WL#15440 MySQL REST Service (MRS) - Umbrella WL

Bug#37526847 Changing [mysql_rest_service].router_id in the config file has no effect.

When Router detects that there is the same Router registered but with
different router_id it fails to start.

Change-Id: Ib2e9c1794e7da18e8efb0d4fe057e76b54bf75a7

Author: Tomasz Stepniak

router/src/mysql_rest_service/include/mrs/database/query_router_info.h

@@ -0,0 +1,50 @@
+/*
+  Copyright (c) 2025, Oracle and/or its affiliates.
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License, version 2.0,
+  as published by the Free Software Foundation.
+
+  This program is also distributed with certain software (including
+  but not limited to OpenSSL) that is licensed under separate terms,
+  as designated in a particular file or component or in included license
+  documentation.  The authors of MySQL hereby grant you an additional
+  permission to link the program and your derivative works with the
+  separately licensed software that they have included with MySQL.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef ROUTER_SRC_REST_MRS_SRC_MRS_DATABASE_QUERY_ROUTER_INFO_H_
+#define ROUTER_SRC_REST_MRS_SRC_MRS_DATABASE_QUERY_ROUTER_INFO_H_
+
+#include "mrs/database/helper/query.h"
+
+#include <string>
+
+namespace mrs {
+namespace database {
+
+class QueryRouterInfo : private Query {
+ public:
+  std::optional<uint64_t> find_existing_router_instances(
+      MySQLSession *session, const std::string &router_name,
+      const std::string &address);
+
+ private:
+  void on_row(const ResultRow &r) override;
+
+  std::optional<uint64_t> id_;
+};
+
+}  // namespace database
+}  // namespace mrs
+
+#endif  // ROUTER_SRC_REST_MRS_SRC_MRS_DATABASE_QUERY_ROUTER_INFO_H_

router/src/mysql_rest_service/src/CMakeLists.txt

@@ -106,6 +106,7 @@ ADD_STATIC_LIBRARY(mysql_rest_service_db
   mrs/database/query_rest_task.cc
   mrs/database/query_rest_task_status.cc
   mrs/database/query_rest_table_updater.cc
+  mrs/database/query_router_info.cc
   mrs/database/query_state.cc
   mrs/database/query_statistics.cc
   mrs/database/query_version.cc

router/src/mysql_rest_service/src/mrs/database/query_router_info.cc

@@ -0,0 +1,67 @@
+/*
+  Copyright (c) 2025, Oracle and/or its affiliates.
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License, version 2.0,
+  as published by the Free Software Foundation.
+
+  This program is also distributed with certain software (including
+  but not limited to OpenSSL) that is licensed under separate terms,
+  as designated in a particular file or component or in included license
+  documentation.  The authors of MySQL hereby grant you an additional
+  permission to link the program and your derivative works with the
+  separately licensed software that they have included with MySQL.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include <stdexcept>
+
+#include "mrs/database/query_router_info.h"
+
+#include "mysqld_error.h"
+
+namespace mrs {
+namespace database {
+
+std::optional<uint64_t> QueryRouterInfo::find_existing_router_instances(
+    MySQLSession *session, const std::string &router_name,
+    const std::string &address) {
+  try {
+    mysqlrouter::sqlstring sql_query{
+        "SELECT `id` FROM mysql_rest_service_metadata.router WHERE"
+        " router_name = ? AND address = ?"};
+    sql_query << router_name << address;
+    query(session, sql_query);
+  } catch (const mysqlrouter::MySQLSession::Error &error) {
+    if (error.code() != ER_NO_SUCH_TABLE &&
+        error.code() != ER_TABLEACCESS_DENIED_ERROR) {
+      throw;
+    }
+  }
+  return id_;
+}
+
+void QueryRouterInfo::on_row(const ResultRow &r) {
+  if (r.size() != 1) {
+    throw std::runtime_error(
+        "Could not fetch router information from "
+        "`mysql_rest_service_metadata`.`router`");
+  }
+
+  try {
+    id_ = std::stoi(r[0]);
+  } catch (const std::exception &) {
+    id_ = std::nullopt;
+  }
+}
+
+}  // namespace database
+}  // namespace mrs

router/src/mysql_rest_service/src/mysql_rest_service_plugin.cc

@@ -36,6 +36,7 @@
 #include "my_sys.h"
 #include "my_thread.h"     // NOLINT(build/include_subdir)
 #include "mysqld_error.h"  // NOLINT(build/include_subdir)
+#include "socket_operations.h"
 
 #include "keyring/keyring_manager.h"
 #include "mysql/harness/loader.h"
@@ -49,6 +50,7 @@
 #include "helper/task_control.h"
 #include "mrs/authentication/auth_handler_factory.h"
 #include "mrs/database/query_factory_proxy.h"
+#include "mrs/database/query_router_info.h"
 #include "mrs/database/schema_monitor.h"
 #include "mrs/database/slow_query_monitor.h"
 #include "mrs/endpoint/handler/handler_debug.cc"
@@ -85,6 +87,13 @@ void trace_error(const char *variable_user, const char *access,
       variable_user, e.code(), e.message().c_str());
 }
 
+std::optional<uint64_t> find_existing_routers(
+    mysqlrouter::MySQLSession *session, const std::string &router_name,
+    const std::string &address) {
+  mrs::database::QueryRouterInfo q;
+  return q.find_existing_router_instances(session, router_name, address);
+}
+
 }  // namespace
 
 class MrsModule {
@@ -112,8 +121,10 @@ class MrsModule {
     // TODO(areliga): remove that when rebased to the Router version that fixes
     // ODR issues
     my_init();
+    collector::MysqlCacheManager::CachedObject conn1;
+
     try {
-      auto conn1 = mysql_connection_cache.get_instance(
+      conn1 = mysql_connection_cache.get_instance(
           collector::kMySQLConnectionMetadataRO, true);
 
       check_version_compatibility(conn1.get());
@@ -150,6 +161,18 @@ class MrsModule {
           "failed. For more informations look at previous error messages.");
     }
 
+    auto socket_ops = mysql_harness::SocketOperations::instance();
+    const auto name = configuration.router_name_;
+    const auto address = socket_ops->get_local_hostname();
+    const auto existing_id_maybe =
+        find_existing_routers(conn1.get(), name, address);
+    if (existing_id_maybe && *existing_id_maybe != configuration.router_id_) {
+      throw std::runtime_error(
+          "Metadata already contains Router registered as '" + name + "' at '" +
+          address + "' with id: " + std::to_string(*existing_id_maybe) +
+          ", new id: " + std::to_string(configuration.router_id_));
+    }
+
     return true;
   }
 

router/tests/component/data/local_modules/common_statements.js

@@ -130,6 +130,8 @@ var defaults = {
   router_hostname: "router-host",
   router_options: "",
   router_name: "test_router",
+  mrs_router_id: 1,
+  mrs_basedir: "",
 };
 
 function ensure_type(options, field, expected_type) {
@@ -1433,6 +1435,47 @@ function get_response(stmt_key, options) {
           rows: [[options.routing_guidelines]]
         }
       };
+    case "mrs_set_sql_mode":
+      return {"stmt": "SET @@SESSION.sql_mode=DEFAULT;", "ok": {}};
+    case "mrs_set_meta_provider_role":
+      return {"stmt": "SET ROLE mysql_rest_service_meta_provider", "ok": {}};
+    case "mrs_select_version":
+      return {
+        stmt:
+            "SELECT substring_index(@@version, '.', 1), concat(@@version_comment, @@version)",
+        result: {
+          columns: [
+            {
+              "name": "substring_index(@@version, '.', 1)",
+              "type": "VAR_STRING"
+            },
+            {
+              "name": "concat(@@version_comment, @@version)",
+              "type": "VAR_STRING"
+            }
+          ],
+          rows: [["9", "Source distribution mrs"]],
+        }
+      };
+    case "mrs_select_basedir":
+      return {
+        stmt: "SELECT @@basedir",
+        result: {
+          columns: [{"name": "@@basedir", "type": "VAR_STRING"}],
+          rows: [[options.mrs_basedir]],
+        }
+      };
+    case "mrs_set_data_provider_role":
+      return {"stmt": "SET ROLE mysql_rest_service_data_provider", "ok": {}};
+    case "mrs_select_router_id":
+      return {
+        stmt_regex:
+            "SELECT `id` FROM mysql_rest_service_metadata.router WHERE router_name = '.*' AND address = '.*'",
+        result: {
+          columns: [{"name": "id", "type": "LONG"}],
+          rows: [[options.mrs_router_id]],
+        }
+      };
   };
 };
 

router/tests/component/data/metadata_dynamic_nodes_v2_gr_mrs.js

@@ -0,0 +1,135 @@
+var common_stmts = require("common_statements");
+var gr_memberships = require("gr_memberships");
+
+if (mysqld.global.gr_node_host === undefined) {
+  mysqld.global.gr_node_host = "127.0.0.1";
+}
+
+if (mysqld.global.gr_id === undefined) {
+  mysqld.global.gr_id = "uuid";
+}
+
+if (mysqld.global.gr_nodes === undefined) {
+  mysqld.global.gr_nodes = [];
+}
+
+if (mysqld.global.cluster_nodes === undefined) {
+  mysqld.global.cluster_nodes = [];
+}
+
+if (mysqld.global.notices === undefined) {
+  mysqld.global.notices = [];
+}
+
+if (mysqld.global.md_query_count === undefined) {
+  mysqld.global.md_query_count = 0;
+}
+
+if (mysqld.global.transaction_count === undefined) {
+  mysqld.global.transaction_count = 0;
+}
+
+if (mysqld.global.cluster_name === undefined) {
+  mysqld.global.cluster_name = "test";
+}
+
+if (mysqld.global.mrs_router_id === undefined) {
+  mysqld.global.mrs_router_id = 1;
+}
+
+({
+  handshake: {
+    auth: {
+      username: mysqld.global.user,
+      password: mysqld.global.password,
+    },
+    greeting: {server_version: mysqld.global.server_version}
+  },
+  stmts: function(stmt) {
+    // ensure the cluster-type is set even if set_mock_metadata() did not set
+    // it.
+    if (mysqld.global.cluster_type === undefined) {
+      mysqld.global.cluster_type = "gr";
+    }
+
+    var members = gr_memberships.gr_members(
+        mysqld.global.gr_node_host, mysqld.global.gr_nodes);
+
+    var options = {
+      group_replication_members: members,
+      innodb_cluster_instances: gr_memberships.cluster_nodes(
+          mysqld.global.gr_node_host, mysqld.global.cluster_nodes),
+      gr_id: mysqld.global.gr_id,
+      innodb_cluster_name: mysqld.global.cluster_name,
+      mrs_router_id: mysqld.global.mrs_router_id,
+    };
+
+    // prepare the responses for common statements
+    var common_responses = common_stmts.prepare_statement_responses(
+        [
+          "router_set_session_options",
+          "router_set_gr_consistency_level",
+          "router_select_cluster_type_v2",
+          "select_port",
+          "router_commit",
+          "router_rollback",
+          "router_select_schema_version",
+          "router_check_member_state",
+          "router_select_members_count",
+          "router_select_group_membership",
+          "router_clusterset_present",
+          "router_select_router_options_view",
+          "get_routing_guidelines_version",
+          "get_guidelines_router_info",
+          "get_routing_guidelines",
+          "mrs_set_sql_mode",
+          "mrs_set_meta_provider_role",
+          "mrs_select_version",
+          "mrs_select_basedir",
+          "mrs_set_data_provider_role",
+
+
+        ],
+        options);
+
+    var common_responses_regex = common_stmts.prepare_statement_responses_regex(
+        [
+          "mrs_select_router_id",
+        ],
+        options);
+
+    var router_select_metadata =
+        common_stmts.get("router_select_metadata_v2_gr", options);
+
+    var router_start_transaction =
+        common_stmts.get("router_start_transaction", options);
+
+
+    if (common_responses.hasOwnProperty(stmt)) {
+      return common_responses[stmt];
+    } else if (
+        (res = common_stmts.handle_regex_stmt(stmt, common_responses_regex)) !==
+        undefined) {
+      return res;
+    } else if (stmt === "SELECT aurora_version()") {
+      return {
+        error: {
+          code: 1046,
+          sql_state: "HY001",
+          message: "No database selected",
+        }
+      };
+    } else if (stmt === router_start_transaction.stmt) {
+      mysqld.global.transaction_count++;
+      return router_start_transaction;
+    } else if (stmt === router_select_metadata.stmt) {
+      mysqld.global.md_query_count++;
+      return router_select_metadata;
+    } else {
+      return common_stmts.unknown_statement_response(stmt);
+    }
+  },
+  notices: (function() {
+    return mysqld.global.notices;
+  })()
+})