| // 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 bsonx |
| |
| import ( |
| "bytes" |
| "fmt" |
| |
| "github.com/mongodb/mongo-go-driver/bson/bsontype" |
| "github.com/mongodb/mongo-go-driver/x/bsonx/bsoncore" |
| ) |
| |
| // MDoc is an unordered, type safe, concise BSON document representation. This type should not be |
| // used if you require ordering of values or duplicate keys. |
| type MDoc map[string]Val |
| |
| // ReadMDoc will create a Doc using the provided slice of bytes. If the |
| // slice of bytes is not a valid BSON document, this method will return an error. |
| func ReadMDoc(b []byte) (MDoc, error) { |
| doc := make(MDoc, 0) |
| err := doc.UnmarshalBSON(b) |
| if err != nil { |
| return nil, err |
| } |
| return doc, nil |
| } |
| |
| // Copy makes a shallow copy of this document. |
| func (d MDoc) Copy() MDoc { |
| d2 := make(MDoc, len(d)) |
| for k, v := range d { |
| d2[k] = v |
| } |
| return d2 |
| } |
| |
| // Lookup searches the document and potentially subdocuments or arrays for the |
| // provided key. Each key provided to this method represents a layer of depth. |
| // |
| // This method will return an empty Value if they key does not exist. To know if they key actually |
| // exists, use LookupErr. |
| func (d MDoc) Lookup(key ...string) Val { |
| val, _ := d.LookupErr(key...) |
| return val |
| } |
| |
| // LookupErr searches the document and potentially subdocuments or arrays for the |
| // provided key. Each key provided to this method represents a layer of depth. |
| func (d MDoc) LookupErr(key ...string) (Val, error) { |
| elem, err := d.LookupElementErr(key...) |
| return elem.Value, err |
| } |
| |
| // LookupElement searches the document and potentially subdocuments or arrays for the |
| // provided key. Each key provided to this method represents a layer of depth. |
| // |
| // This method will return an empty Element if they key does not exist. To know if they key actually |
| // exists, use LookupElementErr. |
| func (d MDoc) LookupElement(key ...string) Elem { |
| elem, _ := d.LookupElementErr(key...) |
| return elem |
| } |
| |
| // LookupElementErr searches the document and potentially subdocuments for the |
| // provided key. Each key provided to this method represents a layer of depth. |
| func (d MDoc) LookupElementErr(key ...string) (Elem, error) { |
| // KeyNotFound operates by being created where the error happens and then the depth is |
| // incremented by 1 as each function unwinds. Whenever this function returns, it also assigns |
| // the Key slice to the key slice it has. This ensures that the proper depth is identified and |
| // the proper keys. |
| if len(key) == 0 { |
| return Elem{}, KeyNotFound{Key: key} |
| } |
| |
| var elem Elem |
| var err error |
| val, ok := d[key[0]] |
| if !ok { |
| return Elem{}, KeyNotFound{Key: key} |
| } |
| |
| if len(key) == 1 { |
| return Elem{Key: key[0], Value: val}, nil |
| } |
| |
| switch val.Type() { |
| case bsontype.EmbeddedDocument: |
| switch tt := val.primitive.(type) { |
| case Doc: |
| elem, err = tt.LookupElementErr(key[1:]...) |
| case MDoc: |
| elem, err = tt.LookupElementErr(key[1:]...) |
| } |
| default: |
| return Elem{}, KeyNotFound{Type: val.Type()} |
| } |
| switch tt := err.(type) { |
| case KeyNotFound: |
| tt.Depth++ |
| tt.Key = key |
| return Elem{}, tt |
| case nil: |
| return elem, nil |
| default: |
| return Elem{}, err // We can't actually hit this. |
| } |
| } |
| |
| // MarshalBSONValue implements the bsoncodec.ValueMarshaler interface. |
| // |
| // This method will never return an error. |
| func (d MDoc) MarshalBSONValue() (bsontype.Type, []byte, error) { |
| if d == nil { |
| // TODO: Should we do this? |
| return bsontype.Null, nil, nil |
| } |
| data, _ := d.MarshalBSON() |
| return bsontype.EmbeddedDocument, data, nil |
| } |
| |
| // MarshalBSON implements the Marshaler interface. |
| // |
| // This method will never return an error. |
| func (d MDoc) MarshalBSON() ([]byte, error) { return d.AppendMarshalBSON(nil) } |
| |
| // AppendMarshalBSON marshals Doc to BSON bytes, appending to dst. |
| // |
| // This method will never return an error. |
| func (d MDoc) AppendMarshalBSON(dst []byte) ([]byte, error) { |
| idx, dst := bsoncore.ReserveLength(dst) |
| for k, v := range d { |
| t, data, _ := v.MarshalBSONValue() // Value.MarshalBSONValue never returns an error. |
| dst = append(dst, byte(t)) |
| dst = append(dst, k...) |
| dst = append(dst, 0x00) |
| dst = append(dst, data...) |
| } |
| dst = append(dst, 0x00) |
| dst = bsoncore.UpdateLength(dst, idx, int32(len(dst[idx:]))) |
| return dst, nil |
| } |
| |
| // UnmarshalBSON implements the Unmarshaler interface. |
| func (d *MDoc) UnmarshalBSON(b []byte) error { |
| if d == nil { |
| return ErrNilDocument |
| } |
| |
| if err := bsoncore.Document(b).Validate(); err != nil { |
| return err |
| } |
| |
| elems, err := bsoncore.Document(b).Elements() |
| if err != nil { |
| return err |
| } |
| var val Val |
| for _, elem := range elems { |
| rawv := elem.Value() |
| err = val.UnmarshalBSONValue(rawv.Type, rawv.Data) |
| if err != nil { |
| return err |
| } |
| (*d)[elem.Key()] = val |
| } |
| return nil |
| } |
| |
| // Equal compares this document to another, returning true if they are equal. |
| func (d MDoc) Equal(id IDoc) bool { |
| switch tt := id.(type) { |
| case MDoc: |
| d2 := tt |
| if len(d) != len(d2) { |
| return false |
| } |
| for key, value := range d { |
| value2, ok := d2[key] |
| if !ok { |
| return false |
| } |
| if !value.Equal(value2) { |
| return false |
| } |
| } |
| case Doc: |
| unique := make(map[string]struct{}, 0) |
| for _, elem := range tt { |
| unique[elem.Key] = struct{}{} |
| val, ok := d[elem.Key] |
| if !ok { |
| return false |
| } |
| if !val.Equal(elem.Value) { |
| return false |
| } |
| } |
| if len(unique) != len(d) { |
| return false |
| } |
| case nil: |
| return d == nil |
| default: |
| return false |
| } |
| |
| return true |
| } |
| |
| // String implements the fmt.Stringer interface. |
| func (d MDoc) String() string { |
| var buf bytes.Buffer |
| buf.Write([]byte("bson.Document{")) |
| first := true |
| for key, value := range d { |
| if !first { |
| buf.Write([]byte(", ")) |
| } |
| fmt.Fprintf(&buf, "%v", Elem{Key: key, Value: value}) |
| first = false |
| } |
| buf.WriteByte('}') |
| |
| return buf.String() |
| } |
| |
| func (MDoc) idoc() {} |