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Merge branch 'develop' into feature/issue239
This commit is contained in:
Niels
@ -3595,121 +3595,6 @@ class basic_json
|
||||
}
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Uses a JSON pointer to retrieve a reference to the respective JSON value.
|
||||
No bound checking is performed. Similar to
|
||||
@ref operator[](const typename object_t::key_type&), `null` values
|
||||
are created in arrays and objects if necessary.
|
||||
|
||||
In particular:
|
||||
- If the JSON pointer points to an object key that does not exist, it
|
||||
is created an filled with a `null` value before a reference to it
|
||||
is returned.
|
||||
- If the JSON pointer points to an array index that does not exist, it
|
||||
is created an filled with a `null` value before a reference to it
|
||||
is returned. All indices between the current maximum and the given
|
||||
index are also filled with `null`.
|
||||
- The special value `-` is treated as a synonym for the index past the
|
||||
end.
|
||||
|
||||
@param[in] ptr a JSON pointer
|
||||
|
||||
@return reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,operatorjson_pointer}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
reference operator[](const json_pointer& ptr)
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||||
{
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||||
return ptr.get_unchecked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Uses a JSON pointer to retrieve a reference to the respective JSON value.
|
||||
No bound checking is performed. The function does not change the JSON
|
||||
value; no `null` values are created. In particular, the the special value
|
||||
`-` yields an exception.
|
||||
|
||||
@param[in] ptr JSON pointer to the desired element
|
||||
|
||||
@return const reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,operatorjson_pointer_const}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
const_reference operator[](const json_pointer& ptr) const
|
||||
{
|
||||
return ptr.get_unchecked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Returns a reference to the element at with specified JSON pointer @a ptr,
|
||||
with bounds checking.
|
||||
|
||||
@param[in] ptr JSON pointer to the desired element
|
||||
|
||||
@return reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,at_json_pointer}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
reference at(const json_pointer& ptr)
|
||||
{
|
||||
return ptr.get_checked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Returns a const reference to the element at with specified JSON pointer
|
||||
@a ptr, with bounds checking.
|
||||
|
||||
@param[in] ptr JSON pointer to the desired element
|
||||
|
||||
@return reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,at_json_pointer_const}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
const_reference at(const json_pointer& ptr) const
|
||||
{
|
||||
return ptr.get_checked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified object element with default value
|
||||
|
||||
@ -4145,8 +4030,8 @@ class basic_json
|
||||
|
||||
@throw std::domain_error when called on a type other than JSON array;
|
||||
example: `"cannot use erase() with null"`
|
||||
@throw std::out_of_range when `idx >= size()`; example: `"index out of
|
||||
range"`
|
||||
@throw std::out_of_range when `idx >= size()`; example: `"array index 17
|
||||
is out of range"`
|
||||
|
||||
@complexity Linear in distance between @a idx and the end of the container.
|
||||
|
||||
@ -4167,7 +4052,7 @@ class basic_json
|
||||
{
|
||||
if (idx >= size())
|
||||
{
|
||||
throw std::out_of_range("index out of range");
|
||||
throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
|
||||
}
|
||||
|
||||
assert(m_value.array != nullptr);
|
||||
@ -7875,10 +7760,6 @@ class basic_json
|
||||
{
|
||||
type = value_t::number_unsigned;
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||||
max = static_cast<uint64_t>(std::numeric_limits<number_unsigned_t>::max());
|
||||
if (*curptr == '+')
|
||||
{
|
||||
curptr++;
|
||||
}
|
||||
}
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||||
|
||||
// count the significant figures
|
||||
@ -8245,6 +8126,10 @@ class basic_json
|
||||
/*!
|
||||
@brief JSON Pointer
|
||||
|
||||
A JSON pointer defines a string syntax for identifying a specific value
|
||||
within a JSON document. It can be used with functions `at` and
|
||||
`operator[]`. Furthermore, JSON pointers are the base for JSON patches.
|
||||
|
||||
@sa [RFC 6901](https://tools.ietf.org/html/rfc6901)
|
||||
|
||||
@since version 2.0.0
|
||||
@ -8281,7 +8166,71 @@ class basic_json
|
||||
: reference_tokens(split(s))
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{}
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||||
|
||||
/*!
|
||||
@brief return a string representation of the JSON pointer
|
||||
|
||||
@invariant For each JSON pointer `ptr`, it holds:
|
||||
@code {.cpp}
|
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ptr == json_pointer(ptr.to_string());
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||||
@endcode
|
||||
|
||||
@return a string representation of the JSON pointer
|
||||
|
||||
@liveexample{The example shows the result of `to_string`.,
|
||||
json_pointer__to_string}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
std::string to_string() const noexcept
|
||||
{
|
||||
std::string result;
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||||
|
||||
for (const auto& reference_token : reference_tokens)
|
||||
{
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||||
result += "/" + escape(reference_token);
|
||||
}
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
/// @copydoc to_string()
|
||||
operator std::string() const
|
||||
{
|
||||
return to_string();
|
||||
}
|
||||
|
||||
private:
|
||||
/// remove and return last reference pointer
|
||||
std::string pop_back()
|
||||
{
|
||||
if (is_root())
|
||||
{
|
||||
throw std::domain_error("JSON pointer has no parent");
|
||||
}
|
||||
|
||||
auto last = reference_tokens.back();
|
||||
reference_tokens.pop_back();
|
||||
return last;
|
||||
}
|
||||
|
||||
/// return whether pointer points to the root document
|
||||
bool is_root() const
|
||||
{
|
||||
return reference_tokens.empty();
|
||||
}
|
||||
|
||||
json_pointer top() const
|
||||
{
|
||||
if (is_root())
|
||||
{
|
||||
throw std::domain_error("JSON pointer has no parent");
|
||||
}
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||||
|
||||
json_pointer result = *this;
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||||
result.reference_tokens = {reference_tokens[0]};
|
||||
return result;
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief create and return a reference to the pointed to value
|
||||
*/
|
||||
@ -8320,7 +8269,7 @@ class basic_json
|
||||
case value_t::array:
|
||||
{
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||||
// create an entry in the array
|
||||
result = &result->operator[](static_cast<size_t>(std::stoi(reference_token)));
|
||||
result = &result->operator[](static_cast<size_type>(std::stoi(reference_token)));
|
||||
break;
|
||||
}
|
||||
|
||||
@ -8383,7 +8332,7 @@ class basic_json
|
||||
else
|
||||
{
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||||
// convert array index to number; unchecked access
|
||||
ptr = &ptr->operator[](static_cast<size_t>(std::stoi(reference_token)));
|
||||
ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token)));
|
||||
}
|
||||
break;
|
||||
}
|
||||
@ -8428,7 +8377,7 @@ class basic_json
|
||||
}
|
||||
|
||||
// note: at performs range check
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||||
ptr = &ptr->at(static_cast<size_t>(std::stoi(reference_token)));
|
||||
ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token)));
|
||||
break;
|
||||
}
|
||||
|
||||
@ -8480,7 +8429,7 @@ class basic_json
|
||||
}
|
||||
|
||||
// use unchecked array access
|
||||
ptr = &ptr->operator[](static_cast<size_t>(std::stoi(reference_token)));
|
||||
ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token)));
|
||||
break;
|
||||
}
|
||||
|
||||
@ -8524,7 +8473,7 @@ class basic_json
|
||||
}
|
||||
|
||||
// note: at performs range check
|
||||
ptr = &ptr->at(static_cast<size_t>(std::stoi(reference_token)));
|
||||
ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token)));
|
||||
break;
|
||||
}
|
||||
|
||||
@ -8591,12 +8540,8 @@ class basic_json
|
||||
}
|
||||
}
|
||||
|
||||
// first transform any occurrence of the sequence '~1' to '/'
|
||||
replace_substring(reference_token, "~1", "/");
|
||||
// then transform any occurrence of the sequence '~0' to '~'
|
||||
replace_substring(reference_token, "~0", "~");
|
||||
|
||||
// finally, store the reference token
|
||||
unescape(reference_token);
|
||||
result.push_back(reference_token);
|
||||
}
|
||||
|
||||
@ -8632,6 +8577,24 @@ class basic_json
|
||||
);
|
||||
}
|
||||
|
||||
/// escape tilde and slash
|
||||
static std::string escape(std::string s)
|
||||
{
|
||||
// escape "~"" to "~0" and "/" to "~1"
|
||||
replace_substring(s, "~", "~0");
|
||||
replace_substring(s, "/", "~1");
|
||||
return s;
|
||||
}
|
||||
|
||||
/// unescape tilde and slash
|
||||
static void unescape(std::string& s)
|
||||
{
|
||||
// first transform any occurrence of the sequence '~1' to '/'
|
||||
replace_substring(s, "~1", "/");
|
||||
// then transform any occurrence of the sequence '~0' to '~'
|
||||
replace_substring(s, "~0", "~");
|
||||
}
|
||||
|
||||
/*!
|
||||
@param[in] reference_string the reference string to the current value
|
||||
@param[in] value the value to consider
|
||||
@ -8639,7 +8602,7 @@ class basic_json
|
||||
|
||||
@note Empty objects or arrays are flattened to `null`.
|
||||
*/
|
||||
static void flatten(const std::string reference_string,
|
||||
static void flatten(const std::string& reference_string,
|
||||
const basic_json& value,
|
||||
basic_json& result)
|
||||
{
|
||||
@ -8676,12 +8639,7 @@ class basic_json
|
||||
// iterate object and use keys as reference string
|
||||
for (const auto& element : *value.m_value.object)
|
||||
{
|
||||
// escape "~"" to "~0" and "/" to "~1"
|
||||
std::string key(element.first);
|
||||
replace_substring(key, "~", "~0");
|
||||
replace_substring(key, "/", "~1");
|
||||
|
||||
flatten(reference_string + "/" + key,
|
||||
flatten(reference_string + "/" + escape(element.first),
|
||||
element.second, result);
|
||||
}
|
||||
}
|
||||
@ -8732,16 +8690,131 @@ class basic_json
|
||||
|
||||
private:
|
||||
/// the reference tokens
|
||||
const std::vector<std::string> reference_tokens {};
|
||||
std::vector<std::string> reference_tokens {};
|
||||
};
|
||||
|
||||
////////////////////////////
|
||||
// JSON Pointer functions //
|
||||
////////////////////////////
|
||||
//////////////////////////
|
||||
// JSON Pointer support //
|
||||
//////////////////////////
|
||||
|
||||
/// @name JSON Pointer functions
|
||||
/// @{
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Uses a JSON pointer to retrieve a reference to the respective JSON value.
|
||||
No bound checking is performed. Similar to
|
||||
@ref operator[](const typename object_t::key_type&), `null` values
|
||||
are created in arrays and objects if necessary.
|
||||
|
||||
In particular:
|
||||
- If the JSON pointer points to an object key that does not exist, it
|
||||
is created an filled with a `null` value before a reference to it
|
||||
is returned.
|
||||
- If the JSON pointer points to an array index that does not exist, it
|
||||
is created an filled with a `null` value before a reference to it
|
||||
is returned. All indices between the current maximum and the given
|
||||
index are also filled with `null`.
|
||||
- The special value `-` is treated as a synonym for the index past the
|
||||
end.
|
||||
|
||||
@param[in] ptr a JSON pointer
|
||||
|
||||
@return reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,operatorjson_pointer}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
reference operator[](const json_pointer& ptr)
|
||||
{
|
||||
return ptr.get_unchecked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Uses a JSON pointer to retrieve a reference to the respective JSON value.
|
||||
No bound checking is performed. The function does not change the JSON
|
||||
value; no `null` values are created. In particular, the the special value
|
||||
`-` yields an exception.
|
||||
|
||||
@param[in] ptr JSON pointer to the desired element
|
||||
|
||||
@return const reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,operatorjson_pointer_const}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
const_reference operator[](const json_pointer& ptr) const
|
||||
{
|
||||
return ptr.get_unchecked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Returns a reference to the element at with specified JSON pointer @a ptr,
|
||||
with bounds checking.
|
||||
|
||||
@param[in] ptr JSON pointer to the desired element
|
||||
|
||||
@return reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,at_json_pointer}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
reference at(const json_pointer& ptr)
|
||||
{
|
||||
return ptr.get_checked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief access specified element via JSON Pointer
|
||||
|
||||
Returns a const reference to the element at with specified JSON pointer
|
||||
@a ptr, with bounds checking.
|
||||
|
||||
@param[in] ptr JSON pointer to the desired element
|
||||
|
||||
@return reference to the element pointed to by @a ptr
|
||||
|
||||
@complexity Constant.
|
||||
|
||||
@throw std::out_of_range if the JSON pointer can not be resolved
|
||||
@throw std::domain_error if an array index begins with '0'
|
||||
@throw std::invalid_argument if an array index was not a number
|
||||
|
||||
@liveexample{The behavior is shown in the example.,at_json_pointer_const}
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
const_reference at(const json_pointer& ptr) const
|
||||
{
|
||||
return ptr.get_checked(this);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief return flattened JSON value
|
||||
|
||||
@ -8804,6 +8877,473 @@ class basic_json
|
||||
}
|
||||
|
||||
/// @}
|
||||
|
||||
//////////////////////////
|
||||
// JSON Patch functions //
|
||||
//////////////////////////
|
||||
|
||||
/// @name JSON Patch functions
|
||||
/// @{
|
||||
|
||||
/*!
|
||||
@brief applies a JSON patch
|
||||
|
||||
[JSON Patch](http://jsonpatch.com) defines a JSON document structure for
|
||||
expressing a sequence of operations to apply to a JSON) document. With
|
||||
this funcion, a JSON Patch is applied to the current JSON value by
|
||||
executing all operations from the patch.
|
||||
|
||||
@param[in] patch JSON patch document
|
||||
@return patched document
|
||||
|
||||
@note The application of a patch is atomic: Either all operations succeed
|
||||
and the patched document is returned or an exception is thrown. In
|
||||
any case, the original value is not changed: the patch is applied
|
||||
to a copy of the value.
|
||||
|
||||
@throw std::out_of_range if a JSON pointer inside the patch could not
|
||||
be resolved successfully in the current JSON value; example: `"key baz
|
||||
not found"`
|
||||
@throw invalid_argument if the JSON patch is malformed (e.g., mandatory
|
||||
attributes are missing); example: `"operation add must have member path"`
|
||||
|
||||
@complexity Linear in the size of the JSON value and the length of the
|
||||
JSON patch. As usually only a fraction of the JSON value is affected by
|
||||
the patch, the complexity can usually be neglected.
|
||||
|
||||
@liveexample{The following code shows how a JSON patch is applied to a
|
||||
value.,patch}
|
||||
|
||||
@sa @ref diff -- create a JSON patch by comparing two JSON values
|
||||
|
||||
@sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
|
||||
@sa [RFC 6901 (JSON Pointer)](https://tools.ietf.org/html/rfc6901)
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
basic_json patch(const basic_json& patch) const
|
||||
{
|
||||
// make a working copy to apply the patch to
|
||||
basic_json result = *this;
|
||||
|
||||
// the valid JSON Patch operations
|
||||
enum class patch_operations {add, remove, replace, move, copy, test, invalid};
|
||||
|
||||
const auto get_op = [](const std::string op)
|
||||
{
|
||||
if (op == "add")
|
||||
{
|
||||
return patch_operations::add;
|
||||
}
|
||||
if (op == "remove")
|
||||
{
|
||||
return patch_operations::remove;
|
||||
}
|
||||
if (op == "replace")
|
||||
{
|
||||
return patch_operations::replace;
|
||||
}
|
||||
if (op == "move")
|
||||
{
|
||||
return patch_operations::move;
|
||||
}
|
||||
if (op == "copy")
|
||||
{
|
||||
return patch_operations::copy;
|
||||
}
|
||||
if (op == "test")
|
||||
{
|
||||
return patch_operations::test;
|
||||
}
|
||||
|
||||
return patch_operations::invalid;
|
||||
};
|
||||
|
||||
// wrapper for "add" operation; add value at ptr
|
||||
const auto operation_add = [&result](json_pointer & ptr, basic_json val)
|
||||
{
|
||||
// adding to the root of the target document means replacing it
|
||||
if (ptr.is_root())
|
||||
{
|
||||
result = val;
|
||||
}
|
||||
else
|
||||
{
|
||||
// make sure the top element of the pointer exists
|
||||
json_pointer top_pointer = ptr.top();
|
||||
if (top_pointer != ptr)
|
||||
{
|
||||
basic_json& x = result.at(top_pointer);
|
||||
}
|
||||
|
||||
// get reference to parent of JSON pointer ptr
|
||||
const auto last_path = ptr.pop_back();
|
||||
basic_json& parent = result[ptr];
|
||||
|
||||
switch (parent.m_type)
|
||||
{
|
||||
case value_t::null:
|
||||
case value_t::object:
|
||||
{
|
||||
// use operator[] to add value
|
||||
parent[last_path] = val;
|
||||
break;
|
||||
}
|
||||
|
||||
case value_t::array:
|
||||
{
|
||||
if (last_path == "-")
|
||||
{
|
||||
// special case: append to back
|
||||
parent.push_back(val);
|
||||
}
|
||||
else
|
||||
{
|
||||
const auto idx = std::stoi(last_path);
|
||||
if (static_cast<size_type>(idx) > parent.size())
|
||||
{
|
||||
// avoid undefined behavior
|
||||
throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
|
||||
}
|
||||
else
|
||||
{
|
||||
// default case: insert add offset
|
||||
parent.insert(parent.begin() + static_cast<difference_type>(idx), val);
|
||||
}
|
||||
}
|
||||
break;
|
||||
}
|
||||
|
||||
default:
|
||||
{
|
||||
// if there exists a parent it cannot be primitive
|
||||
assert(false); // LCOV_EXCL_LINE
|
||||
}
|
||||
}
|
||||
}
|
||||
};
|
||||
|
||||
// wrapper for "remove" operation; remove value at ptr
|
||||
const auto operation_remove = [&result](json_pointer & ptr)
|
||||
{
|
||||
// get reference to parent of JSON pointer ptr
|
||||
const auto last_path = ptr.pop_back();
|
||||
basic_json& parent = result.at(ptr);
|
||||
|
||||
// remove child
|
||||
if (parent.is_object())
|
||||
{
|
||||
// perform range check
|
||||
auto it = parent.find(last_path);
|
||||
if (it != parent.end())
|
||||
{
|
||||
parent.erase(it);
|
||||
}
|
||||
else
|
||||
{
|
||||
throw std::out_of_range("key '" + last_path + "' not found");
|
||||
}
|
||||
}
|
||||
else if (parent.is_array())
|
||||
{
|
||||
// note erase performs range check
|
||||
parent.erase(static_cast<size_type>(std::stoi(last_path)));
|
||||
}
|
||||
};
|
||||
|
||||
// type check
|
||||
if (not patch.is_array())
|
||||
{
|
||||
// a JSON patch must be an array of objects
|
||||
throw std::invalid_argument("JSON patch must be an array of objects");
|
||||
}
|
||||
|
||||
// iterate and apply th eoperations
|
||||
for (const auto& val : patch)
|
||||
{
|
||||
// wrapper to get a value for an operation
|
||||
const auto get_value = [&val](const std::string & op,
|
||||
const std::string & member,
|
||||
bool string_type) -> basic_json&
|
||||
{
|
||||
// find value
|
||||
auto it = val.m_value.object->find(member);
|
||||
|
||||
// context-sensitive error message
|
||||
const auto error_msg = (op == "op") ? "operation" : "operation '" + op + "'";
|
||||
|
||||
// check if desired value is present
|
||||
if (it == val.m_value.object->end())
|
||||
{
|
||||
throw std::invalid_argument(error_msg + " must have member '" + member + "'");
|
||||
}
|
||||
|
||||
// check if result is of type string
|
||||
if (string_type and not it->second.is_string())
|
||||
{
|
||||
throw std::invalid_argument(error_msg + " must have string member '" + member + "'");
|
||||
}
|
||||
|
||||
// no error: return value
|
||||
return it->second;
|
||||
};
|
||||
|
||||
// type check
|
||||
if (not val.is_object())
|
||||
{
|
||||
throw std::invalid_argument("JSON patch must be an array of objects");
|
||||
}
|
||||
|
||||
// collect mandatory members
|
||||
const std::string op = get_value("op", "op", true);
|
||||
const std::string path = get_value(op, "path", true);
|
||||
json_pointer ptr(path);
|
||||
|
||||
switch (get_op(op))
|
||||
{
|
||||
case patch_operations::add:
|
||||
{
|
||||
operation_add(ptr, get_value("add", "value", false));
|
||||
break;
|
||||
}
|
||||
|
||||
case patch_operations::remove:
|
||||
{
|
||||
operation_remove(ptr);
|
||||
break;
|
||||
}
|
||||
|
||||
case patch_operations::replace:
|
||||
{
|
||||
// the "path" location must exist - use at()
|
||||
result.at(ptr) = get_value("replace", "value", false);
|
||||
break;
|
||||
}
|
||||
|
||||
case patch_operations::move:
|
||||
{
|
||||
const std::string from_path = get_value("move", "from", true);
|
||||
json_pointer from_ptr(from_path);
|
||||
|
||||
// the "from" location must exist - use at()
|
||||
basic_json v = result.at(from_ptr);
|
||||
|
||||
// The move operation is functionally identical to a
|
||||
// "remove" operation on the "from" location, followed
|
||||
// immediately by an "add" operation at the target
|
||||
// location with the value that was just removed.
|
||||
operation_remove(from_ptr);
|
||||
operation_add(ptr, v);
|
||||
break;
|
||||
}
|
||||
|
||||
case patch_operations::copy:
|
||||
{
|
||||
const std::string from_path = get_value("copy", "from", true);;
|
||||
const json_pointer from_ptr(from_path);
|
||||
|
||||
// the "from" location must exist - use at()
|
||||
result[ptr] = result.at(from_ptr);
|
||||
break;
|
||||
}
|
||||
|
||||
case patch_operations::test:
|
||||
{
|
||||
bool success = false;
|
||||
try
|
||||
{
|
||||
// check if "value" matches the one at "path"
|
||||
// the "path" location must exist - use at()
|
||||
success = (result.at(ptr) == get_value("test", "value", false));
|
||||
}
|
||||
catch (std::out_of_range&)
|
||||
{
|
||||
// ignore out of range errors: success remains false
|
||||
}
|
||||
|
||||
// throw an exception if test fails
|
||||
if (not success)
|
||||
{
|
||||
throw std::domain_error("unsuccessful: " + val.dump());
|
||||
}
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
case patch_operations::invalid:
|
||||
{
|
||||
// op must be "add", "remove", "replace", "move", "copy", or
|
||||
// "test"
|
||||
throw std::invalid_argument("operation value '" + op + "' is invalid");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief creates a diff as a JSON patch
|
||||
|
||||
Creates a [JSON Patch](http://jsonpatch.com) so that value @a source can
|
||||
be changed into the value @a target by calling @ref patch function.
|
||||
|
||||
@invariant For two JSON values @a source and @a target, the following code
|
||||
yields always `true`:
|
||||
@code {.cpp}
|
||||
source.patch(diff(source, target)) == target;
|
||||
@endcode
|
||||
|
||||
@note Currently, only `remove`, `add`, and `replace` operations are
|
||||
generated.
|
||||
|
||||
@param[in] source JSON value to copare from
|
||||
@param[in] target JSON value to copare against
|
||||
@param[in] path helper value to create JSON pointers
|
||||
|
||||
@return a JSON patch to convert the @a source to @a target
|
||||
|
||||
@complexity Linear in the lengths of @a source and @a target.
|
||||
|
||||
@liveexample{The following code shows how a JSON patch is created as a
|
||||
diff for two JSON values.,diff}
|
||||
|
||||
@sa @ref patch -- apply a JSON patch
|
||||
|
||||
@sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
|
||||
|
||||
@since version 2.0.0
|
||||
*/
|
||||
static basic_json diff(const basic_json& source,
|
||||
const basic_json& target,
|
||||
std::string path = "") noexcept
|
||||
{
|
||||
// the patch
|
||||
basic_json result(value_t::array);
|
||||
|
||||
// if the values are the same, return empty patch
|
||||
if (source == target)
|
||||
{
|
||||
return result;
|
||||
}
|
||||
|
||||
if (source.type() != target.type())
|
||||
{
|
||||
// different types: replace value
|
||||
result.push_back(
|
||||
{
|
||||
{"op", "replace"},
|
||||
{"path", path},
|
||||
{"value", target}
|
||||
});
|
||||
}
|
||||
else
|
||||
{
|
||||
switch (source.type())
|
||||
{
|
||||
case value_t::array:
|
||||
{
|
||||
// first pass: traverse common elements
|
||||
size_t i = 0;
|
||||
while (i < source.size() and i < target.size())
|
||||
{
|
||||
// recursive call to compare array values at index i
|
||||
auto temp_diff = diff(source[i], target[i], path + "/" + std::to_string(i));
|
||||
result.insert(result.end(), temp_diff.begin(), temp_diff.end());
|
||||
++i;
|
||||
}
|
||||
|
||||
// i now reached the end of at least one array
|
||||
// in a second pass, traverse the remaining elements
|
||||
|
||||
// remove my remaining elements
|
||||
while (i < source.size())
|
||||
{
|
||||
result.push_back(object(
|
||||
{
|
||||
{"op", "remove"},
|
||||
{"path", path + "/" + std::to_string(i)}
|
||||
}));
|
||||
++i;
|
||||
}
|
||||
|
||||
// add other remaining elements
|
||||
while (i < target.size())
|
||||
{
|
||||
result.push_back(
|
||||
{
|
||||
{"op", "add"},
|
||||
{"path", path + "/" + std::to_string(i)},
|
||||
{"value", target[i]}
|
||||
});
|
||||
++i;
|
||||
}
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
case value_t::object:
|
||||
{
|
||||
// first pass: traverse this object's elements
|
||||
for (auto it = source.begin(); it != source.end(); ++it)
|
||||
{
|
||||
// escape the key name to be used in a JSON patch
|
||||
const auto key = json_pointer::escape(it.key());
|
||||
|
||||
if (target.find(it.key()) != target.end())
|
||||
{
|
||||
// recursive call to compare object values at key it
|
||||
auto temp_diff = diff(it.value(), target[it.key()], path + "/" + key);
|
||||
result.insert(result.end(), temp_diff.begin(), temp_diff.end());
|
||||
}
|
||||
else
|
||||
{
|
||||
// found a key that is not in o -> remove it
|
||||
result.push_back(object(
|
||||
{
|
||||
{"op", "remove"},
|
||||
{"path", path + "/" + key}
|
||||
}));
|
||||
}
|
||||
}
|
||||
|
||||
// second pass: traverse other object's elements
|
||||
for (auto it = target.begin(); it != target.end(); ++it)
|
||||
{
|
||||
if (source.find(it.key()) == source.end())
|
||||
{
|
||||
// found a key that is not in this -> add it
|
||||
const auto key = json_pointer::escape(it.key());
|
||||
result.push_back(
|
||||
{
|
||||
{"op", "add"},
|
||||
{"path", path + "/" + key},
|
||||
{"value", it.value()}
|
||||
});
|
||||
}
|
||||
}
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
default:
|
||||
{
|
||||
// both primitive type: replace value
|
||||
result.push_back(
|
||||
{
|
||||
{"op", "replace"},
|
||||
{"path", path},
|
||||
{"value", target}
|
||||
});
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
/// @}
|
||||
};
|
||||
|
||||
|
||||
@ -8823,9 +9363,9 @@ using json = basic_json<>;
|
||||
}
|
||||
|
||||
|
||||
/////////////////////////
|
||||
// nonmember functions //
|
||||
/////////////////////////
|
||||
///////////////////////
|
||||
// nonmember support //
|
||||
///////////////////////
|
||||
|
||||
// specialization of std::swap, and std::hash
|
||||
namespace std
|
||||
|
||||
Reference in New Issue
Block a user