@ -8,7 +8,9 @@ using json = nlohmann::json;
# define PROXYJSON
# include "Query_Tool_Handler.h"
# include "MCP_Thread.h"
# include "proxysql_debug.h"
# include "proxysql_admin.h"
# include "Static_Harvester.h"
# include <vector>
@ -18,6 +20,9 @@ using json = nlohmann::json;
// MySQL client library
# include <mysql.h>
# include <libpq-fe.h>
extern ProxySQL_Admin * GloAdmin ;
// ============================================================
// JSON Helper Functions
@ -203,6 +208,7 @@ Query_Tool_Handler::Query_Tool_Handler(
: catalog ( NULL ) ,
harvester ( NULL ) ,
pool_size ( 0 ) ,
pg_pool_size ( 0 ) ,
max_rows ( 200 ) ,
timeout_ms ( 2000 ) ,
allow_select_star ( false )
@ -302,58 +308,42 @@ void Query_Tool_Handler::close() {
connection_pool . clear ( ) ;
pool_size = 0 ;
pthread_mutex_unlock ( & pool_lock ) ;
}
int Query_Tool_Handler : : init_connection_pool ( ) {
// Parse hosts
std : : vector < std : : string > host_list ;
std : : istringstream h ( mysql_hosts ) ;
std : : string host ;
while ( std : : getline ( h , host , ' , ' ) ) {
host . erase ( 0 , host . find_first_not_of ( " \t " ) ) ;
host . erase ( host . find_last_not_of ( " \t " ) + 1 ) ;
if ( ! host . empty ( ) ) {
host_list . push_back ( host ) ;
for ( auto & conn : pgsql_connection_pool ) {
if ( conn . pgconn ) {
PQfinish ( static_cast < PGconn * > ( conn . pgconn ) ) ;
conn . pgconn = NULL ;
}
}
pgsql_connection_pool . clear ( ) ;
pg_pool_size = 0 ;
// Parse ports
std : : vector < int > port_list ;
std : : istringstream p ( mysql_ports ) ;
std : : string port ;
while ( std : : getline ( p , port , ' , ' ) ) {
port . erase ( 0 , port . find_first_not_of ( " \t " ) ) ;
port . erase ( port . find_last_not_of ( " \t " ) + 1 ) ;
if ( ! port . empty ( ) ) {
port_list . push_back ( atoi ( port . c_str ( ) ) ) ;
}
}
// Ensure ports array matches hosts array size
while ( port_list . size ( ) < host_list . size ( ) ) {
port_list . push_back ( 3306 ) ;
}
pthread_mutex_unlock ( & pool_lock ) ;
}
if ( host_list . empty ( ) ) {
proxy_error ( " Query_Tool_Handler: No hosts configured \n " ) ;
return - 1 ;
}
int Query_Tool_Handler : : init_connection_pool ( ) {
refresh_target_registry ( ) ;
pthread_mutex_lock ( & pool_lock ) ;
pool_size = 0 ;
pg_pool_size = 0 ;
for ( size_t i = 0 ; i < host_list . size ( ) ; i + + ) {
for ( const auto & target : target_registry ) {
if ( ! target . executable | | target . protocol ! = " mysql " ) {
continue ;
}
MySQLConnection conn ;
conn . host = host_list [ i ] ;
conn . port = port_list [ i ] ;
conn . target_id = target . target_id ;
conn . auth_profile_id = target . auth_profile_id ;
conn . host = target . host ;
conn . port = target . port ;
conn . in_use = false ;
conn . current_schema = target . default_schema ;
MYSQL * mysql = mysql_init ( NULL ) ;
if ( ! mysql ) {
proxy_error ( " Query_Tool_Handler: mysql_init failed for %s:%d \n " ,
conn . host . c_str ( ) , conn . port ) ;
pthread_mutex_unlock ( & pool_lock ) ;
return - 1 ;
continue ;
}
unsigned int timeout = 5 ;
@ -364,9 +354,9 @@ int Query_Tool_Handler::init_connection_pool() {
if ( ! mysql_real_connect (
mysql ,
conn . host . c_str ( ) ,
mysql_user . c_str ( ) ,
mysql _password. c_str ( ) ,
mysql_schema. empty ( ) ? NULL : mysql _schema. c_str ( ) ,
target. db_username . c_str ( ) ,
target. db _password. c_str ( ) ,
target. default_schema . empty ( ) ? NULL : target . default _schema. c_str ( ) ,
conn . port ,
NULL ,
CLIENT_MULTI_STATEMENTS
@ -374,28 +364,222 @@ int Query_Tool_Handler::init_connection_pool() {
proxy_error ( " Query_Tool_Handler: mysql_real_connect failed for %s:%d: %s \n " ,
conn . host . c_str ( ) , conn . port , mysql_error ( mysql ) ) ;
mysql_close ( mysql ) ;
pthread_mutex_unlock ( & pool_lock ) ;
return - 1 ;
continue ;
}
conn . mysql = mysql ;
connection_pool . push_back ( conn ) ;
pool_size + + ;
proxy_info ( " Query_Tool_Handler: Connected to %s:%d \n " ,
conn . host . c_str ( ) , conn . port ) ;
proxy_info ( " Query_Tool_Handler: Connected target '%s' to %s:%d \n " ,
conn . target_id . c_str ( ) , conn . host . c_str ( ) , conn . port ) ;
if ( default_target_id . empty ( ) ) {
default_target_id = conn . target_id ;
}
}
for ( const auto & target : target_registry ) {
if ( ! target . executable | | target . protocol ! = " pgsql " ) {
continue ;
}
PgSQLConnection conn ;
conn . target_id = target . target_id ;
conn . auth_profile_id = target . auth_profile_id ;
conn . host = target . host ;
conn . port = target . port ;
conn . in_use = false ;
conn . current_schema = target . default_schema ;
std : : ostringstream conninfo ;
conninfo < < " host= " < < conn . host
< < " port= " < < conn . port
< < " user= " < < target . db_username
< < " password= " < < target . db_password
< < " connect_timeout=5 " ;
if ( ! target . default_schema . empty ( ) ) {
conninfo < < " dbname= " < < target . default_schema ;
}
PGconn * pgconn = PQconnectdb ( conninfo . str ( ) . c_str ( ) ) ;
if ( pgconn = = NULL | | PQstatus ( pgconn ) ! = CONNECTION_OK ) {
proxy_error (
" Query_Tool_Handler: PQconnectdb failed for %s:%d: %s \n " ,
conn . host . c_str ( ) , conn . port , pgconn ? PQerrorMessage ( pgconn ) : " null connection "
) ;
if ( pgconn ) {
PQfinish ( pgconn ) ;
}
continue ;
}
conn . pgconn = pgconn ;
pgsql_connection_pool . push_back ( conn ) ;
pg_pool_size + + ;
proxy_info ( " Query_Tool_Handler: Connected target '%s' to pgsql %s:%d \n " ,
conn . target_id . c_str ( ) , conn . host . c_str ( ) , conn . port ) ;
if ( default_target_id . empty ( ) ) {
default_target_id = conn . target_id ;
}
}
pthread_mutex_unlock ( & pool_lock ) ;
proxy_info ( " Query_Tool_Handler: Connection pool initialized with %d connection(s) \n " , pool_size ) ;
if ( ( pool_size + pg_pool_size ) = = 0 ) {
proxy_error ( " Query_Tool_Handler: No executable targets available \n " ) ;
return - 1 ;
}
proxy_info (
" Query_Tool_Handler: Connection pools initialized mysql=%d pgsql=%d, default target '%s' \n " ,
pool_size , pg_pool_size , default_target_id . c_str ( )
) ;
return 0 ;
}
void * Query_Tool_Handler : : get_connection ( ) {
void Query_Tool_Handler : : refresh_target_registry ( ) {
target_registry . clear ( ) ;
default_target_id . clear ( ) ;
if ( ! GloMCPH ) {
return ;
}
// Refresh MCP target/auth map from runtime profile tables before resolving targets.
if ( GloAdmin & & GloAdmin - > admindb ) {
char * error = NULL ;
int cols = 0 ;
int affected_rows = 0 ;
SQLite3_result * resultset = NULL ;
const char * q =
" SELECT t.target_id, t.protocol, t.hostgroup_id, t.auth_profile_id, "
" t.max_rows, t.timeout_ms, t.allow_explain, t.allow_discovery, t.description, "
" a.db_username, a.db_password, a.default_schema "
" FROM runtime_mcp_target_profiles t "
" JOIN runtime_mcp_auth_profiles a ON a.auth_profile_id=t.auth_profile_id "
" WHERE t.active=1 "
" ORDER BY t.target_id " ;
GloAdmin - > admindb - > execute_statement ( q , & error , & cols , & affected_rows , & resultset ) ;
if ( error ) {
proxy_warning ( " Query_Tool_Handler: failed refreshing target auth map: %s \n " , error ) ;
free ( error ) ;
if ( resultset ) {
delete resultset ;
}
} else {
GloMCPH - > load_target_auth_map ( resultset ) ;
}
}
const auto profiles = GloMCPH - > get_all_target_auth_contexts ( ) ;
const auto resolve_endpoint = [ & ] (
const std : : string & protocol ,
int hostgroup_id ,
std : : string & host ,
int & port ,
int & backends
) - > bool {
if ( GloAdmin = = NULL | | GloAdmin - > admindb = = NULL ) {
return false ;
}
const char * table_name = ( protocol = = " pgsql " ) ? " runtime_pgsql_servers " : " runtime_mysql_servers " ;
char * error = NULL ;
int cols = 0 ;
int affected_rows = 0 ;
SQLite3_result * resultset = NULL ;
std : : ostringstream sql ;
sql < < " SELECT hostname, port FROM " < < table_name
< < " WHERE hostgroup_id= " < < hostgroup_id
< < " AND UPPER(status)='ONLINE' "
< < " ORDER BY weight DESC, hostname, port " ;
GloAdmin - > admindb - > execute_statement ( sql . str ( ) . c_str ( ) , & error , & cols , & affected_rows , & resultset ) ;
if ( error ) {
proxy_warning ( " Query_Tool_Handler: endpoint resolution failed for %s/%d: %s \n " ,
protocol . c_str ( ) , hostgroup_id , error ) ;
free ( error ) ;
if ( resultset ) {
delete resultset ;
}
return false ;
}
if ( ! resultset | | resultset - > rows . empty ( ) ) {
if ( resultset ) {
delete resultset ;
}
return false ;
}
backends = resultset - > rows . size ( ) ;
host = resultset - > rows [ 0 ] - > fields [ 0 ] ? resultset - > rows [ 0 ] - > fields [ 0 ] : " " ;
port = resultset - > rows [ 0 ] - > fields [ 1 ] ? atoi ( resultset - > rows [ 0 ] - > fields [ 1 ] ) : ( ( protocol = = " pgsql " ) ? 5432 : 3306 ) ;
delete resultset ;
return ! host . empty ( ) ;
} ;
for ( const auto & ctx : profiles ) {
QueryTarget target ;
target . target_id = ctx . target_id ;
target . protocol = ctx . protocol ;
target . hostgroup_id = ctx . hostgroup_id ;
target . auth_profile_id = ctx . auth_profile_id ;
target . db_username = ctx . db_username ;
target . db_password = ctx . db_password ;
target . default_schema = ctx . default_schema ;
target . description = ctx . description ;
target . executable = false ;
int backend_count = 0 ;
if ( resolve_endpoint ( target . protocol , target . hostgroup_id , target . host , target . port , backend_count ) ) {
target . executable = ! target . db_username . empty ( ) ;
if ( target . description . empty ( ) ) {
target . description = " Hostgroup " + std : : to_string ( target . hostgroup_id ) +
" ( " + std : : to_string ( backend_count ) + " backend(s)) " ;
}
} else {
if ( target . description . empty ( ) ) {
target . description = " Hostgroup " + std : : to_string ( target . hostgroup_id ) + " (no ONLINE backends) " ;
}
}
target_registry . push_back ( target ) ;
}
for ( const auto & target : target_registry ) {
if ( target . executable ) {
default_target_id = target . target_id ;
break ;
}
}
}
const Query_Tool_Handler : : QueryTarget * Query_Tool_Handler : : resolve_target ( const std : : string & target_id ) {
const std : : string & resolved_target_id = target_id . empty ( ) ? default_target_id : target_id ;
if ( resolved_target_id . empty ( ) ) {
return NULL ;
}
for ( const auto & target : target_registry ) {
if ( target . target_id = = resolved_target_id ) {
return & target ;
}
}
return NULL ;
}
void * Query_Tool_Handler : : get_connection ( const std : : string & target_id ) {
const std : : string resolved_target = target_id . empty ( ) ? default_target_id : target_id ;
const QueryTarget * target = resolve_target ( resolved_target ) ;
if ( target = = NULL ) {
return NULL ;
}
pthread_mutex_lock ( & pool_lock ) ;
for ( auto & conn : connection_pool ) {
if ( ! conn . in_use ) {
if ( ! conn . in_use & & conn . target_id = = resolved_target & & conn . auth_profile_id = = target - > auth_profile_id ) {
conn . in_use = true ;
pthread_mutex_unlock ( & pool_lock ) ;
return conn . mysql ;
@ -403,7 +587,29 @@ void* Query_Tool_Handler::get_connection() {
}
pthread_mutex_unlock ( & pool_lock ) ;
proxy_error ( " Query_Tool_Handler: No available connection \n " ) ;
proxy_error ( " Query_Tool_Handler: No available connection for target '%s' \n " , resolved_target . c_str ( ) ) ;
return NULL ;
}
void * Query_Tool_Handler : : get_pgsql_connection ( const std : : string & target_id ) {
const std : : string resolved_target = target_id . empty ( ) ? default_target_id : target_id ;
const QueryTarget * target = resolve_target ( resolved_target ) ;
if ( target = = NULL ) {
return NULL ;
}
pthread_mutex_lock ( & pool_lock ) ;
for ( auto & conn : pgsql_connection_pool ) {
if ( ! conn . in_use & & conn . target_id = = resolved_target & & conn . auth_profile_id = = target - > auth_profile_id ) {
conn . in_use = true ;
pthread_mutex_unlock ( & pool_lock ) ;
return conn . pgconn ;
}
}
pthread_mutex_unlock ( & pool_lock ) ;
proxy_error ( " Query_Tool_Handler: No available pgsql connection for target '%s' \n " , resolved_target . c_str ( ) ) ;
return NULL ;
}
@ -415,7 +621,16 @@ void Query_Tool_Handler::return_connection(void* mysql_ptr) {
for ( auto & conn : connection_pool ) {
if ( conn . mysql = = mysql_ptr ) {
conn . in_use = false ;
break ;
pthread_mutex_unlock ( & pool_lock ) ;
return ;
}
}
for ( auto & conn : pgsql_connection_pool ) {
if ( conn . pgconn = = mysql_ptr ) {
conn . in_use = false ;
pthread_mutex_unlock ( & pool_lock ) ;
return ;
}
}
@ -435,12 +650,101 @@ Query_Tool_Handler::MySQLConnection* Query_Tool_Handler::find_connection(void* m
return nullptr ;
}
std : : string Query_Tool_Handler : : execute_query ( const std : : string & query ) {
void * mysql = get_connection ( ) ;
if ( ! mysql ) {
return " { \" error \" : \" No available connection \" } " ;
// Helper to find pgsql connection wrapper by PGconn pointer (thread-safe, acquires pool_lock)
Query_Tool_Handler : : PgSQLConnection * Query_Tool_Handler : : find_pgsql_connection ( void * pgconn_ptr ) {
pthread_mutex_lock ( & pool_lock ) ;
for ( auto & conn : pgsql_connection_pool ) {
if ( conn . pgconn = = pgconn_ptr ) {
pthread_mutex_unlock ( & pool_lock ) ;
return & conn ;
}
}
pthread_mutex_unlock ( & pool_lock ) ;
return nullptr ;
}
std : : string Query_Tool_Handler : : execute_query ( const std : : string & query , const std : : string & target_id ) {
const QueryTarget * target = resolve_target ( target_id ) ;
if ( target = = NULL ) {
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " Unknown target: " ) +
( target_id . empty ( ) ? default_target_id : target_id ) ;
return j . dump ( ) ;
}
if ( target - > protocol = = " pgsql " ) {
void * pgconn_v = get_pgsql_connection ( target_id ) ;
if ( ! pgconn_v ) {
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " No available pgsql connection for target: " ) +
( target_id . empty ( ) ? default_target_id : target_id ) ;
return j . dump ( ) ;
}
PGconn * pgconn = static_cast < PGconn * > ( pgconn_v ) ;
PGresult * res = PQexec ( pgconn , query . c_str ( ) ) ;
if ( res = = NULL ) {
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " PQexec returned null result " ) ;
return j . dump ( ) ;
}
ExecStatusType st = PQresultStatus ( res ) ;
if ( st ! = PGRES_TUPLES_OK & & st ! = PGRES_COMMAND_OK ) {
std : : string err = PQresultErrorMessage ( res ) ;
PQclear ( res ) ;
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = false ;
j [ " error " ] = err ;
return j . dump ( ) ;
}
if ( st = = PGRES_COMMAND_OK ) {
const char * tuples = PQcmdTuples ( res ) ;
long affected = 0 ;
if ( tuples & & tuples [ 0 ] ! = ' \0 ' ) {
affected = atol ( tuples ) ;
}
PQclear ( res ) ;
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = true ;
j [ " affected_rows " ] = affected ;
return j . dump ( ) ;
}
int num_fields = PQnfields ( res ) ;
int num_rows = PQntuples ( res ) ;
json results = json : : array ( ) ;
for ( int r = 0 ; r < num_rows ; r + + ) {
json row_data = json : : array ( ) ;
for ( int c = 0 ; c < num_fields ; c + + ) {
row_data . push_back ( PQgetisnull ( res , r , c ) ? " " : PQgetvalue ( res , r , c ) ) ;
}
results . push_back ( row_data ) ;
}
PQclear ( res ) ;
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = true ;
j [ " columns " ] = num_fields ;
j [ " rows " ] = results ;
return j . dump ( ) ;
}
void * mysql = get_connection ( target_id ) ;
if ( ! mysql ) {
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " No available mysql connection for target: " ) +
( target_id . empty ( ) ? default_target_id : target_id ) ;
return j . dump ( ) ;
}
MYSQL * mysql_ptr = static_cast < MYSQL * > ( mysql ) ;
if ( mysql_query ( mysql_ptr , query . c_str ( ) ) ) {
@ -490,13 +794,119 @@ std::string Query_Tool_Handler::execute_query(const std::string& query) {
// Execute query with optional schema switching
std : : string Query_Tool_Handler : : execute_query_with_schema (
const std : : string & query ,
const std : : string & schema
const std : : string & schema ,
const std : : string & target_id
) {
void * mysql = get_connection ( ) ;
if ( ! mysql ) {
return " { \" error \" : \" No available connection \" } " ;
const QueryTarget * target = resolve_target ( target_id ) ;
if ( target = = NULL ) {
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " Unknown target: " ) +
( target_id . empty ( ) ? default_target_id : target_id ) ;
return j . dump ( ) ;
}
if ( target - > protocol = = " pgsql " ) {
void * pgconn_v = get_pgsql_connection ( target_id ) ;
if ( ! pgconn_v ) {
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " No available pgsql connection for target: " ) +
( target_id . empty ( ) ? default_target_id : target_id ) ;
return j . dump ( ) ;
}
PGconn * pgconn = static_cast < PGconn * > ( pgconn_v ) ;
PgSQLConnection * conn_wrapper = find_pgsql_connection ( pgconn_v ) ;
if ( ! schema . empty ( ) & & conn_wrapper & & conn_wrapper - > current_schema ! = schema ) {
std : : string validated_schema = validate_sql_identifier_sqlite ( schema ) ;
if ( validated_schema . empty ( ) ) {
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = false ;
j [ " error " ] = " Invalid schema name: contains unsafe characters " ;
return j . dump ( ) ;
}
std : : string set_search_path = " SET search_path TO " + validated_schema ;
PGresult * set_res = PQexec ( pgconn , set_search_path . c_str ( ) ) ;
if ( set_res = = NULL | | PQresultStatus ( set_res ) ! = PGRES_COMMAND_OK ) {
std : : string err = set_res ? PQresultErrorMessage ( set_res ) : " set search_path failed " ;
if ( set_res ) {
PQclear ( set_res ) ;
}
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = false ;
j [ " error " ] = err ;
return j . dump ( ) ;
}
PQclear ( set_res ) ;
conn_wrapper - > current_schema = validated_schema ;
}
PGresult * res = PQexec ( pgconn , query . c_str ( ) ) ;
if ( res = = NULL ) {
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " PQexec returned null result " ) ;
return j . dump ( ) ;
}
ExecStatusType st = PQresultStatus ( res ) ;
if ( st ! = PGRES_TUPLES_OK & & st ! = PGRES_COMMAND_OK ) {
std : : string err = PQresultErrorMessage ( res ) ;
PQclear ( res ) ;
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = false ;
j [ " error " ] = err ;
return j . dump ( ) ;
}
if ( st = = PGRES_COMMAND_OK ) {
const char * tuples = PQcmdTuples ( res ) ;
long affected = 0 ;
if ( tuples & & tuples [ 0 ] ! = ' \0 ' ) {
affected = atol ( tuples ) ;
}
PQclear ( res ) ;
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = true ;
j [ " affected_rows " ] = affected ;
return j . dump ( ) ;
}
int num_fields = PQnfields ( res ) ;
int num_rows = PQntuples ( res ) ;
json results = json : : array ( ) ;
for ( int r = 0 ; r < num_rows ; r + + ) {
json row_data = json : : array ( ) ;
for ( int c = 0 ; c < num_fields ; c + + ) {
row_data . push_back ( PQgetisnull ( res , r , c ) ? " " : PQgetvalue ( res , r , c ) ) ;
}
results . push_back ( row_data ) ;
}
PQclear ( res ) ;
return_connection ( pgconn_v ) ;
json j ;
j [ " success " ] = true ;
j [ " columns " ] = num_fields ;
j [ " rows " ] = results ;
return j . dump ( ) ;
}
void * mysql = get_connection ( target_id ) ;
if ( ! mysql ) {
json j ;
j [ " success " ] = false ;
j [ " error " ] = std : : string ( " No available mysql connection for target: " ) +
( target_id . empty ( ) ? default_target_id : target_id ) ;
return j . dump ( ) ;
}
MYSQL * mysql_ptr = static_cast < MYSQL * > ( mysql ) ;
MySQLConnection * conn_wrapper = find_connection ( mysql ) ;
@ -686,18 +1096,25 @@ json Query_Tool_Handler::get_tool_list() {
// ============================================================
// INVENTORY TOOLS
// ============================================================
tools . push_back ( create_tool_schema (
" list_targets " ,
" List logical query targets. Each target maps internally to a ProxySQL hostgroup and routing policy. " ,
{ } ,
{ }
) ) ;
tools . push_back ( create_tool_schema (
" list_schemas " ,
" List all available schemas/databases " ,
{ } ,
{ { " page_token " , " string " } , { " page_size " , " integer " } }
{ { " page_token " , " string " } , { " page_size " , " integer " } , { " target_id " , " string " } }
) ) ;
tools . push_back ( create_tool_schema (
" list_tables " ,
" List tables in a schema " ,
{ " schema " } ,
{ { " page_token " , " string " } , { " page_size " , " integer " } , { " name_filter " , " string " }
{ { " page_token " , " string " } , { " page_size " , " integer " } , { " name_filter " , " string " } , { " target_id " , " string " } }
) ) ;
// ============================================================
@ -732,16 +1149,16 @@ json Query_Tool_Handler::get_tool_list() {
// ============================================================
tools . push_back ( create_tool_schema (
" run_sql_readonly " ,
" Execute a read-only SQL query with safety guardrails enforced. Optional schema parameter switches database context before query execution. " ,
" Execute a read-only SQL query with safety guardrails enforced. Optional schema parameter switches database context before query execution. target_id routes the query to a logical backend target. " ,
{ " sql " } ,
{ { " schema " , " string " } , { " " , " integer " } , { " timeout_sec " , " integer " } }
{ { " schema " , " string " } , { " target_id" , " string " } , { " max_rows" , " integer " } , { " timeout_sec " , " integer " } }
) ) ;
tools . push_back ( create_tool_schema (
" explain_sql " ,
" Explain a query execution plan using EXPLAIN or EXPLAIN ANALYZE " ,
{ " sql " } ,
{
{ {" target_id " , " string " } }
) ) ;
// ============================================================
@ -988,9 +1405,39 @@ json Query_Tool_Handler::execute_tool(const std::string& tool_name, const json&
// ============================================================
// INVENTORY TOOLS
// ============================================================
if ( tool_name = = " list_schemas " ) {
if ( tool_name = = " list_targets " ) {
refresh_target_registry ( ) ;
json targets = json : : array ( ) ;
for ( const auto & target : target_registry ) {
json t ;
t [ " target_id " ] = target . target_id ;
t [ " description " ] = target . description ;
json capabilities = json : : array ( ) ;
capabilities . push_back ( " inventory " ) ;
if ( target . executable ) {
capabilities . push_back ( " readonly_sql " ) ;
capabilities . push_back ( " explain " ) ;
}
t [ " capabilities " ] = capabilities ;
targets . push_back ( t ) ;
}
json payload ;
payload [ " targets " ] = targets ;
payload [ " default_target_id " ] = default_target_id ;
result = create_success_response ( payload ) ;
}
else if ( tool_name = = " list_schemas " ) {
std : : string target_id = json_string ( arguments , " target_id " ) ;
std : : string page_token = json_string ( arguments , " page_token " ) ;
int page_size = json_int ( arguments , " page_size " , 50 ) ;
if ( ! target_id . empty ( ) ) {
refresh_target_registry ( ) ;
const QueryTarget * target = resolve_target ( target_id ) ;
if ( target = = NULL ) {
return create_error_response ( " Unknown target_id: " + target_id ) ;
}
}
// Query catalog's schemas table instead of live database
char * error = NULL ;
@ -1038,9 +1485,25 @@ json Query_Tool_Handler::execute_tool(const std::string& tool_name, const json&
else if ( tool_name = = " list_tables " ) {
std : : string schema = json_string ( arguments , " schema " ) ;
std : : string target_id = json_string ( arguments , " target_id " ) ;
std : : string page_token = json_string ( arguments , " page_token " ) ;
int page_size = json_int ( arguments , " page_size " , 50 ) ;
std : : string name_filter = json_string ( arguments , " name_filter " ) ;
( void ) page_token ;
( void ) page_size ;
refresh_target_registry ( ) ;
const QueryTarget * target = resolve_target ( target_id ) ;
if ( target = = NULL ) {
result = create_error_response (
target_id . empty ( ) ? " No executable default target available " : " Unknown target_id: " + target_id
) ;
return result ;
}
if ( ! target - > executable ) {
result = create_error_response ( " Target is not executable by this handler " ) ;
return result ;
}
// Validate schema identifier if provided
if ( ! schema . empty ( ) ) {
@ -1053,17 +1516,27 @@ json Query_Tool_Handler::execute_tool(const std::string& tool_name, const json&
}
}
// TODO: Implement using MySQL connection
std : : ostringstream sql ;
sql < < " SHOW TABLES " ;
if ( ! schema . empty ( ) ) {
sql < < " FROM " < < schema ;
}
if ( ! name_filter . empty ( ) ) {
// Escape the name_filter to prevent SQL injection
sql < < " LIKE ' " < < escape_string_literal ( name_filter ) < < " ' " ;
if ( target - > protocol = = " pgsql " ) {
sql < < " SELECT table_name FROM information_schema.tables WHERE table_type='BASE TABLE' " ;
if ( ! schema . empty ( ) ) {
sql < < " AND table_schema=' " < < escape_string_literal ( schema ) < < " ' " ;
}
if ( ! name_filter . empty ( ) ) {
sql < < " AND table_name LIKE ' " < < escape_string_literal ( name_filter ) < < " ' " ;
}
sql < < " ORDER BY table_name " ;
} else {
sql < < " SHOW TABLES " ;
if ( ! schema . empty ( ) ) {
sql < < " FROM " < < schema ;
}
if ( ! name_filter . empty ( ) ) {
// Escape the name_filter to prevent SQL injection
sql < < " LIKE ' " < < escape_string_literal ( name_filter ) < < " ' " ;
}
}
std : : string query_result = execute_query ( sql . str ( ) ) ;
std : : string query_result = execute_query _with_schema ( sql . str ( ) , schema , target - > target_id ) ;
result = create_success_response ( json : : parse ( query_result ) ) ;
}
@ -1733,12 +2206,28 @@ json Query_Tool_Handler::execute_tool(const std::string& tool_name, const json&
else if ( tool_name = = " run_sql_readonly " ) {
std : : string sql = json_string ( arguments , " sql " ) ;
std : : string schema = json_string ( arguments , " schema " ) ;
std : : string target_id = json_string ( arguments , " target_id " ) ;
int max_rows = json_int ( arguments , " max_rows " , 200 ) ;
int timeout_sec = json_int ( arguments , " timeout_sec " , 2 ) ;
( void ) max_rows ;
( void ) timeout_sec ;
if ( sql . empty ( ) ) {
result = create_error_response ( " sql is required " ) ;
} else {
refresh_target_registry ( ) ;
const QueryTarget * target = resolve_target ( target_id ) ;
if ( target = = NULL ) {
result = create_error_response (
target_id . empty ( ) ? " No executable default target available " : " Unknown target_id: " + target_id
) ;
return result ;
}
if ( ! target - > executable ) {
result = create_error_response ( " Target is not executable by this handler " ) ;
return result ;
}
// ============================================================
// MCP QUERY RULES EVALUATION
// ============================================================
@ -1796,7 +2285,7 @@ json Query_Tool_Handler::execute_tool(const std::string& tool_name, const json&
} else if ( is_dangerous_query ( sql ) ) {
result = create_error_response ( " SQL contains dangerous operations " ) ;
} else {
std : : string query_result = execute_query_with_schema ( sql , schema ;
std : : string query_result = execute_query_with_schema ( sql , schema , target - > target_id );
try {
json result_json = json : : parse ( query_result ) ;
// Check if query actually failed
@ -1844,10 +2333,24 @@ json Query_Tool_Handler::execute_tool(const std::string& tool_name, const json&
else if ( tool_name = = " explain_sql " ) {
std : : string sql = json_string ( arguments , " sql " ) ;
std : : string target_id = json_string ( arguments , " target_id " ) ;
if ( sql . empty ( ) ) {
result = create_error_response ( " sql is required " ) ;
} else {
std : : string query_result = execute_query ( " EXPLAIN " + sql ) ;
refresh_target_registry ( ) ;
const QueryTarget * target = resolve_target ( target_id ) ;
if ( target = = NULL ) {
result = create_error_response (
target_id . empty ( ) ? " No executable default target available " : " Unknown target_id: " + target_id
) ;
return result ;
}
if ( ! target - > executable ) {
result = create_error_response ( " Target is not executable by this handler " ) ;
return result ;
}
std : : string query_result = execute_query ( " EXPLAIN " + sql , target - > target_id ) ;
try {
result = create_success_response ( json : : parse ( query_result ) ) ;
} catch ( . . . ) {
Rene Cannao
2 months ago