubscriptionCommonBase
    */
   void applyConfigUpdate(
       const ConfigUpdateCb& update_fn, const Event::PostCb& complete_cb = []() {}) {
-    // It is safe to call shared_from_this here as this is in main thread, and destruction of a
-    // ConfigSubscriptionCommonBase owner (i.e., a provider) happens in main thread as well.
-    auto shared_this = shared_from_this();
     tls_->runOnAllThreads(
         [this, update_fn]() {
-          tls_->getTyped<ThreadLocalConfig>().config_ = update_fn(this->getConfig());
+          // NOTE: there is a known race condition between *this* subscription being teared down in
+          // main thread and the posted callback being executed before the destruction. See more
+          // details in https://github.com/envoyproxy/envoy/issues/7902
+          tls_->getTyped<ThreadLocalConfig>().config_ = update_fn(getConfig());
         },
-        // During the update propagation, a subscription may get teared down in main thread due to
-        // all owners/providers destructed in a xDS update (e.g. LDS demolishes a
-        // RouteConfigProvider and its subscription).
-        // If such a race condition happens, holding a reference to the "*this" subscription
-        // instance in this cb will ensure the shared "*this" gets posted back to main thread, after
-        // all the workers finish calling the update_fn, at which point it's safe to destruct
-        // "*this" instance.
-        [shared_this, complete_cb]() { complete_cb(); });
+        complete_cb);
   }
 
   void setLastUpdated() { last_updated_ = time_source_.systemTime(); }
@@ -287,8 +276,8 @@ class ConfigSubscriptionInstance : public ConfigSubscriptionCommonBase {
 
   /**
    * Must be called by the derived class' constructor.
-   * @param initial_config supplies an initial Envoy::Config::ConfigProvider::Config associated with
-   *                       the underlying subscription, shared across all providers and workers.
+   * @param initial_config supplies an initial Envoy::Config::ConfigProvider::Config associated
+   * with the underlying subscription, shared across all providers and workers.
    */
   void initialize(const ConfigProvider::ConfigConstSharedPtr& initial_config) {
     tls_->set([initial_config](Event::Dispatcher&) -> ThreadLocal::ThreadLocalObjectSharedPtr {
@@ -302,7 +291,8 @@ class ConfigSubscriptionInstance : public ConfigSubscriptionCommonBase {
    * @param config_proto supplies the newly received config proto.
    * @param config_name supplies the name associated with the config.
    * @param version_info supplies the version associated with the config.
-   * @return bool false when the config proto has no delta from the previous config, true otherwise.
+   * @return bool false when the config proto has no delta from the previous config, true
+   * otherwise.
    */
   bool checkAndApplyConfigUpdate(const Protobuf::Message& config_proto,
                                  const std::string& config_name, const std::string& version_info);
@@ -369,8 +359,8 @@ class MutableConfigProviderCommonBase : public ConfigProvider {
 };
 
 /**
- * Provides generic functionality required by all config provider managers, such as managing shared
- * lifetime of subscriptions and dynamic config providers, along with determining which
+ * Provides generic functionality required by all config provider managers, such as managing
+ * shared lifetime of subscriptions and dynamic config providers, along with determining which
  * subscriptions should be associated with newly instantiated providers.
  *
  * The implementation of this class is not thread safe. Note that ImmutableConfigProviderBase
@@ -379,9 +369,9 @@ class MutableConfigProviderCommonBase : public ConfigProvider {
  *
  * All config processing is done on the main thread, so instantiation of *ConfigProvider* objects
  * via createStaticConfigProvider() and createXdsConfigProvider() is naturally thread safe. Care
- * must be taken with regards to destruction of these objects, since it must also happen on the main
- * thread _prior_ to destruction of the ConfigProviderManagerImplBase object from which they were
- * created.
+ * must be taken with regards to destruction of these objects, since it must also happen on the
+ * main thread _prior_ to destruction of the ConfigProviderManagerImplBase object from which they
+ * were created.
  *
  * This class can not be instantiated directly; instead, it provides the foundation for
  * dynamic config provider implementations which derive from it.
@@ -415,8 +405,8 @@ class ConfigProviderManagerImplBase : public ConfigProviderManager, public Singl
   const ConfigProviderSet& immutableConfigProviders(ConfigProviderInstanceType type) const;
 
   /**
-   * Returns the subscription associated with the config_source_proto; if none exists, a new one is
-   * allocated according to the subscription_factory_fn.
+   * Returns the subscription associated with the config_source_proto; if none exists, a new one
+   * is allocated according to the subscription_factory_fn.
    * @param config_source_proto supplies the proto specifying the config subscription parameters.
    * @param init_manager supplies the init manager.
    * @param subscription_factory_fn supplies a function to be called when a new subscription needs

source/common/router/BUILD

@@ -132,6 +132,7 @@ envoy_cc_library(
         "//include/envoy/singleton:instance_interface",
         "//include/envoy/thread_local:thread_local_interface",
         "//source/common/common:assert_lib",
+        "//source/common/common:callback_impl_lib",
         "//source/common/common:minimal_logger_lib",
         "//source/common/config:rds_json_lib",
         "//source/common/config:subscription_factory_lib",
@@ -146,22 +147,16 @@ envoy_cc_library(
     ],
 )
 
-envoy_cc_library(
-    name = "scoped_config_manager_lib",
-    srcs = ["scoped_config_manager.cc"],
-    hdrs = ["scoped_config_manager.h"],
-    deps = [
-        "@envoy_api//envoy/api/v2:srds_cc",
-    ],
-)
-
 envoy_cc_library(
     name = "scoped_config_lib",
     srcs = ["scoped_config_impl.cc"],
     hdrs = ["scoped_config_impl.h"],
+    external_deps = [
+        "abseil_str_format",
+    ],
     deps = [
         ":config_lib",
-        ":scoped_config_manager_lib",
+        "//include/envoy/router:rds_interface",
         "//include/envoy/router:scopes_interface",
         "//include/envoy/thread_local:thread_local_interface",
         "@envoy_api//envoy/api/v2:srds_cc",
@@ -174,13 +169,18 @@ envoy_cc_library(
     srcs = ["scoped_rds.cc"],
     hdrs = ["scoped_rds.h"],
     deps = [
+        ":rds_lib",
         ":scoped_config_lib",
         "//include/envoy/config:config_provider_interface",
         "//include/envoy/config:subscription_interface",
+        "//include/envoy/router:route_config_provider_manager_interface",
         "//include/envoy/stats:stats_interface",
         "//source/common/common:assert_lib",
+        "//source/common/common:cleanup_lib",
         "//source/common/common:minimal_logger_lib",
         "//source/common/config:config_provider_lib",
+        "//source/common/init:manager_lib",
+        "//source/common/init:watcher_lib",
         "@envoy_api//envoy/admin/v2alpha:config_dump_cc",
         "@envoy_api//envoy/api/v2:srds_cc",
     ],

source/common/router/rds_impl.cc

@@ -30,8 +30,8 @@ RouteConfigProviderPtr RouteConfigProviderUtil::create(
     return route_config_provider_manager.createStaticRouteConfigProvider(config.route_config(),
                                                                          factory_context);
   case envoy::config::filter::network::http_connection_manager::v2::HttpConnectionManager::kRds:
-    return route_config_provider_manager.createRdsRouteConfigProvider(config.rds(), factory_context,
-                                                                      stat_prefix);
+    return route_config_provider_manager.createRdsRouteConfigProvider(
+        config.rds(), factory_context, stat_prefix, factory_context.initManager());
   default:
     NOT_REACHED_GCOVR_EXCL_LINE;
   }
@@ -120,6 +120,7 @@ void RdsRouteConfigSubscription::onConfigUpdate(
       }
       vhds_subscription_.release();
     }
+    update_callback_manager_.runCallbacks();
   }
 
   init_target_.ready();
@@ -208,8 +209,8 @@ RouteConfigProviderManagerImpl::RouteConfigProviderManagerImpl(Server::Admin& ad
 
 Router::RouteConfigProviderPtr RouteConfigProviderManagerImpl::createRdsRouteConfigProvider(
     const envoy::config::filter::network::http_connection_manager::v2::Rds& rds,
-    Server::Configuration::FactoryContext& factory_context, const std::string& stat_prefix) {
-
+    Server::Configuration::FactoryContext& factory_context, const std::string& stat_prefix,
+    Init::Manager& init_manager) {
   // RdsRouteConfigSubscriptions are unique based on their serialized RDS config.
   const uint64_t manager_identifier = MessageUtil::hash(rds);
 
@@ -222,9 +223,7 @@ Router::RouteConfigProviderPtr RouteConfigProviderManagerImpl::createRdsRouteCon
     // of simplicity.
     subscription.reset(new RdsRouteConfigSubscription(rds, manager_identifier, factory_context,
                                                       stat_prefix, *this));
-
-    factory_context.initManager().add(subscription->init_target_);
-
+    init_manager.add(subscription->init_target_);
     route_config_subscriptions_.insert({manager_identifier, subscription});
   } else {
     // Because the RouteConfigProviderManager's weak_ptrs only get cleaned up

source/common/router/rds_impl.h

@@ -22,6 +22,7 @@
 #include "envoy/stats/scope.h"
 #include "envoy/thread_local/thread_local.h"
 
+#include "common/common/callback_impl.h"
 #include "common/common/logger.h"
 #include "common/init/target_impl.h"
 #include "common/protobuf/utility.h"
@@ -31,6 +32,9 @@
 namespace Envoy {
 namespace Router {
 
+// For friend class declaration in RdsRouteConfigSubscription.
+class ScopedRdsConfigSubscription;
+
 /**
  * Route configuration provider utilities.
  */
@@ -122,6 +126,10 @@ class RdsRouteConfigSubscription : Envoy::Config::SubscriptionCallbacks,
         .name();
   }
 
+  Common::CallbackHandle* addUpdateCallback(std::function<void()> callback) {
+    return update_callback_manager_.add(callback);
+  }
+
   RdsRouteConfigSubscription(
       const envoy::config::filter::network::http_connection_manager::v2::Rds& rds,
       const uint64_t manager_identifier, Server::Configuration::FactoryContext& factory_context,
@@ -143,8 +151,11 @@ class RdsRouteConfigSubscription : Envoy::Config::SubscriptionCallbacks,
   VhdsSubscriptionPtr vhds_subscription_;
   RouteConfigUpdatePtr config_update_info_;
   ProtobufMessage::ValidationVisitor& validation_visitor_;
+  Common::CallbackManager<> update_callback_manager_;
 
   friend class RouteConfigProviderManagerImpl;
+  // Access to addUpdateCallback
+  friend class ScopedRdsConfigSubscription;
 };
 
 using RdsRouteConfigSubscriptionSharedPtr = std::shared_ptr<RdsRouteConfigSubscription>;
@@ -195,8 +206,8 @@ class RouteConfigProviderManagerImpl : public RouteConfigProviderManager,
   // RouteConfigProviderManager
   RouteConfigProviderPtr createRdsRouteConfigProvider(
       const envoy::config::filter::network::http_connection_manager::v2::Rds& rds,
-      Server::Configuration::FactoryContext& factory_context,
-      const std::string& stat_prefix) override;
+      Server::Configuration::FactoryContext& factory_context, const std::string& stat_prefix,
+      Init::Manager& init_manager) override;
 
   RouteConfigProviderPtr
   createStaticRouteConfigProvider(const envoy::api::v2::RouteConfiguration& route_config,

source/common/router/scoped_config_impl.cc

@@ -10,13 +10,7 @@ bool ScopeKey::operator==(const ScopeKey& other) const {
     // An empty key equals to nothing, "NULL" != "NULL".
     return false;
   }
-  return std::equal(fragments_.begin(), fragments_.end(), other.fragments_.begin(),
-                    other.fragments_.end(),
-                    [](const std::unique_ptr<ScopeKeyFragmentBase>& left,
-                       const std::unique_ptr<ScopeKeyFragmentBase>& right) -> bool {
-                      // Both should be non-NULL now.
-                      return *left == *right;
-                    });
+  return this->hash() == other.hash();
 }
 
 HeaderValueExtractorImpl::HeaderValueExtractorImpl(
@@ -76,6 +70,22 @@ HeaderValueExtractorImpl::computeFragment(const Http::HeaderMap& headers) const
   return nullptr;
 }
 
+ScopedRouteInfo::ScopedRouteInfo(envoy::api::v2::ScopedRouteConfiguration&& config_proto,
+                                 ConfigConstSharedPtr&& route_config)
+    : config_proto_(std::move(config_proto)), route_config_(std::move(route_config)) {
+  // TODO(stevenzzzz): Maybe worth a KeyBuilder abstraction when there are more than one type of
+  // Fragment.
+  for (const auto& fragment : config_proto_.key().fragments()) {
+    switch (fragment.type_case()) {
+    case envoy::api::v2::ScopedRouteConfiguration::Key::Fragment::kStringKey:
+      scope_key_.addFragment(std::make_unique<StringKeyFragment>(fragment.string_key()));
+      break;
+    default:
+      NOT_REACHED_GCOVR_EXCL_LINE;
+    }
+  }
+}
+
 ScopeKeyBuilderImpl::ScopeKeyBuilderImpl(ScopedRoutes::ScopeKeyBuilder&& config)
     : ScopeKeyBuilderBase(std::move(config)) {
   for (const auto& fragment_builder : config_.fragments()) {
@@ -104,12 +114,37 @@ ScopeKeyBuilderImpl::computeScopeKey(const Http::HeaderMap& headers) const {
   return std::make_unique<ScopeKey>(std::move(key));
 }
 
-void ScopedConfigImpl::addOrUpdateRoutingScope(const ScopedRouteInfoConstSharedPtr&) {}
+void ScopedConfigImpl::addOrUpdateRoutingScope(
+    const ScopedRouteInfoConstSharedPtr& scoped_route_info) {
+  const auto iter = scoped_route_info_by_name_.find(scoped_route_info->scopeName());
+  if (iter != scoped_route_info_by_name_.end()) {
+    ASSERT(scoped_route_info_by_key_.contains(iter->second->scopeKey().hash()));
+    scoped_route_info_by_key_.erase(iter->second->scopeKey().hash());
+  }
+  scoped_route_info_by_name_[scoped_route_info->scopeName()] = scoped_route_info;
+  scoped_route_info_by_key_[scoped_route_info->scopeKey().hash()] = scoped_route_info;
+}
 
-void ScopedConfigImpl::removeRoutingScope(const std::string&) {}
+void ScopedConfigImpl::removeRoutingScope(const std::string& scope_name) {
+  const auto iter = scoped_route_info_by_name_.find(scope_name);
+  if (iter != scoped_route_info_by_name_.end()) {
+    ASSERT(scoped_route_info_by_key_.contains(iter->second->scopeKey().hash()));
+    scoped_route_info_by_key_.erase(iter->second->scopeKey().hash());
+    scoped_route_info_by_name_.erase(iter);
+  }
+}
 
-Router::ConfigConstSharedPtr ScopedConfigImpl::getRouteConfig(const Http::HeaderMap&) const {
-  return std::make_shared<const NullConfigImpl>();
+Router::ConfigConstSharedPtr
+ScopedConfigImpl::getRouteConfig(const Http::HeaderMap& headers) const {
+  std::unique_ptr<ScopeKey> scope_key = scope_key_builder_.computeScopeKey(headers);
+  if (scope_key == nullptr) {
+    return nullptr;
+  }
+  auto iter = scoped_route_info_by_key_.find(scope_key->hash());
+  if (iter != scoped_route_info_by_key_.end()) {
+    return iter->second->routeConfig();
+  }
+  return nullptr;
 }
 
 } // namespace Router