102 lines
3.1 KiB
Go
102 lines
3.1 KiB
Go
|
/*
|
||
|
|
Copyright 2017 Google Inc. All Rights Reserved.
|
||
|
|
|
||
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
you may not use this file except in compliance with the License.
|
||
|
|
You may obtain a copy of the License at
|
||
|
|
|
||
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
|
||
|
|
Unless required by applicable law or agreed to in writing, software
|
||
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
See the License for the specific language governing permissions and
|
||
|
|
limitations under the License.
|
||
|
|
*/
|
||
|
|
|
||
|
|
package spanner
|
||
|
|
|
||
|
|
import (
|
||
|
|
"errors"
|
||
|
|
"fmt"
|
||
|
|
|
||
|
|
proto3 "github.com/golang/protobuf/ptypes/struct"
|
||
|
|
|
||
|
|
sppb "google.golang.org/genproto/googleapis/spanner/v1"
|
||
|
|
"google.golang.org/grpc/codes"
|
||
|
|
)
|
||
|
|
|
||
|
|
// A Statement is a SQL query with named parameters.
|
||
|
|
//
|
||
|
|
// A parameter placeholder consists of '@' followed by the parameter name.
|
||
|
|
// Parameter names consist of any combination of letters, numbers, and
|
||
|
|
// underscores. Names may be entirely numeric (e.g., "WHERE m.id = @5").
|
||
|
|
// Parameters may appear anywhere that a literal value is expected. The same
|
||
|
|
// parameter name may be used more than once. It is an error to execute a
|
||
|
|
// statement with unbound parameters. On the other hand, it is allowable to
|
||
|
|
// bind parameter names that are not used.
|
||
|
|
//
|
||
|
|
// See the documentation of the Row type for how Go types are mapped to Cloud
|
||
|
|
// Spanner types.
|
||
|
|
type Statement struct {
|
||
|
|
SQL string
|
||
|
|
Params map[string]interface{}
|
||
|
|
}
|
||
|
|
|
||
|
|
// NewStatement returns a Statement with the given SQL and an empty Params map.
|
||
|
|
func NewStatement(sql string) Statement {
|
||
|
|
return Statement{SQL: sql, Params: map[string]interface{}{}}
|
||
|
|
}
|
||
|
|
|
||
|
|
// errBindParam returns error for not being able to bind parameter to query request.
|
||
|
|
func errBindParam(k string, v interface{}, err error) error {
|
||
|
|
if err == nil {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
se, ok := toSpannerError(err).(*Error)
|
||
|
|
if !ok {
|
||
|
|
return spannerErrorf(codes.InvalidArgument, "failed to bind query parameter(name: %q, value: %v), error = <%v>", k, v, err)
|
||
|
|
}
|
||
|
|
se.decorate(fmt.Sprintf("failed to bind query parameter(name: %q, value: %v)", k, v))
|
||
|
|
return se
|
||
|
|
}
|
||
|
|
|
||
|
|
var (
|
||
|
|
errNilParam = errors.New("use T(nil), not nil")
|
||
|
|
errNoType = errors.New("no type information")
|
||
|
|
)
|
||
|
|
|
||
|
|
// bindParams binds parameters in a Statement to a sppb.ExecuteSqlRequest or sppb.PartitionQueryRequest.
|
||
|
|
func (s *Statement) bindParams(i interface{}) error {
|
||
|
|
params := &proto3.Struct{
|
||
|
|
Fields: map[string]*proto3.Value{},
|
||
|
|
}
|
||
|
|
paramTypes := map[string]*sppb.Type{}
|
||
|
|
for k, v := range s.Params {
|
||
|
|
if v == nil {
|
||
|
|
return errBindParam(k, v, errNilParam)
|
||
|
|
}
|
||
|
|
val, t, err := encodeValue(v)
|
||
|
|
if err != nil {
|
||
|
|
return errBindParam(k, v, err)
|
||
|
|
}
|
||
|
|
if t == nil { // should not happen, because of nil check above
|
||
|
|
return errBindParam(k, v, errNoType)
|
||
|
|
}
|
||
|
|
params.Fields[k] = val
|
||
|
|
paramTypes[k] = t
|
||
|
|
}
|
||
|
|
|
||
|
|
switch r := i.(type) {
|
||
|
|
default:
|
||
|
|
return fmt.Errorf("failed to bind query parameter, unexpected request type: %v", r)
|
||
|
|
case *sppb.ExecuteSqlRequest:
|
||
|
|
r.Params = params
|
||
|
|
r.ParamTypes = paramTypes
|
||
|
|
case *sppb.PartitionQueryRequest:
|
||
|
|
r.Params = params
|
||
|
|
r.ParamTypes = paramTypes
|
||
|
|
}
|
||
|
|
return nil
|
||
|
|
}
|