Files
boost_beast/include/beast/http/fields.hpp
T
Vinnie Falco 9a585a82d9 Refactor treatment of request-method (API Change):
fix #397

method enum class is added to represent all known request methods.
Functions are provided to convert from strings to and from the method
enumeration.

The fields container is modified to also work with the enum.
2017-05-30 15:59:50 -07:00

336 lines
8.1 KiB
C++

//
// Copyright (c) 2013-2017 Vinnie Falco (vinnie dot falco at gmail dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#ifndef BEAST_HTTP_FIELDS_HPP
#define BEAST_HTTP_FIELDS_HPP
#include <beast/config.hpp>
#include <beast/core/string_view.hpp>
#include <beast/core/detail/empty_base_optimization.hpp>
#include <beast/http/verb.hpp>
#include <beast/http/detail/fields.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/optional.hpp>
#include <algorithm>
#include <cctype>
#include <memory>
#include <string>
#include <type_traits>
#include <utility>
namespace beast {
namespace http {
/** A container for storing HTTP header fields.
This container is designed to store the field value pairs that make
up the fields and trailers in an HTTP message. Objects of this type
are iterable, with each element holding the field name and field
value.
Field names are stored as-is, but comparisons are case-insensitive.
When the container is iterated, the fields are presented in the order
of insertion. For fields with the same name, the container behaves
as a `std::multiset`; there will be a separate value for each occurrence
of the field name.
@note Meets the requirements of @b FieldSequence.
*/
template<class Allocator>
class basic_fields :
#if ! BEAST_DOXYGEN
private beast::detail::empty_base_optimization<
typename std::allocator_traits<Allocator>::
template rebind_alloc<
detail::basic_fields_base::element>>,
#endif
public detail::basic_fields_base
{
using alloc_type = typename
std::allocator_traits<Allocator>::
template rebind_alloc<
detail::basic_fields_base::element>;
using alloc_traits =
std::allocator_traits<alloc_type>;
using size_type =
typename std::allocator_traits<Allocator>::size_type;
boost::optional<verb> verb_;
void
delete_all();
void
move_assign(basic_fields&, std::false_type);
void
move_assign(basic_fields&, std::true_type);
void
copy_assign(basic_fields const&, std::false_type);
void
copy_assign(basic_fields const&, std::true_type);
template<class FieldSequence>
void
copy_from(FieldSequence const& fs)
{
for(auto const& e : fs)
insert(e.first, e.second);
}
public:
/// The type of allocator used.
using allocator_type = Allocator;
/** The value type of the field sequence.
Meets the requirements of @b Field.
*/
#if BEAST_DOXYGEN
using value_type = implementation_defined;
#endif
/// A const iterator to the field sequence
#if BEAST_DOXYGEN
using iterator = implementation_defined;
#endif
/// A const iterator to the field sequence
#if BEAST_DOXYGEN
using const_iterator = implementation_defined;
#endif
/// Default constructor.
basic_fields() = default;
/// Destructor
~basic_fields();
/** Construct the fields.
@param alloc The allocator to use.
*/
explicit
basic_fields(Allocator const& alloc);
/** Move constructor.
The moved-from object becomes an empty field sequence.
@param other The object to move from.
*/
basic_fields(basic_fields&& other);
/** Move assignment.
The moved-from object becomes an empty field sequence.
@param other The object to move from.
*/
basic_fields& operator=(basic_fields&& other);
/// Copy constructor.
basic_fields(basic_fields const&);
/// Copy assignment.
basic_fields& operator=(basic_fields const&);
/// Copy constructor.
template<class OtherAlloc>
basic_fields(basic_fields<OtherAlloc> const&);
/// Copy assignment.
template<class OtherAlloc>
basic_fields& operator=(basic_fields<OtherAlloc> const&);
/// Returns a const iterator to the beginning of the field sequence.
const_iterator
begin() const
{
return list_.cbegin();
}
/// Returns a const iterator to the end of the field sequence.
const_iterator
end() const
{
return list_.cend();
}
/// Returns a const iterator to the beginning of the field sequence.
const_iterator
cbegin() const
{
return list_.cbegin();
}
/// Returns a const iterator to the end of the field sequence.
const_iterator
cend() const
{
return list_.cend();
}
/// Returns `true` if the specified field exists.
bool
exists(string_view const& name) const
{
return set_.find(name, less{}) != set_.end();
}
/// Returns the number of values for the specified field.
std::size_t
count(string_view const& name) const;
/** Returns an iterator to the case-insensitive matching field name.
If more than one field with the specified name exists, the
first field defined by insertion order is returned.
*/
iterator
find(string_view const& name) const;
/** Returns the value for a case-insensitive matching header, or `""`.
If more than one field with the specified name exists, the
first field defined by insertion order is returned.
*/
string_view const
operator[](string_view const& name) const;
/// Clear the contents of the basic_fields.
void
clear() noexcept;
/** Remove a field.
If more than one field with the specified name exists, all
matching fields will be removed.
@param name The name of the field(s) to remove.
@return The number of fields removed.
*/
std::size_t
erase(string_view const& name);
/** Insert a field value.
If a field with the same name already exists, the
existing field is untouched and a new field value pair
is inserted into the container.
@param name The name of the field.
@param value A string holding the value of the field.
*/
void
insert(string_view const& name, string_view value);
/** Insert a field value.
If a field with the same name already exists, the
existing field is untouched and a new field value pair
is inserted into the container.
@param name The name of the field
@param value The value of the field. The object will be
converted to a string using `boost::lexical_cast`.
*/
template<class T>
typename std::enable_if<
! std::is_constructible<string_view, T>::value>::type
insert(string_view name, T const& value)
{
insert(name, boost::lexical_cast<std::string>(value));
}
/** Replace a field value.
First removes any values with matching field names, then
inserts the new field value.
@param name The name of the field.
@param value A string holding the value of the field.
*/
void
replace(string_view const& name, string_view value);
/** Replace a field value.
First removes any values with matching field names, then
inserts the new field value.
@param name The name of the field
@param value The value of the field. The object will be
converted to a string using `boost::lexical_cast`.
*/
template<class T>
typename std::enable_if<
! std::is_constructible<string_view, T>::value>::type
replace(string_view const& name, T const& value)
{
replace(name,
boost::lexical_cast<std::string>(value));
}
#if BEAST_DOXYGEN
private:
#endif
string_view
method() const;
void
method(verb v);
void
method(string_view const& s);
string_view
target() const
{
return (*this)[":target"];
}
void
target(string_view const& s)
{
return this->replace(":target", s);
}
string_view
reason() const
{
return (*this)[":reason"];
}
void
reason(string_view const& s)
{
return this->replace(":reason", s);
}
};
/// A typical HTTP header fields container
using fields =
basic_fields<std::allocator<char>>;
} // http
} // beast
#include <beast/http/impl/fields.ipp>
#endif