SERVER-9043/SERVER-31156 Link flushRouterConfig on MongoD and make it accept a namespace argument

(cherry picked from commit e4f26d25632f94a6577028ccefd32069550628b6)
(cherry picked from commit dbcfdd8a27453e2ff552bcaa6679aac1cbc1d428)

15 files changed, 105 insertions, 38 deletions

diff --git a/src/mongo/client/replica_set_monitor.cpp b/src/mongo/client/replica_set_monitor.cpp
index 33c7ddb545f..815328c3aed 100644
--- a/src/mongo/client/replica_set_monitor.cpp
+++ b/src/mongo/client/replica_set_monitor.cpp
@@ -45,7 +45,6 @@
 #include "mongo/db/operation_context.h"
 #include "mongo/db/repl/bson_extract_optime.h"
 #include "mongo/db/server_options.h"
-#include "mongo/s/grid.h"
 #include "mongo/stdx/condition_variable.h"
 #include "mongo/stdx/mutex.h"
 #include "mongo/stdx/thread.h"
diff --git a/src/mongo/db/auth/authz_session_external_state_s.cpp b/src/mongo/db/auth/authz_session_external_state_s.cpp
index 457f536038e..c04b2448a4c 100644
--- a/src/mongo/db/auth/authz_session_external_state_s.cpp
+++ b/src/mongo/db/auth/authz_session_external_state_s.cpp
@@ -36,7 +36,6 @@
 #include "mongo/client/dbclientinterface.h"
 #include "mongo/db/auth/authorization_manager.h"
 #include "mongo/db/jsobj.h"
-#include "mongo/s/grid.h"
 
 namespace mongo {
 
diff --git a/src/mongo/db/catalog/coll_mod.cpp b/src/mongo/db/catalog/coll_mod.cpp
index 455b82da31b..b79557d86af 100644
--- a/src/mongo/db/catalog/coll_mod.cpp
+++ b/src/mongo/db/catalog/coll_mod.cpp
@@ -55,12 +55,10 @@
 #include "mongo/s/catalog/type_collection.h"
 #include "mongo/s/client/shard_registry.h"
 #include "mongo/s/grid.h"
-#include "mongo/s/sharding_initialization.h"
 #include "mongo/util/fail_point_service.h"
 #include "mongo/util/log.h"
 
 namespace mongo {
-
 namespace {
 
 // Causes the server to hang when it attempts to assign UUIDs to the provided database (or all
diff --git a/src/mongo/db/cloner.cpp b/src/mongo/db/cloner.cpp
index 71bca81f279..34867aa9623 100644
--- a/src/mongo/db/cloner.cpp
+++ b/src/mongo/db/cloner.cpp
@@ -65,7 +65,6 @@
 #include "mongo/db/server_parameters.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/storage/storage_options.h"
-#include "mongo/s/grid.h"
 #include "mongo/util/assert_util.h"
 #include "mongo/util/log.h"
 #include "mongo/util/mongoutils/str.h"
diff --git a/src/mongo/db/s/balancer/balancer.cpp b/src/mongo/db/s/balancer/balancer.cpp
index 30d766726bf..6dcf93c5293 100644
--- a/src/mongo/db/s/balancer/balancer.cpp
+++ b/src/mongo/db/s/balancer/balancer.cpp
@@ -385,7 +385,7 @@ void Balancer::_mainThread() {
 
                     shardingContext->catalogClient()
                         ->logAction(opCtx.get(), "balancer.round", "", roundDetails.toBSON())
-                        .transitional_ignore();
+                        .ignore();
                 }
 
                 LOG(1) << "*** End of balancing round";
diff --git a/src/mongo/db/s/sharding_server_status.cpp b/src/mongo/db/s/sharding_server_status.cpp
index 5cee3021388..894bc6cb43c 100644
--- a/src/mongo/db/s/sharding_server_status.cpp
+++ b/src/mongo/db/s/sharding_server_status.cpp
@@ -34,19 +34,15 @@
 #include "mongo/db/commands/server_status.h"
 #include "mongo/db/s/sharding_state.h"
 #include "mongo/db/s/sharding_statistics.h"
-#include "mongo/db/server_options.h"
 #include "mongo/s/balancer_configuration.h"
 #include "mongo/s/catalog_cache.h"
 #include "mongo/s/client/shard_registry.h"
 #include "mongo/s/grid.h"
+#include "mongo/s/is_mongos.h"
 
 namespace mongo {
 namespace {
 
-bool isClusterNode() {
-    return serverGlobalParams.clusterRole != ClusterRole::None;
-}
-
 class ShardingServerStatus final : public ServerStatusSection {
 public:
     ShardingServerStatus() : ServerStatusSection("sharding") {}
diff --git a/src/mongo/s/SConscript b/src/mongo/s/SConscript
index 4def356d037..59a989bd478 100644
--- a/src/mongo/s/SConscript
+++ b/src/mongo/s/SConscript
@@ -351,7 +351,9 @@ env.Library(
     source=[
         'is_mongos.cpp',
     ],
-    LIBDEPS=[],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/db/server_options_core',
+    ],
 )
 
 env.CppUnitTest(
diff --git a/src/mongo/s/catalog_cache.cpp b/src/mongo/s/catalog_cache.cpp
index e9ae91e094d..1cc594cdb83 100644
--- a/src/mongo/s/catalog_cache.cpp
+++ b/src/mongo/s/catalog_cache.cpp
@@ -274,6 +274,17 @@ void CatalogCache::invalidateShardedCollection(const NamespaceString& nss) {
     it->second->collections[nss.ns()].needsRefresh = true;
 }
 
+void CatalogCache::purgeCollection(const NamespaceString& nss) {
+    stdx::lock_guard<stdx::mutex> lg(_mutex);
+
+    auto itDb = _databases.find(nss.db());
+    if (itDb == _databases.end()) {
+        return;
+    }
+
+    itDb->second->collections.erase(nss.ns());
+}
+
 void CatalogCache::purgeDatabase(StringData dbName) {
     stdx::lock_guard<stdx::mutex> lg(_mutex);
     _databases.erase(dbName);
diff --git a/src/mongo/s/catalog_cache.h b/src/mongo/s/catalog_cache.h
index f64ceff1e0e..19c3f0eb43b 100644
--- a/src/mongo/s/catalog_cache.h
+++ b/src/mongo/s/catalog_cache.h
@@ -111,6 +111,12 @@ public:
     void invalidateShardedCollection(const NamespaceString& nss);
 
     /**
+     * Non-blocking method, which removes the entire specified collection from the cache (resulting
+     * in full refresh on subsequent access)
+     */
+    void purgeCollection(const NamespaceString& nss);
+
+    /**
      * Non-blocking method, which removes the entire specified database (including its collections)
      * from the cache.
      */
diff --git a/src/mongo/s/commands/SConscript b/src/mongo/s/commands/SConscript
index 23fe7a7a7d6..d080e2fe098 100644
--- a/src/mongo/s/commands/SConscript
+++ b/src/mongo/s/commands/SConscript
@@ -9,7 +9,8 @@ env.Library(
     target='shared_cluster_commands',
     source=[
         'cluster_commands_helpers.cpp',
-        'cluster_get_shard_map_cmd.cpp',
+        'flush_router_config_cmd.cpp',
+        'get_shard_map_cmd.cpp',
     ],
     LIBDEPS=[
         '$BUILD_DIR/mongo/db/commands',
@@ -42,7 +43,6 @@ env.Library(
         'cluster_explain_cmd.cpp',
         'cluster_find_and_modify_cmd.cpp',
         'cluster_find_cmd.cpp',
-        'cluster_flush_router_config_cmd.cpp',
         'cluster_fsync_cmd.cpp',
         'cluster_ftdc_commands.cpp',
         'cluster_get_last_error_cmd.cpp',
diff --git a/src/mongo/s/commands/cluster_flush_router_config_cmd.cpp b/src/mongo/s/commands/flush_router_config_cmd.cpp
index 6caea4afe56..a8553e0e555 100644
--- a/src/mongo/s/commands/cluster_flush_router_config_cmd.cpp
+++ b/src/mongo/s/commands/flush_router_config_cmd.cpp
@@ -28,11 +28,14 @@
  *    it in the license file.
  */
 
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kSharding
+
 #include "mongo/platform/basic.h"
 
 #include "mongo/db/commands.h"
-#include "mongo/s/catalog_cache.h"
 #include "mongo/s/grid.h"
+#include "mongo/s/is_mongos.h"
+#include "mongo/util/log.h"
 
 namespace mongo {
 namespace {
@@ -45,32 +48,58 @@ public:
         return true;
     }
 
-    virtual bool adminOnly() const {
+    bool adminOnly() const override {
         return true;
     }
 
-
-    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+    bool supportsWriteConcern(const BSONObj& cmd) const override {
         return false;
     }
 
-    virtual void help(std::stringstream& help) const {
-        help << "flush all router config";
+    void help(std::stringstream& help) const override {
+        help << "Flushes the cached routing information for a single collection, entire database "
+                "(and its collections) or all databases, which would cause full reload from the "
+                "config server on the next access.\n"
+                "Usage:\n"
+                "{flushRouterConfig: 1} flushes all databases\n"
+                "{flushRouterConfig: 'db'} flushes only the given database (and its collections)\n"
+                "{flushRouterconfig: 'db.coll'} flushes only the given collection";
     }
 
-    virtual void addRequiredPrivileges(const std::string& dbname,
-                                       const BSONObj& cmdObj,
-                                       std::vector<Privilege>* out) {
+    void addRequiredPrivileges(const std::string& dbname,
+                               const BSONObj& cmdObj,
+                               std::vector<Privilege>* out) override {
         ActionSet actions;
         actions.addAction(ActionType::flushRouterConfig);
         out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
     }
 
-    virtual bool run(OperationContext* opCtx,
-                     const std::string& dbname,
-                     const BSONObj& cmdObj,
-                     BSONObjBuilder& result) {
-        Grid::get(opCtx)->catalogCache()->purgeAllDatabases();
+    bool run(OperationContext* opCtx,
+             const std::string& dbname,
+             const BSONObj& cmdObj,
+             BSONObjBuilder& result) override {
+        auto const grid = Grid::get(opCtx);
+        uassert(ErrorCodes::ShardingStateNotInitialized,
+                "Sharding is not enabled",
+                grid->isShardingInitialized());
+
+        auto const catalogCache = grid->catalogCache();
+
+        const auto argumentElem = cmdObj.firstElement();
+        if (argumentElem.isNumber() || argumentElem.isBoolean()) {
+            LOG(0) << "Routing metadata flushed for all databases";
+            catalogCache->purgeAllDatabases();
+        } else {
+            const auto ns = argumentElem.checkAndGetStringData();
+            if (nsIsDbOnly(ns)) {
+                LOG(0) << "Routing metadata flushed for database " << ns;
+                catalogCache->purgeDatabase(ns);
+            } else {
+                const NamespaceString nss(ns);
+                LOG(0) << "Routing metadata flushed for collection " << nss;
+                catalogCache->purgeCollection(nss);
+            }
+        }
 
         result.appendBool("flushed", true);
         return true;
diff --git a/src/mongo/s/commands/cluster_get_shard_map_cmd.cpp b/src/mongo/s/commands/get_shard_map_cmd.cpp
index c823a081a90..c823a081a90 100644
--- a/src/mongo/s/commands/cluster_get_shard_map_cmd.cpp
+++ b/src/mongo/s/commands/get_shard_map_cmd.cpp
diff --git a/src/mongo/s/grid.h b/src/mongo/s/grid.h
index 32dbc76777f..7df58106677 100644
--- a/src/mongo/s/grid.h
+++ b/src/mongo/s/grid.h
@@ -31,6 +31,9 @@
 #pragma once
 
 #include "mongo/db/repl/optime.h"
+#include "mongo/s/catalog/sharding_catalog_client.h"
+#include "mongo/s/catalog_cache.h"
+#include "mongo/s/client/shard_registry.h"
 #include "mongo/stdx/functional.h"
 #include "mongo/stdx/memory.h"
 #include "mongo/stdx/mutex.h"
@@ -38,12 +41,9 @@
 namespace mongo {
 
 class BalancerConfiguration;
-class CatalogCache;
-class ShardingCatalogClient;
 class ClusterCursorManager;
 class OperationContext;
 class ServiceContext;
-class ShardRegistry;
 
 namespace executor {
 struct ConnectionPoolStats;
@@ -52,8 +52,7 @@ class TaskExecutorPool;
 }  // namespace executor
 
 /**
- * Holds the global sharding context. Single instance exists for a running server. Exists on
- * both MongoD and MongoS.
+ * Contains the sharding context for a running server. Exists on both MongoD and MongoS.
  */
 class Grid {
 public:
diff --git a/src/mongo/s/is_mongos.cpp b/src/mongo/s/is_mongos.cpp
index 2a4ebb2f53e..1855e475081 100644
--- a/src/mongo/s/is_mongos.cpp
+++ b/src/mongo/s/is_mongos.cpp
@@ -28,18 +28,31 @@
  *    it in the license file.
  */
 
+#include "mongo/platform/basic.h"
+
 #include "mongo/s/is_mongos.h"
 
+#include "mongo/db/server_options.h"
+
 namespace mongo {
 namespace {
 bool mongosState = false;
 }  // namespace
-}  // namespace mongo
 
-bool mongo::isMongos() {
+bool isMongos() {
     return mongosState;
 }
 
-void mongo::setMongos(const bool state) {
+void setMongos(const bool state) {
     mongosState = state;
 }
+
+bool isClusterNode() {
+    return serverGlobalParams.clusterRole != ClusterRole::None;
+}
+
+bool isClusterNodeOrRouter() {
+    return isClusterNode() || isMongos();
+}
+
+}  // namespace mongo
diff --git a/src/mongo/s/is_mongos.h b/src/mongo/s/is_mongos.h
index 2567f7ba6d9..90184105c8f 100644
--- a/src/mongo/s/is_mongos.h
+++ b/src/mongo/s/is_mongos.h
@@ -31,9 +31,25 @@
 #pragma once
 
 namespace mongo {
-/** Returns true when the running process is `mongos` and false otherwise. */
+
+/**
+ * Returns true when the running process is `mongos` and false otherwise.
+ */
 bool isMongos();
 
-/** Set the global state flag indicating whether the running process is `mongos` or not. */
+/**
+ * Set the global state flag indicating whether the running process is `mongos` or not.
+ */
 void setMongos(const bool state = true);
+
+/**
+ * Returns whether this node is config server or a shard.
+ */
+bool isClusterNode();
+
+/**
+ * Returns whether this node is config server, shard or mongos.
+ */
+bool isClusterNodeOrRouter();
+
 }  // namespace mongo