feat: Added SELECT redis command

redis/include/userver/storages/redis/impl/base.hpp

@@ -27,16 +27,19 @@ struct ConnectionInfo {
   bool read_only = false;
   ConnectionSecurity connection_security = ConnectionSecurity::kNone;
   using HostVector = std::vector<std::string>;
+  size_t database_index = 0;
 
   ConnectionInfo() = default;
   ConnectionInfo(std::string host, int port, Password password,
                  bool read_only = false,
-                 ConnectionSecurity security = ConnectionSecurity::kNone)
+                 ConnectionSecurity security = ConnectionSecurity::kNone,
+                 size_t database_index = {})
       : host{std::move(host)},
         port{port},
         password{std::move(password)},
         read_only{read_only},
-        connection_security(security) {}
+        connection_security(security),
+        database_index{database_index} {}
 };
 
 struct Stat {

redis/include/userver/storages/redis/impl/secdist_redis.hpp

@@ -21,6 +21,7 @@ struct RedisSettings {
 
   std::vector<std::string> shards;
   std::vector<HostPort> sentinels;
+  size_t database_index{0};
   redis::Password password{std::string()};
   redis::ConnectionSecurity secure_connection{redis::ConnectionSecurity::kNone};
 };

redis/src/storages/redis/impl/redis.cpp

@@ -28,6 +28,7 @@
 #include <storages/redis/impl/redis_stats.hpp>
 #include <storages/redis/impl/tcp_socket.hpp>
 #include <userver/storages/redis/impl/reply.hpp>
+#include <userver/utils/scope_guard.hpp>
 
 #include "command_control_impl.hpp"
 
@@ -146,7 +147,7 @@ class Redis::RedisImpl : public std::enable_shared_from_this<Redis::RedisImpl> {
   ~RedisImpl();
 
   void Connect(const ConnectionInfo::HostVector& host_addrs, int port,
-               const Password& password);
+               const Password& password, size_t database_index);
   void Disconnect();
 
   bool AsyncCommand(const CommandPtr& command);
@@ -233,6 +234,7 @@ class Redis::RedisImpl : public std::enable_shared_from_this<Redis::RedisImpl> {
   void ProcessCommand(const CommandPtr& command);
 
   void Authenticate();
+  void SelectDatabase();
   void SendReadOnly();
   void FreeCommands();
 
@@ -251,7 +253,8 @@ class Redis::RedisImpl : public std::enable_shared_from_this<Redis::RedisImpl> {
   static bool WatchCommandTimerEnabled(
       const CommandsBufferingSettings& commands_buffering_settings);
 
-  bool Connect(const std::string& host, int port, const Password& password);
+  bool Connect(const std::string& host, int port, const Password& password,
+               size_t database_index);
 
   Redis* redis_obj_;
   engine::ev::ThreadControl ev_thread_control_;
@@ -272,6 +275,7 @@ class Redis::RedisImpl : public std::enable_shared_from_this<Redis::RedisImpl> {
   uint16_t port_ = 0;
   std::string server_;
   Password password_{std::string()};
+  std::size_t database_index_ = 0;
   std::atomic<size_t> commands_size_ = 0;
   size_t sent_count_ = 0;
   size_t cmd_counter_ = 0;
@@ -336,8 +340,9 @@ Redis::~Redis() {
 }
 
 void Redis::Connect(const ConnectionInfo::HostVector& host_addrs, int port,
-                    const Password& password) {
-  impl_->Connect(host_addrs, port, password);
+                    const Password& password,
+                    size_t database_index) {
+  impl_->Connect(host_addrs, port, password, database_index);
 }
 
 bool Redis::AsyncCommand(const CommandPtr& command) {
@@ -445,17 +450,19 @@ void Redis::RedisImpl::Detach() {
 }
 
 void Redis::RedisImpl::Connect(const ConnectionInfo::HostVector& host_addrs,
-                               int port, const Password& password) {
+                               int port, const Password& password,
+                               size_t database_index) {
   for (const auto& host : host_addrs)
-    if (Connect(host, port, password)) return;
+    if (Connect(host, port, password, database_index)) return;
 
   LOG_ERROR() << "error async connect to Redis server (host addrs ="
               << host_addrs << ", port=" << port << ")";
   SetState(State::kInitError);
 }
 
 bool Redis::RedisImpl::Connect(const std::string& host, int port,
-                               const Password& password) {
+                               const Password& password,
+                               size_t database_index) {
   UASSERT(context_ == nullptr);
   UASSERT(state_ == State::kInit);
 
@@ -466,6 +473,7 @@ bool Redis::RedisImpl::Connect(const std::string& host, int port,
   log_extra_.Extend("redis_server", GetServer());
   log_extra_.Extend("server_id", GetServerId().GetId());
   password_ = password;
+  database_index_ = database_index;
   LOG_INFO() << log_extra_ << "Async connect to Redis server=" << GetServer();
   context_ = redisAsyncConnect(host.c_str(), port);
 
@@ -1040,19 +1048,13 @@ bool Redis::RedisImpl::InitSecureConnection() {
 
 void Redis::RedisImpl::Authenticate() {
   if (password_.GetUnderlying().empty()) {
-    if (send_readonly_)
-      SendReadOnly();
-    else
-      SetState(State::kConnected);
+    SendReadOnly();
   } else {
     ProcessCommand(PrepareCommand(
         CmdArgs{"AUTH", password_.GetUnderlying()},
         [this](const CommandPtr&, ReplyPtr reply) {
           if (*reply && reply->data.IsStatus()) {
-            if (send_readonly_)
-              SendReadOnly();
-            else
-              SetState(State::kConnected);
+            SendReadOnly();
           } else {
             if (*reply) {
               if (reply->IsUnknownCommandError()) {
@@ -1079,12 +1081,17 @@ void Redis::RedisImpl::Authenticate() {
 }
 
 void Redis::RedisImpl::SendReadOnly() {
+  if (!send_readonly_) {
+    SelectDatabase();
+    return;
+  }
+
   LOG_DEBUG() << "Send READONLY command to slave "
               << GetServerId().GetDescription() << " in cluster mode";
   ProcessCommand(PrepareCommand(CmdArgs{"READONLY"}, [this](const CommandPtr&,
                                                             ReplyPtr reply) {
     if (*reply && reply->data.IsStatus()) {
-      SetState(State::kConnected);
+      SelectDatabase();
     } else {
       if (*reply) {
         LOG_LIMITED_ERROR()
@@ -1101,6 +1108,49 @@ void Redis::RedisImpl::SendReadOnly() {
   }));
 }
 
+void Redis::RedisImpl::SelectDatabase() {
+  // To get rid of the redundant `SELECT 0` command
+  // since 0 is the default database index, and it will be set automatically
+  if (database_index_ == 0) {
+    SetState(RedisState::kConnected);
+    return;
+  }
+
+  ProcessCommand(PrepareCommand(
+      CmdArgs{"SELECT", database_index_},
+      [this](const CommandPtr&, ReplyPtr reply) {
+        if (*reply && reply->data.IsStatus()) {
+          SetState(RedisState::kConnected);
+          LOG_INFO() << log_extra_
+                     << "Selected redis logical database with index "
+                     << database_index_;
+          return;
+        }
+
+        const utils::ScopeGuard auto_disconnect([this]() { Disconnect(); });
+
+        if (!*reply) {
+          LOG_LIMITED_ERROR()
+              << "SELECT failed with status " << reply->status << " ("
+              << reply->status_string << ") " << log_extra_;
+          return;
+        }
+
+        if (reply->IsUnknownCommandError()) {
+          LOG_WARNING() << log_extra_
+                        << "SELECT failed: unknown command `SELECT` - "
+                           "possible when connecting to Sentinel instead "
+                           "of Redis master or slave instance";
+          return;
+        }
+
+        LOG_LIMITED_ERROR()
+            << log_extra_
+            << "SELECT failed: response type=" << reply->data.GetTypeString()
+            << " msg=" << reply->data.ToDebugString();
+      }));
+}
+
 void Redis::RedisImpl::OnRedisReply(redisAsyncContext* c, void* r,
                                     void* privdata) noexcept {
   auto* impl = static_cast<Redis::RedisImpl*>(c->data);

redis/src/storages/redis/impl/redis.hpp

@@ -33,7 +33,8 @@ class Redis {
   Redis(Redis&& o) = delete;
 
   void Connect(const ConnectionInfo::HostVector& host_addrs, int port,
-               const Password& password);
+               const Password& password,
+               size_t database_index = 0);
 
   bool AsyncCommand(const CommandPtr& command);
   size_t GetRunningCommands() const;

redis/src/storages/redis/impl/redis_stats.cpp

@@ -76,6 +76,7 @@ const std::string_view kCommandTypes[] = {
     "scan",
     "scard",
     "script",
+    "select",
     "sentinel",
     "set",
     "setex",

redis/src/storages/redis/impl/sentinel.cpp

@@ -63,15 +63,18 @@ void OnSubscribeImpl(std::string_view message_type,
 
 }  // namespace
 
-Sentinel::Sentinel(
-    const std::shared_ptr<ThreadPools>& thread_pools,
-    const std::vector<std::string>& shards,
-    const std::vector<ConnectionInfo>& conns, std::string shard_group_name,
-    const std::string& client_name, const Password& password,
-    ConnectionSecurity connection_security, ReadyChangeCallback ready_callback,
-    dynamic_config::Source dynamic_config_source,
-    std::unique_ptr<KeyShard>&& key_shard, CommandControl command_control,
-    const testsuite::RedisControl& testsuite_redis_control, ConnectionMode mode)
+Sentinel::Sentinel(const std::shared_ptr<ThreadPools>& thread_pools,
+                   const std::vector<std::string>& shards,
+                   const std::vector<ConnectionInfo>& conns,
+                   std::string shard_group_name, const std::string& client_name,
+                   const Password& password,
+                   ConnectionSecurity connection_security,
+                   ReadyChangeCallback ready_callback,
+                   dynamic_config::Source dynamic_config_source,
+                   std::unique_ptr<KeyShard>&& key_shard,
+                   CommandControl command_control,
+                   const testsuite::RedisControl& testsuite_redis_control,
+                   ConnectionMode mode, size_t database_index)
     : thread_pools_(thread_pools),
       secdist_default_command_control_(command_control),
       testsuite_redis_control_(testsuite_redis_control) {
@@ -96,7 +99,7 @@ Sentinel::Sentinel(
           *sentinel_thread_control_, thread_pools_->GetRedisThreadPool(), *this,
           shards, conns, std::move(shard_group_name), client_name, password,
           connection_security, std::move(ready_callback), std::move(key_shard),
-          dynamic_config_source, mode);
+          dynamic_config_source, mode, database_index);
     }
   });
 }
@@ -176,7 +179,8 @@ std::shared_ptr<Sentinel> Sentinel::CreateSentinel(
         thread_pools, shards, conns, std::move(shard_group_name), client_name,
         password, settings.secure_connection, std::move(ready_callback),
         dynamic_config_source, std::move(key_shard), command_control,
-        testsuite_redis_control);
+        testsuite_redis_control, ConnectionMode::kCommands,
+        settings.database_index);
     client->Start();
   }
 

redis/src/storages/redis/impl/sentinel.hpp

@@ -71,7 +71,8 @@ class Sentinel {
            std::unique_ptr<KeyShard>&& key_shard = nullptr,
            CommandControl command_control = {},
            const testsuite::RedisControl& testsuite_redis_control = {},
-           ConnectionMode mode = ConnectionMode::kCommands);
+           ConnectionMode mode = ConnectionMode::kCommands,
+           size_t database_index = 0);
   virtual ~Sentinel();
 
   void Start();

redis/src/storages/redis/impl/sentinel_impl.cpp

@@ -64,7 +64,8 @@ SentinelImpl::SentinelImpl(
     const std::string& client_name, const Password& password,
     ConnectionSecurity connection_security, ReadyChangeCallback ready_callback,
     std::unique_ptr<KeyShard>&& key_shard,
-    dynamic_config::Source dynamic_config_source, ConnectionMode mode)
+    dynamic_config::Source dynamic_config_source, ConnectionMode mode,
+    size_t database_index)
     : sentinel_obj_(sentinel),
       ev_thread_(sentinel_thread_control),
       shard_group_name_(std::move(shard_group_name)),
@@ -79,7 +80,8 @@ SentinelImpl::SentinelImpl(
       key_shard_(std::move(key_shard)),
       connection_mode_(mode),
       slot_info_(IsInClusterMode() ? std::make_unique<SlotInfo>() : nullptr),
-      dynamic_config_source_(dynamic_config_source) {
+      dynamic_config_source_(dynamic_config_source),
+      database_index_(database_index) {
   for (size_t i = 0; i < init_shards_->size(); ++i) {
     shards_[(*init_shards_)[i]] = i;
     connected_statuses_.push_back(std::make_unique<ConnectedStatus>());
@@ -637,6 +639,7 @@ void SentinelImpl::ReadSentinels() {
         for (auto shard_conn : info) {
           if (shards_.find(shard_conn.Name()) != shards_.end()) {
             shard_conn.SetConnectionSecurity(connection_security_);
+            shard_conn.SetDatabaseIndex(database_index_);
             shard_found[shards_[shard_conn.Name()]] = true;
             watcher->host_port_to_shard[shard_conn.HostPort()] =
                 shards_[shard_conn.Name()];
@@ -675,6 +678,7 @@ void SentinelImpl::ReadSentinels() {
                   shard_conn.SetName(shard);
                   shard_conn.SetReadOnly(true);
                   shard_conn.SetConnectionSecurity(connection_security_);
+                  shard_conn.SetDatabaseIndex(database_index_);
                   if (shards_.find(shard_conn.Name()) != shards_.end())
                     watcher->host_port_to_shard[shard_conn.HostPort()] =
                         shards_[shard_conn.Name()];

redis/src/storages/redis/impl/sentinel_impl.hpp

@@ -112,7 +112,8 @@ class SentinelImpl : public SentinelImplBase {
                ReadyChangeCallback ready_callback,
                std::unique_ptr<KeyShard>&& key_shard,
                dynamic_config::Source dynamic_config_source,
-               ConnectionMode mode = ConnectionMode::kCommands);
+               ConnectionMode mode = ConnectionMode::kCommands,
+               size_t database_index = 0);
   ~SentinelImpl() override;
 
   std::unordered_map<ServerId, size_t, ServerIdHasher>
@@ -285,6 +286,7 @@ class SentinelImpl : public SentinelImplBase {
   std::optional<CommandsBufferingSettings> commands_buffering_settings_;
   dynamic_config::Source dynamic_config_source_;
   std::atomic<int> publish_shard_{0};
+  std::size_t database_index_{0};
 };
 
 }  // namespace redis