restic/vendor/cloud.google.com/go/bigquery/params.go

266 lines
7.1 KiB
Go

// Copyright 2016 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 bigquery
import (
"encoding/base64"
"errors"
"fmt"
"reflect"
"regexp"
"time"
"cloud.google.com/go/civil"
"cloud.google.com/go/internal/fields"
bq "google.golang.org/api/bigquery/v2"
)
var (
// See https://cloud.google.com/bigquery/docs/reference/standard-sql/data-types#timestamp-type.
timestampFormat = "2006-01-02 15:04:05.999999-07:00"
// See https://cloud.google.com/bigquery/docs/reference/rest/v2/tables#schema.fields.name
validFieldName = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]{0,127}$")
)
func bqTagParser(t reflect.StructTag) (name string, keep bool, other interface{}, err error) {
if s := t.Get("bigquery"); s != "" {
if s == "-" {
return "", false, nil, nil
}
if !validFieldName.MatchString(s) {
return "", false, nil, errInvalidFieldName
}
return s, true, nil, nil
}
return "", true, nil, nil
}
var fieldCache = fields.NewCache(bqTagParser, nil, nil)
var (
int64ParamType = &bq.QueryParameterType{Type: "INT64"}
float64ParamType = &bq.QueryParameterType{Type: "FLOAT64"}
boolParamType = &bq.QueryParameterType{Type: "BOOL"}
stringParamType = &bq.QueryParameterType{Type: "STRING"}
bytesParamType = &bq.QueryParameterType{Type: "BYTES"}
dateParamType = &bq.QueryParameterType{Type: "DATE"}
timeParamType = &bq.QueryParameterType{Type: "TIME"}
dateTimeParamType = &bq.QueryParameterType{Type: "DATETIME"}
timestampParamType = &bq.QueryParameterType{Type: "TIMESTAMP"}
)
var (
typeOfDate = reflect.TypeOf(civil.Date{})
typeOfTime = reflect.TypeOf(civil.Time{})
typeOfDateTime = reflect.TypeOf(civil.DateTime{})
typeOfGoTime = reflect.TypeOf(time.Time{})
)
// A QueryParameter is a parameter to a query.
type QueryParameter struct {
// Name is used for named parameter mode.
// It must match the name in the query case-insensitively.
Name string
// Value is the value of the parameter.
// The following Go types are supported, with their corresponding
// Bigquery types:
// int, int8, int16, int32, int64, uint8, uint16, uint32: INT64
// Note that uint, uint64 and uintptr are not supported, because
// they may contain values that cannot fit into a 64-bit signed integer.
// float32, float64: FLOAT64
// bool: BOOL
// string: STRING
// []byte: BYTES
// time.Time: TIMESTAMP
// Arrays and slices of the above.
// Structs of the above. Only the exported fields are used.
Value interface{}
}
func (p QueryParameter) toRaw() (*bq.QueryParameter, error) {
pv, err := paramValue(reflect.ValueOf(p.Value))
if err != nil {
return nil, err
}
pt, err := paramType(reflect.TypeOf(p.Value))
if err != nil {
return nil, err
}
return &bq.QueryParameter{
Name: p.Name,
ParameterValue: &pv,
ParameterType: pt,
}, nil
}
func paramType(t reflect.Type) (*bq.QueryParameterType, error) {
if t == nil {
return nil, errors.New("bigquery: nil parameter")
}
switch t {
case typeOfDate:
return dateParamType, nil
case typeOfTime:
return timeParamType, nil
case typeOfDateTime:
return dateTimeParamType, nil
case typeOfGoTime:
return timestampParamType, nil
}
switch t.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint8, reflect.Uint16, reflect.Uint32:
return int64ParamType, nil
case reflect.Float32, reflect.Float64:
return float64ParamType, nil
case reflect.Bool:
return boolParamType, nil
case reflect.String:
return stringParamType, nil
case reflect.Slice:
if t.Elem().Kind() == reflect.Uint8 {
return bytesParamType, nil
}
fallthrough
case reflect.Array:
et, err := paramType(t.Elem())
if err != nil {
return nil, err
}
return &bq.QueryParameterType{Type: "ARRAY", ArrayType: et}, nil
case reflect.Ptr:
if t.Elem().Kind() != reflect.Struct {
break
}
t = t.Elem()
fallthrough
case reflect.Struct:
var fts []*bq.QueryParameterTypeStructTypes
fields, err := fieldCache.Fields(t)
if err != nil {
return nil, err
}
for _, f := range fields {
pt, err := paramType(f.Type)
if err != nil {
return nil, err
}
fts = append(fts, &bq.QueryParameterTypeStructTypes{
Name: f.Name,
Type: pt,
})
}
return &bq.QueryParameterType{Type: "STRUCT", StructTypes: fts}, nil
}
return nil, fmt.Errorf("bigquery: Go type %s cannot be represented as a parameter type", t)
}
func paramValue(v reflect.Value) (bq.QueryParameterValue, error) {
var res bq.QueryParameterValue
if !v.IsValid() {
return res, errors.New("bigquery: nil parameter")
}
t := v.Type()
switch t {
case typeOfDate:
res.Value = v.Interface().(civil.Date).String()
return res, nil
case typeOfTime:
// civil.Time has nanosecond resolution, but BigQuery TIME only microsecond.
res.Value = civilTimeParamString(v.Interface().(civil.Time))
return res, nil
case typeOfDateTime:
dt := v.Interface().(civil.DateTime)
res.Value = dt.Date.String() + " " + civilTimeParamString(dt.Time)
return res, nil
case typeOfGoTime:
res.Value = v.Interface().(time.Time).Format(timestampFormat)
return res, nil
}
switch t.Kind() {
case reflect.Slice:
if t.Elem().Kind() == reflect.Uint8 {
res.Value = base64.StdEncoding.EncodeToString(v.Interface().([]byte))
return res, nil
}
fallthrough
case reflect.Array:
var vals []*bq.QueryParameterValue
for i := 0; i < v.Len(); i++ {
val, err := paramValue(v.Index(i))
if err != nil {
return bq.QueryParameterValue{}, err
}
vals = append(vals, &val)
}
return bq.QueryParameterValue{ArrayValues: vals}, nil
case reflect.Ptr:
if t.Elem().Kind() != reflect.Struct {
return res, fmt.Errorf("bigquery: Go type %s cannot be represented as a parameter value", t)
}
t = t.Elem()
v = v.Elem()
if !v.IsValid() {
// nil pointer becomes empty value
return res, nil
}
fallthrough
case reflect.Struct:
fields, err := fieldCache.Fields(t)
if err != nil {
return bq.QueryParameterValue{}, err
}
res.StructValues = map[string]bq.QueryParameterValue{}
for _, f := range fields {
fv := v.FieldByIndex(f.Index)
fp, err := paramValue(fv)
if err != nil {
return bq.QueryParameterValue{}, err
}
res.StructValues[f.Name] = fp
}
return res, nil
}
// None of the above: assume a scalar type. (If it's not a valid type,
// paramType will catch the error.)
res.Value = fmt.Sprint(v.Interface())
return res, nil
}
func civilTimeParamString(t civil.Time) string {
if t.Nanosecond == 0 {
return t.String()
} else {
micro := (t.Nanosecond + 500) / 1000 // round to nearest microsecond
t.Nanosecond = 0
return t.String() + fmt.Sprintf(".%06d", micro)
}
}