| #pragma once |
| |
| #include <boost/algorithm/string/classification.hpp> |
| #include <boost/algorithm/string/constants.hpp> |
| #include <boost/iterator/iterator_facade.hpp> |
| #include <boost/type_index/type_index_facade.hpp> |
| |
| #include <cctype> |
| #include <iomanip> |
| #include <ostream> |
| #include <ranges> |
| #include <span> |
| #include <string> |
| #include <string_view> |
| #include <vector> |
| |
| // IWYU pragma: no_include <ctype.h> |
| |
| namespace http_helpers |
| { |
| |
| enum class ContentType |
| { |
| NoMatch, |
| ANY, // Accepts: */* |
| CBOR, |
| HTML, |
| JSON, |
| OctetStream, |
| EventStream, |
| }; |
| |
| struct ContentTypePair |
| { |
| std::string_view contentTypeString; |
| ContentType contentTypeEnum; |
| }; |
| |
| constexpr std::array<ContentTypePair, 5> contentTypes{{ |
| {"application/cbor", ContentType::CBOR}, |
| {"application/json", ContentType::JSON}, |
| {"application/octet-stream", ContentType::OctetStream}, |
| {"text/html", ContentType::HTML}, |
| {"text/event-stream", ContentType::EventStream}, |
| }}; |
| |
| inline ContentType |
| getPreferredContentType(std::string_view header, |
| std::span<const ContentType> preferedOrder) |
| { |
| size_t lastIndex = 0; |
| while (lastIndex < header.size() + 1) |
| { |
| size_t index = header.find(',', lastIndex); |
| if (index == std::string_view::npos) |
| { |
| index = header.size(); |
| } |
| std::string_view encoding = header.substr(lastIndex, index); |
| |
| if (!header.empty()) |
| { |
| header.remove_prefix(1); |
| } |
| lastIndex = index + 1; |
| // ignore any q-factor weighting (;q=) |
| std::size_t separator = encoding.find(";q="); |
| |
| if (separator != std::string_view::npos) |
| { |
| encoding = encoding.substr(0, separator); |
| } |
| // If the client allows any encoding, given them the first one on the |
| // servers list |
| if (encoding == "*/*") |
| { |
| return ContentType::ANY; |
| } |
| const auto* knownContentType = std::ranges::find_if( |
| contentTypes, [encoding](const ContentTypePair& pair) { |
| return pair.contentTypeString == encoding; |
| }); |
| |
| if (knownContentType == contentTypes.end()) |
| { |
| // not able to find content type in list |
| continue; |
| } |
| |
| // Not one of the types requested |
| if (std::ranges::find(preferedOrder, |
| knownContentType->contentTypeEnum) == |
| preferedOrder.end()) |
| { |
| continue; |
| } |
| return knownContentType->contentTypeEnum; |
| } |
| return ContentType::NoMatch; |
| } |
| |
| inline bool isContentTypeAllowed(std::string_view header, ContentType type, |
| bool allowWildcard) |
| { |
| auto types = std::to_array({type}); |
| ContentType allowed = getPreferredContentType(header, types); |
| if (allowed == ContentType::ANY) |
| { |
| return allowWildcard; |
| } |
| |
| return type == allowed; |
| } |
| |
| } // namespace http_helpers |