1// Copyright (C) MongoDB, Inc. 2014-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 7package json 8 9import ( 10 "fmt" 11 "gopkg.in/mgo.v2/bson" 12 "reflect" 13) 14 15// Transition functions for recognizing DBPointer. 16// Adapted from encoding/json/scanner.go. 17 18// stateDB is the state after reading `DB`. 19func stateDBP(s *scanner, c int) int { 20 if c == 'o' { 21 s.step = generateState("DBPointer", []byte("inter"), stateConstructor) 22 return scanContinue 23 } 24 return s.error(c, "in literal DBPointer (expecting 'o')") 25} 26 27// Decodes a DBRef literal stored in the underlying byte data into v. 28func (d *decodeState) storeDBPointer(v reflect.Value) { 29 op := d.scanWhile(scanSkipSpace) 30 if op != scanBeginCtor { 31 d.error(fmt.Errorf("expected beginning of constructor")) 32 } 33 34 args := d.ctorInterface() 35 if len(args) != 2 { 36 d.error(fmt.Errorf("expected 2 arguments to DBPointer constructor, but %v received", len(args))) 37 } 38 switch kind := v.Kind(); kind { 39 case reflect.Interface: 40 arg0, ok := args[0].(string) 41 if !ok { 42 d.error(fmt.Errorf("expected first argument to DBPointer to be of type string")) 43 } 44 arg1, ok := args[1].(ObjectId) 45 if !ok { 46 d.error(fmt.Errorf("expected second argument to DBPointer to be of type ObjectId, but ended up being %t", args[1])) 47 } 48 id := bson.ObjectIdHex(string(arg1)) 49 v.Set(reflect.ValueOf(DBPointer{arg0, id})) 50 default: 51 d.error(fmt.Errorf("cannot store %v value into %v type", dbPointerType, kind)) 52 } 53} 54 55// Returns a DBRef literal from the underlying byte data. 56func (d *decodeState) getDBPointer() interface{} { 57 op := d.scanWhile(scanSkipSpace) 58 if op != scanBeginCtor { 59 d.error(fmt.Errorf("expected beginning of constructor")) 60 } 61 62 args := d.ctorInterface() 63 if err := ctorNumArgsMismatch("DBPointer", 2, len(args)); err != nil { 64 d.error(err) 65 } 66 arg0, ok := args[0].(string) 67 if !ok { 68 d.error(fmt.Errorf("expected string for first argument of DBPointer constructor")) 69 } 70 arg1, ok := args[1].(ObjectId) 71 if !ok { 72 d.error(fmt.Errorf("expected ObjectId for second argument of DBPointer constructor")) 73 } 74 id := bson.ObjectIdHex(string(arg1)) 75 76 return DBPointer{arg0, id} 77} 78