samples/multipart_service/main.cpp

#include <userver/utest/using_namespace_userver.hpp>
 
#include <userver/components/minimal_server_component_list.hpp>
#include <userver/http/common_headers.hpp>
#include <userver/server/handlers/http_handler_base.hpp>
#include <userver/utils/daemon_run.hpp>
 
namespace samples {

class Multipart final : public server::handlers::HttpHandlerBase {
public:
    // `kName` is used as the component name in static config
    static constexpr std::string_view kName = "handler-multipart-sample";
 
    // Component is valid after construction and is able to accept requests
    using HttpHandlerBase::HttpHandlerBase;
 
    std::string HandleRequest(server::http::HttpRequest& req, server::request::RequestContext&) const override;
};

std::string Multipart::HandleRequest(server::http::HttpRequest& req, server::request::RequestContext&) const {
    const auto content_type = http::ContentType(req.GetHeader(http::headers::kContentType));
    if (content_type != "multipart/form-data") {
        req.GetHttpResponse().SetStatus(server::http::HttpStatus::kBadRequest);
        return "Expected 'multipart/form-data' content type";
    }
 
    const auto& image = req.GetFormDataArg("profileImage");
    static constexpr std::string_view kPngMagicBytes = "\x89PNG\r\n\x1a\n";
    if (!image.value.starts_with(kPngMagicBytes)) {
        req.GetHttpResponse().SetStatus(server::http::HttpStatus::kBadRequest);
        return "Expecting PNG image format";
    }
 
    req.GetHttpResponse().SetContentType(http::content_type::kApplicationJson);
    const auto& address = req.GetFormDataArg("address");
    auto json_addr = formats::json::FromString(address.value);
 
    return fmt::format("city={} image_size={}", json_addr["city"].As<std::string>(), image.value.size());
}
 
}  // namespace samples

int main(int argc, char* argv[]) {
    const auto component_list = components::MinimalServerComponentList().Append<samples::Multipart>();
    return utils::DaemonMain(argc, argv, component_list);
}