mirror of
https://github.com/go-gitea/gitea
synced 2024-10-31 23:34:25 +00:00
119 lines
3.3 KiB
Go
Vendored
119 lines
3.3 KiB
Go
Vendored
// Copyright (C) MongoDB, Inc. 2017-present.
|
|
//
|
|
// 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
|
|
|
|
package bson
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"reflect"
|
|
"sync"
|
|
|
|
"go.mongodb.org/mongo-driver/bson/bsoncodec"
|
|
"go.mongodb.org/mongo-driver/bson/bsonrw"
|
|
)
|
|
|
|
// ErrDecodeToNil is the error returned when trying to decode to a nil value
|
|
var ErrDecodeToNil = errors.New("cannot Decode to nil value")
|
|
|
|
// This pool is used to keep the allocations of Decoders down. This is only used for the Marshal*
|
|
// methods and is not consumable from outside of this package. The Decoders retrieved from this pool
|
|
// must have both Reset and SetRegistry called on them.
|
|
var decPool = sync.Pool{
|
|
New: func() interface{} {
|
|
return new(Decoder)
|
|
},
|
|
}
|
|
|
|
// A Decoder reads and decodes BSON documents from a stream. It reads from a bsonrw.ValueReader as
|
|
// the source of BSON data.
|
|
type Decoder struct {
|
|
dc bsoncodec.DecodeContext
|
|
vr bsonrw.ValueReader
|
|
}
|
|
|
|
// NewDecoder returns a new decoder that uses the DefaultRegistry to read from vr.
|
|
func NewDecoder(vr bsonrw.ValueReader) (*Decoder, error) {
|
|
if vr == nil {
|
|
return nil, errors.New("cannot create a new Decoder with a nil ValueReader")
|
|
}
|
|
|
|
return &Decoder{
|
|
dc: bsoncodec.DecodeContext{Registry: DefaultRegistry},
|
|
vr: vr,
|
|
}, nil
|
|
}
|
|
|
|
// NewDecoderWithContext returns a new decoder that uses DecodeContext dc to read from vr.
|
|
func NewDecoderWithContext(dc bsoncodec.DecodeContext, vr bsonrw.ValueReader) (*Decoder, error) {
|
|
if dc.Registry == nil {
|
|
dc.Registry = DefaultRegistry
|
|
}
|
|
if vr == nil {
|
|
return nil, errors.New("cannot create a new Decoder with a nil ValueReader")
|
|
}
|
|
|
|
return &Decoder{
|
|
dc: dc,
|
|
vr: vr,
|
|
}, nil
|
|
}
|
|
|
|
// Decode reads the next BSON document from the stream and decodes it into the
|
|
// value pointed to by val.
|
|
//
|
|
// The documentation for Unmarshal contains details about of BSON into a Go
|
|
// value.
|
|
func (d *Decoder) Decode(val interface{}) error {
|
|
if unmarshaler, ok := val.(Unmarshaler); ok {
|
|
// TODO(skriptble): Reuse a []byte here and use the AppendDocumentBytes method.
|
|
buf, err := bsonrw.Copier{}.CopyDocumentToBytes(d.vr)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return unmarshaler.UnmarshalBSON(buf)
|
|
}
|
|
|
|
rval := reflect.ValueOf(val)
|
|
switch rval.Kind() {
|
|
case reflect.Ptr:
|
|
if rval.IsNil() {
|
|
return ErrDecodeToNil
|
|
}
|
|
rval = rval.Elem()
|
|
case reflect.Map:
|
|
if rval.IsNil() {
|
|
return ErrDecodeToNil
|
|
}
|
|
default:
|
|
return fmt.Errorf("argument to Decode must be a pointer or a map, but got %v", rval)
|
|
}
|
|
decoder, err := d.dc.LookupDecoder(rval.Type())
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return decoder.DecodeValue(d.dc, d.vr, rval)
|
|
}
|
|
|
|
// Reset will reset the state of the decoder, using the same *DecodeContext used in
|
|
// the original construction but using vr for reading.
|
|
func (d *Decoder) Reset(vr bsonrw.ValueReader) error {
|
|
d.vr = vr
|
|
return nil
|
|
}
|
|
|
|
// SetRegistry replaces the current registry of the decoder with r.
|
|
func (d *Decoder) SetRegistry(r *bsoncodec.Registry) error {
|
|
d.dc.Registry = r
|
|
return nil
|
|
}
|
|
|
|
// SetContext replaces the current registry of the decoder with dc.
|
|
func (d *Decoder) SetContext(dc bsoncodec.DecodeContext) error {
|
|
d.dc = dc
|
|
return nil
|
|
}
|