ipld-eth-server/vendor/gopkg.in/DataDog/dd-trace-go.v1/contrib/database/sql/stmt.go
2018-09-11 16:30:29 -05:00

83 lines
2.0 KiB
Go

package sql
import (
"context"
"database/sql/driver"
"errors"
"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
)
var _ driver.Stmt = (*tracedStmt)(nil)
// tracedStmt is traced version of sql.Stmt
type tracedStmt struct {
driver.Stmt
*traceParams
ctx context.Context
query string
}
// Close sends a span before closing a statement
func (s *tracedStmt) Close() (err error) {
span := s.newChildSpanFromContext(s.ctx, "Close", "")
defer func() {
span.Finish(tracer.WithError(err))
}()
return s.Stmt.Close()
}
// ExecContext is needed to implement the driver.StmtExecContext interface
func (s *tracedStmt) ExecContext(ctx context.Context, args []driver.NamedValue) (res driver.Result, err error) {
span := s.newChildSpanFromContext(ctx, "Exec", s.query)
defer func() {
span.Finish(tracer.WithError(err))
}()
if stmtExecContext, ok := s.Stmt.(driver.StmtExecContext); ok {
return stmtExecContext.ExecContext(ctx, args)
}
dargs, err := namedValueToValue(args)
if err != nil {
return nil, err
}
select {
case <-ctx.Done():
return nil, ctx.Err()
default:
}
return s.Exec(dargs)
}
// QueryContext is needed to implement the driver.StmtQueryContext interface
func (s *tracedStmt) QueryContext(ctx context.Context, args []driver.NamedValue) (rows driver.Rows, err error) {
span := s.newChildSpanFromContext(ctx, "Query", s.query)
defer func() {
span.Finish(tracer.WithError(err))
}()
if stmtQueryContext, ok := s.Stmt.(driver.StmtQueryContext); ok {
return stmtQueryContext.QueryContext(ctx, args)
}
dargs, err := namedValueToValue(args)
if err != nil {
return nil, err
}
select {
case <-ctx.Done():
return nil, ctx.Err()
default:
}
return s.Query(dargs)
}
// copied from stdlib database/sql package: src/database/sql/ctxutil.go
func namedValueToValue(named []driver.NamedValue) ([]driver.Value, error) {
dargs := make([]driver.Value, len(named))
for n, param := range named {
if len(param.Name) > 0 {
return nil, errors.New("sql: driver does not support the use of Named Parameters")
}
dargs[n] = param.Value
}
return dargs, nil
}