github.com/mdaxf/iac@v0.0.0-20240519030858-58a061660378/vendor_skip/go.mongodb.org/mongo-driver/bson/bsoncodec/byte_slice_codec.go (about)

     1  // Copyright (C) MongoDB, Inc. 2017-present.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License"); you may
     4  // not use this file except in compliance with the License. You may obtain
     5  // a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
     6  
     7  package bsoncodec
     8  
     9  import (
    10  	"fmt"
    11  	"reflect"
    12  
    13  	"go.mongodb.org/mongo-driver/bson/bsonoptions"
    14  	"go.mongodb.org/mongo-driver/bson/bsonrw"
    15  	"go.mongodb.org/mongo-driver/bson/bsontype"
    16  )
    17  
    18  // ByteSliceCodec is the Codec used for []byte values.
    19  //
    20  // Deprecated: Use [go.mongodb.org/mongo-driver/bson.NewRegistry] to get a registry with the
    21  // ByteSliceCodec registered.
    22  type ByteSliceCodec struct {
    23  	// EncodeNilAsEmpty causes EncodeValue to marshal nil Go byte slices as empty BSON binary values
    24  	// instead of BSON null.
    25  	//
    26  	// Deprecated: Use bson.Encoder.NilByteSliceAsEmpty instead.
    27  	EncodeNilAsEmpty bool
    28  }
    29  
    30  var (
    31  	defaultByteSliceCodec = NewByteSliceCodec()
    32  
    33  	// Assert that defaultByteSliceCodec satisfies the typeDecoder interface, which allows it to be
    34  	// used by collection type decoders (e.g. map, slice, etc) to set individual values in a
    35  	// collection.
    36  	_ typeDecoder = defaultByteSliceCodec
    37  )
    38  
    39  // NewByteSliceCodec returns a ByteSliceCodec with options opts.
    40  //
    41  // Deprecated: Use [go.mongodb.org/mongo-driver/bson.NewRegistry] to get a registry with the
    42  // ByteSliceCodec registered.
    43  func NewByteSliceCodec(opts ...*bsonoptions.ByteSliceCodecOptions) *ByteSliceCodec {
    44  	byteSliceOpt := bsonoptions.MergeByteSliceCodecOptions(opts...)
    45  	codec := ByteSliceCodec{}
    46  	if byteSliceOpt.EncodeNilAsEmpty != nil {
    47  		codec.EncodeNilAsEmpty = *byteSliceOpt.EncodeNilAsEmpty
    48  	}
    49  	return &codec
    50  }
    51  
    52  // EncodeValue is the ValueEncoder for []byte.
    53  func (bsc *ByteSliceCodec) EncodeValue(ec EncodeContext, vw bsonrw.ValueWriter, val reflect.Value) error {
    54  	if !val.IsValid() || val.Type() != tByteSlice {
    55  		return ValueEncoderError{Name: "ByteSliceEncodeValue", Types: []reflect.Type{tByteSlice}, Received: val}
    56  	}
    57  	if val.IsNil() && !bsc.EncodeNilAsEmpty && !ec.nilByteSliceAsEmpty {
    58  		return vw.WriteNull()
    59  	}
    60  	return vw.WriteBinary(val.Interface().([]byte))
    61  }
    62  
    63  func (bsc *ByteSliceCodec) decodeType(_ DecodeContext, vr bsonrw.ValueReader, t reflect.Type) (reflect.Value, error) {
    64  	if t != tByteSlice {
    65  		return emptyValue, ValueDecoderError{
    66  			Name:     "ByteSliceDecodeValue",
    67  			Types:    []reflect.Type{tByteSlice},
    68  			Received: reflect.Zero(t),
    69  		}
    70  	}
    71  
    72  	var data []byte
    73  	var err error
    74  	switch vrType := vr.Type(); vrType {
    75  	case bsontype.String:
    76  		str, err := vr.ReadString()
    77  		if err != nil {
    78  			return emptyValue, err
    79  		}
    80  		data = []byte(str)
    81  	case bsontype.Symbol:
    82  		sym, err := vr.ReadSymbol()
    83  		if err != nil {
    84  			return emptyValue, err
    85  		}
    86  		data = []byte(sym)
    87  	case bsontype.Binary:
    88  		var subtype byte
    89  		data, subtype, err = vr.ReadBinary()
    90  		if err != nil {
    91  			return emptyValue, err
    92  		}
    93  		if subtype != bsontype.BinaryGeneric && subtype != bsontype.BinaryBinaryOld {
    94  			return emptyValue, decodeBinaryError{subtype: subtype, typeName: "[]byte"}
    95  		}
    96  	case bsontype.Null:
    97  		err = vr.ReadNull()
    98  	case bsontype.Undefined:
    99  		err = vr.ReadUndefined()
   100  	default:
   101  		return emptyValue, fmt.Errorf("cannot decode %v into a []byte", vrType)
   102  	}
   103  	if err != nil {
   104  		return emptyValue, err
   105  	}
   106  
   107  	return reflect.ValueOf(data), nil
   108  }
   109  
   110  // DecodeValue is the ValueDecoder for []byte.
   111  func (bsc *ByteSliceCodec) DecodeValue(dc DecodeContext, vr bsonrw.ValueReader, val reflect.Value) error {
   112  	if !val.CanSet() || val.Type() != tByteSlice {
   113  		return ValueDecoderError{Name: "ByteSliceDecodeValue", Types: []reflect.Type{tByteSlice}, Received: val}
   114  	}
   115  
   116  	elem, err := bsc.decodeType(dc, vr, tByteSlice)
   117  	if err != nil {
   118  		return err
   119  	}
   120  
   121  	val.Set(elem)
   122  	return nil
   123  }