1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
#ifndef RFL_CBOR_READER_HPP_
#define RFL_CBOR_READER_HPP_
#include <cstddef>
#include <exception>
#include <jsoncons/json.hpp>
#include <string>
#include <string_view>
#include <type_traits>
#include <vector>
#include "../Bytestring.hpp"
#include "../Result.hpp"
#include "../always_false.hpp"
#include "../internal/ptr_cast.hpp"
namespace rfl::cbor {
class Reader {
public:
struct CBORInputArray {
jsoncons::json* val_;
};
struct CBORInputObject {
jsoncons::json* val_;
};
struct CBORInputVar {
jsoncons::json* val_;
};
using InputArrayType = CBORInputArray;
using InputObjectType = CBORInputObject;
using InputVarType = CBORInputVar;
Reader() {}
~Reader() = default;
template <class T>
static constexpr bool has_custom_constructor =
(requires(InputVarType var) { T::from_cbor_obj(var); });
rfl::Result<InputVarType> get_field_from_array(
const size_t _idx, const InputArrayType& _arr) const noexcept {
if (_idx >= _arr.val_->size()) {
return error("Index out of range.");
}
return InputVarType{&_arr.val_->at(_idx)};
}
rfl::Result<InputVarType> get_field_from_object(
const std::string& _name, const InputObjectType& _obj) const noexcept {
for (auto& kv : _obj.val_->object_range()) {
if (kv.key() == _name) {
return InputVarType{&kv.value()};
};
}
return error("Field name '" + _name + "' not found.");
}
bool is_empty(const InputVarType& _var) const noexcept {
return _var.val_->is_null();
}
template <class T>
rfl::Result<T> to_basic_type(const InputVarType& _var) const noexcept {
if constexpr (std::is_same<std::remove_cvref_t<T>, std::string>()) {
if (!_var.val_->is_string()) {
return error("Could not cast to string.");
}
return _var.val_->as<std::string>();
} else if constexpr (std::is_same<std::remove_cvref_t<T>,
rfl::Bytestring>()) {
if (!_var.val_->is_byte_string()) {
return error("Could not cast to bytestring.");
}
const auto vec = _var.val_->as<std::vector<uint8_t>>();
const auto data = internal::ptr_cast<const std::byte*>(vec.data());
return rfl::Bytestring(data, data + vec.size());
} else if constexpr (std::is_same<std::remove_cvref_t<T>, bool>()) {
if (!_var.val_->is_bool()) {
return error("Could not cast to boolean.");
}
return _var.val_->as<bool>();
} else if constexpr (std::is_floating_point<std::remove_cvref_t<T>>()) {
if (_var.val_->is_double()) {
return static_cast<T>(_var.val_->as<double>());
}
return error("Could not cast to double.");
} else if constexpr (std::is_integral<std::remove_cvref_t<T>>()) {
if (_var.val_->is_int64()) {
return static_cast<T>(_var.val_->as<int64_t>());
}
if (_var.val_->is_uint64()) {
return static_cast<T>(_var.val_->as<uint64_t>());
}
return error("Could not cast to integer.");
} else {
static_assert(rfl::always_false_v<T>, "Unsupported type.");
}
}
rfl::Result<InputArrayType> to_array(
const InputVarType& _var) const noexcept {
if (!_var.val_->is_array()) {
return error("Could not cast to an array.");
}
return InputArrayType{_var.val_};
}
rfl::Result<InputObjectType> to_object(
const InputVarType& _var) const noexcept {
if (!_var.val_->is_object()) {
return error("Could not cast to an object.");
}
return InputObjectType{_var.val_};
}
template <class ArrayReader>
std::optional<Error> read_array(const ArrayReader& _array_reader,
const InputArrayType& _arr) const noexcept {
for (auto& val : _arr.val_->array_range()) {
const auto err = _array_reader.read(InputVarType{&val});
if (err) {
return err;
}
}
return std::nullopt;
}
template <class ObjectReader>
std::optional<Error> read_object(const ObjectReader& _object_reader,
const InputObjectType& _obj) const noexcept {
for (auto& kv : _obj.val_->object_range()) {
_object_reader.read(kv.key(), InputVarType{&kv.value()});
}
return std::nullopt;
}
template <class T>
rfl::Result<T> use_custom_constructor(
const InputVarType& _var) const noexcept {
try {
return T::from_cbor_obj(_var);
} catch (std::exception& e) {
return error(e.what());
}
}
};
} // namespace rfl::cbor
#endif
|
