MSSQL: Add connection timeout setting in configuration page (#58631)

* MSSQL add connection timeout

* add docs

* Update docs and add min value to the timeout setting

pkg/tsdb/mssql/mssql.go

@@ -55,10 +55,11 @@ func (s *Service) QueryData(ctx context.Context, req *backend.QueryDataRequest)
 func newInstanceSettings(cfg *setting.Cfg) datasource.InstanceFactoryFunc {
 	return func(settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
 		jsonData := sqleng.JsonData{
-			MaxOpenConns:    0,
-			MaxIdleConns:    2,
-			ConnMaxLifetime: 14400,
-			Encrypt:         "false",
+			MaxOpenConns:      0,
+			MaxIdleConns:      2,
+			ConnMaxLifetime:   14400,
+			Encrypt:           "false",
+			ConnectionTimeout: 0,
 		}
 
 		err := json.Unmarshal(settings.JSONData, &jsonData)
@@ -171,6 +172,11 @@ func generateConnectionString(dsInfo sqleng.DataSourceInfo) (string, error) {
 	} else if encrypt == "disable" {
 		connStr += fmt.Sprintf("encrypt=%s;", dsInfo.JsonData.Encrypt)
 	}
+
+	if dsInfo.JsonData.ConnectionTimeout != 0 {
+		connStr += fmt.Sprintf("connection timeout=%d;", dsInfo.JsonData.ConnectionTimeout)
+	}
+
 	return connStr, nil
 }
 

pkg/tsdb/sqleng/sql_engine.go

@@ -54,6 +54,7 @@ type JsonData struct {
 	MaxOpenConns        int    `json:"maxOpenConns"`
 	MaxIdleConns        int    `json:"maxIdleConns"`
 	ConnMaxLifetime     int    `json:"connMaxLifetime"`
+	ConnectionTimeout   int    `json:"connectionTimeout"`
 	Timescaledb         bool   `json:"timescaledb"`
 	Mode                string `json:"sslmode"`
 	ConfigurationMethod string `json:"tlsConfigurationMethod"`