first commit

ext/crow/routing.h

@@ -0,0 +1,892 @@
+#pragma once
+
+#include <cstdint>
+#include <utility>
+#include <tuple>
+#include <unordered_map>
+#include <memory>
+#include <boost/lexical_cast.hpp>
+#include <vector>
+
+#include "common.h"
+#include "http_response.h"
+#include "http_request.h"
+#include "utility.h"
+#include "logging.h"
+
+namespace crow
+{
+    class BaseRule
+    {
+    public:
+        BaseRule(std::string rule)
+            : rule_(std::move(rule))
+        {
+        }
+
+        virtual ~BaseRule()
+        {
+        }
+        
+        virtual void validate() = 0;
+
+        virtual void handle(const request&, response&, const routing_params&) = 0;
+
+        uint32_t get_methods()
+        {
+            return methods_;
+        }
+
+    protected:
+        uint32_t methods_{1<<(int)HTTPMethod::GET};
+
+        std::string rule_;
+        std::string name_;
+        friend class Router;
+        template <typename T>
+        friend struct RuleParameterTraits;
+    };
+
+
+    namespace detail
+    {
+        namespace routing_handler_call_helper
+        {
+            template <typename T, int Pos>
+            struct call_pair
+            {
+                using type = T;
+                static const int pos = Pos;
+            };
+
+            template <typename H1>
+            struct call_params
+            {
+                H1& handler;
+                const routing_params& params;
+                const request& req;
+                response& res;
+            };
+
+            template <typename F, int NInt, int NUint, int NDouble, int NString, typename S1, typename S2> 
+            struct call
+            {
+            };
+
+            template <typename F, int NInt, int NUint, int NDouble, int NString, typename ... Args1, typename ... Args2> 
+            struct call<F, NInt, NUint, NDouble, NString, black_magic::S<int64_t, Args1...>, black_magic::S<Args2...>>
+            {
+                void operator()(F cparams)
+                {
+                    using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<int64_t, NInt>>;
+                    call<F, NInt+1, NUint, NDouble, NString,
+                        black_magic::S<Args1...>, pushed>()(cparams);
+                }
+            };
+
+            template <typename F, int NInt, int NUint, int NDouble, int NString, typename ... Args1, typename ... Args2> 
+            struct call<F, NInt, NUint, NDouble, NString, black_magic::S<uint64_t, Args1...>, black_magic::S<Args2...>>
+            {
+                void operator()(F cparams)
+                {
+                    using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<uint64_t, NUint>>;
+                    call<F, NInt, NUint+1, NDouble, NString,
+                        black_magic::S<Args1...>, pushed>()(cparams);
+                }
+            };
+
+            template <typename F, int NInt, int NUint, int NDouble, int NString, typename ... Args1, typename ... Args2> 
+            struct call<F, NInt, NUint, NDouble, NString, black_magic::S<double, Args1...>, black_magic::S<Args2...>>
+            {
+                void operator()(F cparams)
+                {
+                    using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<double, NDouble>>;
+                    call<F, NInt, NUint, NDouble+1, NString,
+                        black_magic::S<Args1...>, pushed>()(cparams);
+                }
+            };
+
+            template <typename F, int NInt, int NUint, int NDouble, int NString, typename ... Args1, typename ... Args2> 
+            struct call<F, NInt, NUint, NDouble, NString, black_magic::S<std::string, Args1...>, black_magic::S<Args2...>>
+            {
+                void operator()(F cparams)
+                {
+                    using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<std::string, NString>>;
+                    call<F, NInt, NUint, NDouble, NString+1,
+                        black_magic::S<Args1...>, pushed>()(cparams);
+                }
+            };
+
+            template <typename F, int NInt, int NUint, int NDouble, int NString, typename ... Args1> 
+            struct call<F, NInt, NUint, NDouble, NString, black_magic::S<>, black_magic::S<Args1...>>
+            {
+                void operator()(F cparams)
+                {
+                    cparams.handler(
+                        cparams.req,
+                        cparams.res,
+                        cparams.params.template get<typename Args1::type>(Args1::pos)... 
+                    );
+                }
+            };
+
+            template <typename Func, typename ... ArgsWrapped>
+            struct Wrapped
+            {
+                template <typename ... Args>
+                void set(Func f, typename std::enable_if<
+                    !std::is_same<typename std::tuple_element<0, std::tuple<Args..., void>>::type, const request&>::value
+                , int>::type = 0)
+                {
+                    handler_ = (
+#ifdef CROW_CAN_USE_CPP14
+                        [f = std::move(f)]
+#else
+                        [f]
+#endif
+                        (const request&, response& res, Args... args){
+                            res = response(f(args...));
+                            res.end();
+                        });
+                }
+
+                template <typename Req, typename ... Args>
+                struct req_handler_wrapper
+                {
+                    req_handler_wrapper(Func f)
+                        : f(std::move(f))
+                    {
+                    }
+
+                    void operator()(const request& req, response& res, Args... args)
+                    {
+                        res = response(f(req, args...));
+                        res.end();
+                    }
+
+                    Func f;
+                };
+
+                template <typename ... Args>
+                void set(Func f, typename std::enable_if<
+                        std::is_same<typename std::tuple_element<0, std::tuple<Args..., void>>::type, const request&>::value &&
+                        !std::is_same<typename std::tuple_element<1, std::tuple<Args..., void, void>>::type, response&>::value
+                        , int>::type = 0)
+                {
+                    handler_ = req_handler_wrapper<Args...>(std::move(f));
+                    /*handler_ = (
+                        [f = std::move(f)]
+                        (const request& req, response& res, Args... args){
+                             res = response(f(req, args...));
+                             res.end();
+                        });*/
+                }
+
+                template <typename ... Args>
+                void set(Func f, typename std::enable_if<
+                        std::is_same<typename std::tuple_element<0, std::tuple<Args..., void>>::type, const request&>::value &&
+                        std::is_same<typename std::tuple_element<1, std::tuple<Args..., void, void>>::type, response&>::value
+                        , int>::type = 0)
+                {
+                    handler_ = std::move(f);
+                }
+
+                template <typename ... Args>
+                struct handler_type_helper
+                {
+                    using type = std::function<void(const crow::request&, crow::response&, Args...)>;
+                    using args_type = black_magic::S<typename black_magic::promote_t<Args>...>; 
+                };
+
+                template <typename ... Args>
+                struct handler_type_helper<const request&, Args...>
+                {
+                    using type = std::function<void(const crow::request&, crow::response&, Args...)>;
+                    using args_type = black_magic::S<typename black_magic::promote_t<Args>...>; 
+                };
+
+                template <typename ... Args>
+                struct handler_type_helper<const request&, response&, Args...>
+                {
+                    using type = std::function<void(const crow::request&, crow::response&, Args...)>;
+                    using args_type = black_magic::S<typename black_magic::promote_t<Args>...>; 
+                };
+
+                typename handler_type_helper<ArgsWrapped...>::type handler_;
+
+                void operator()(const request& req, response& res, const routing_params& params)
+                {
+                    detail::routing_handler_call_helper::call<
+                        detail::routing_handler_call_helper::call_params<
+                            decltype(handler_)>,
+                        0, 0, 0, 0, 
+                        typename handler_type_helper<ArgsWrapped...>::args_type,
+                        black_magic::S<>
+                    >()(
+                        detail::routing_handler_call_helper::call_params<
+                            decltype(handler_)>
+                        {handler_, params, req, res}
+                   );
+                }
+            };
+
+        }
+    }
+
+    template <typename T>
+    struct RuleParameterTraits
+    {
+        using self_t = T;
+        self_t& name(std::string name) noexcept
+        {
+            ((self_t*)this)->name_ = std::move(name);
+            return (self_t&)*this;
+        }
+
+        self_t& methods(HTTPMethod method)
+        {
+            ((self_t*)this)->methods_ = 1 << (int)method;
+            return (self_t&)*this;
+        }
+
+        template <typename ... MethodArgs>
+        self_t& methods(HTTPMethod method, MethodArgs ... args_method)
+        {
+            methods(args_method...);
+            ((self_t*)this)->methods_ |= 1 << (int)method;
+            return (self_t&)*this;
+        }
+    };
+
+    class DynamicRule : public BaseRule, public RuleParameterTraits<DynamicRule>
+    {
+    public:
+
+        DynamicRule(std::string rule)
+            : BaseRule(std::move(rule))
+        {
+        }
+
+        void validate() override
+        {
+            if (!erased_handler_)
+            {
+                throw std::runtime_error(name_ + (!name_.empty() ? ": " : "") + "no handler for url " + rule_);
+            }
+        }
+
+        void handle(const request& req, response& res, const routing_params& params) override
+        {
+            erased_handler_(req, res, params);
+        }
+
+        template <typename Func>
+        void operator()(Func f)
+        {
+#ifdef CROW_MSVC_WORKAROUND
+            using function_t = utility::function_traits<decltype(&Func::operator())>;
+#else
+            using function_t = utility::function_traits<Func>;
+#endif
+            erased_handler_ = wrap(std::move(f), black_magic::gen_seq<function_t::arity>());
+        }
+
+        // enable_if Arg1 == request && Arg2 == response
+        // enable_if Arg1 == request && Arg2 != resposne
+        // enable_if Arg1 != request
+#ifdef CROW_MSVC_WORKAROUND
+        template <typename Func, size_t ... Indices>
+#else
+        template <typename Func, unsigned ... Indices>
+#endif
+        std::function<void(const request&, response&, const routing_params&)> 
+        wrap(Func f, black_magic::seq<Indices...>)
+        {
+#ifdef CROW_MSVC_WORKAROUND
+            using function_t = utility::function_traits<decltype(&Func::operator())>;
+#else
+            using function_t = utility::function_traits<Func>;
+#endif
+            if (!black_magic::is_parameter_tag_compatible(
+                black_magic::get_parameter_tag_runtime(rule_.c_str()), 
+                black_magic::compute_parameter_tag_from_args_list<
+                    typename function_t::template arg<Indices>...>::value))
+            {
+                throw std::runtime_error("route_dynamic: Handler type is mismatched with URL parameters: " + rule_);
+            }
+            auto ret = detail::routing_handler_call_helper::Wrapped<Func, typename function_t::template arg<Indices>...>();
+            ret.template set<
+                typename function_t::template arg<Indices>...
+            >(std::move(f));
+            return ret;
+        }
+
+        template <typename Func>
+        void operator()(std::string name, Func&& f)
+        {
+            name_ = std::move(name);
+            (*this).template operator()<Func>(std::forward(f));
+        }
+    private:
+        std::function<void(const request&, response&, const routing_params&)> erased_handler_;
+
+    };
+
+    template <typename ... Args>
+    class TaggedRule : public BaseRule, public RuleParameterTraits<TaggedRule<Args...>>
+    {
+    public:
+        using self_t = TaggedRule<Args...>;
+
+        TaggedRule(std::string rule)
+            : BaseRule(std::move(rule))
+        {
+        }
+
+        void validate()
+        {
+            if (!handler_)
+            {
+                throw std::runtime_error(name_ + (!name_.empty() ? ": " : "") + "no handler for url " + rule_);
+            }
+        }
+
+        template <typename Func>
+        typename std::enable_if<black_magic::CallHelper<Func, black_magic::S<Args...>>::value, void>::type
+        operator()(Func&& f)
+        {
+            static_assert(black_magic::CallHelper<Func, black_magic::S<Args...>>::value ||
+                black_magic::CallHelper<Func, black_magic::S<crow::request, Args...>>::value , 
+                "Handler type is mismatched with URL parameters");
+            static_assert(!std::is_same<void, decltype(f(std::declval<Args>()...))>::value, 
+                "Handler function cannot have void return type; valid return types: string, int, crow::resposne, crow::json::wvalue");
+
+                handler_ = [f = std::move(f)](const request&, response& res, Args ... args){
+                    res = response(f(args...));
+                    res.end();
+                };
+        }
+
+        template <typename Func>
+        typename std::enable_if<
+            !black_magic::CallHelper<Func, black_magic::S<Args...>>::value &&
+            black_magic::CallHelper<Func, black_magic::S<crow::request, Args...>>::value, 
+            void>::type
+        operator()(Func&& f)
+        {
+            static_assert(black_magic::CallHelper<Func, black_magic::S<Args...>>::value ||
+                black_magic::CallHelper<Func, black_magic::S<crow::request, Args...>>::value, 
+                "Handler type is mismatched with URL parameters");
+            static_assert(!std::is_same<void, decltype(f(std::declval<crow::request>(), std::declval<Args>()...))>::value, 
+                "Handler function cannot have void return type; valid return types: string, int, crow::resposne, crow::json::wvalue");
+
+                handler_ = [f = std::move(f)](const crow::request& req, crow::response& res, Args ... args){
+                    res = response(f(req, args...));
+                    res.end();
+                };
+        }
+
+        template <typename Func>
+        typename std::enable_if<
+            !black_magic::CallHelper<Func, black_magic::S<Args...>>::value &&
+            !black_magic::CallHelper<Func, black_magic::S<crow::request, Args...>>::value, 
+            void>::type
+        operator()(Func&& f)
+        {
+            static_assert(black_magic::CallHelper<Func, black_magic::S<Args...>>::value ||
+                black_magic::CallHelper<Func, black_magic::S<crow::request, Args...>>::value ||
+                black_magic::CallHelper<Func, black_magic::S<crow::request, crow::response&, Args...>>::value
+                , 
+                "Handler type is mismatched with URL parameters");
+            static_assert(std::is_same<void, decltype(f(std::declval<crow::request>(), std::declval<crow::response&>(), std::declval<Args>()...))>::value, 
+                "Handler function with response argument should have void return type");
+
+                handler_ = std::move(f);
+        }
+
+        template <typename Func>
+        void operator()(std::string name, Func&& f)
+        {
+            name_ = std::move(name);
+            (*this).template operator()<Func>(std::forward(f));
+        }
+
+        void handle(const request& req, response& res, const routing_params& params) override
+        {
+            detail::routing_handler_call_helper::call<
+                detail::routing_handler_call_helper::call_params<
+                    decltype(handler_)>, 
+                0, 0, 0, 0, 
+                black_magic::S<Args...>, 
+                black_magic::S<>
+            >()(
+                detail::routing_handler_call_helper::call_params<
+                    decltype(handler_)>
+                {handler_, params, req, res}
+            );
+        }
+
+    private:
+        std::function<void(const crow::request&, crow::response&, Args...)> handler_;
+
+    };
+
+    const int RULE_SPECIAL_REDIRECT_SLASH = 1;
+
+    class Trie
+    {
+    public:
+        struct Node
+        {
+            unsigned rule_index{};
+            std::array<unsigned, (int)ParamType::MAX> param_childrens{};
+            std::unordered_map<std::string, unsigned> children;
+
+            bool IsSimpleNode() const
+            {
+                return 
+                    !rule_index &&
+                    std::all_of(
+                        std::begin(param_childrens), 
+                        std::end(param_childrens), 
+                        [](unsigned x){ return !x; });
+            }
+        };
+
+        Trie() : nodes_(1)
+        {
+        }
+
+private:
+        void optimizeNode(Node* node)
+        {
+            for(auto x : node->param_childrens)
+            {
+                if (!x)
+                    continue;
+                Node* child = &nodes_[x];
+                optimizeNode(child);
+            }
+            if (node->children.empty())
+                return;
+            bool mergeWithChild = true;
+            for(auto& kv : node->children)
+            {
+                Node* child = &nodes_[kv.second];
+                if (!child->IsSimpleNode())
+                {
+                    mergeWithChild = false;
+                    break;
+                }
+            }
+            if (mergeWithChild)
+            {
+                decltype(node->children) merged;
+                for(auto& kv : node->children)
+                {
+                    Node* child = &nodes_[kv.second];
+                    for(auto& child_kv : child->children)
+                    {
+                        merged[kv.first + child_kv.first] = child_kv.second;
+                    }
+                }
+                node->children = std::move(merged);
+                optimizeNode(node);
+            }
+            else
+            {
+                for(auto& kv : node->children)
+                {
+                    Node* child = &nodes_[kv.second];
+                    optimizeNode(child);
+                }
+            }
+        }
+
+        void optimize()
+        {
+            optimizeNode(head());
+        }
+
+public:
+        void validate()
+        {
+            if (!head()->IsSimpleNode())
+                throw std::runtime_error("Internal error: Trie header should be simple!");
+            optimize();
+        }
+
+        std::pair<unsigned, routing_params> find(const std::string& req_url, const Node* node = nullptr, unsigned pos = 0, routing_params* params = nullptr) const
+        {
+            routing_params empty;
+            if (params == nullptr)
+                params = &empty;
+
+            unsigned found{};
+            routing_params match_params;
+
+            if (node == nullptr)
+                node = head();
+            if (pos == req_url.size())
+                return {node->rule_index, *params};
+
+            auto update_found = [&found, &match_params](std::pair<unsigned, routing_params>& ret)
+            {
+                if (ret.first && (!found || found > ret.first))
+                {
+                    found = ret.first;
+                    match_params = std::move(ret.second);
+                }
+            };
+
+            if (node->param_childrens[(int)ParamType::INT])
+            {
+                char c = req_url[pos];
+                if ((c >= '0' && c <= '9') || c == '+' || c == '-')
+                {
+                    char* eptr;
+                    errno = 0;
+                    long long int value = strtoll(req_url.data()+pos, &eptr, 10);
+                    if (errno != ERANGE && eptr != req_url.data()+pos)
+                    {
+                        params->int_params.push_back(value);
+                        auto ret = find(req_url, &nodes_[node->param_childrens[(int)ParamType::INT]], eptr - req_url.data(), params);
+                        update_found(ret);
+                        params->int_params.pop_back();
+                    }
+                }
+            }
+
+            if (node->param_childrens[(int)ParamType::UINT])
+            {
+                char c = req_url[pos];
+                if ((c >= '0' && c <= '9') || c == '+')
+                {
+                    char* eptr;
+                    errno = 0;
+                    unsigned long long int value = strtoull(req_url.data()+pos, &eptr, 10);
+                    if (errno != ERANGE && eptr != req_url.data()+pos)
+                    {
+                        params->uint_params.push_back(value);
+                        auto ret = find(req_url, &nodes_[node->param_childrens[(int)ParamType::UINT]], eptr - req_url.data(), params);
+                        update_found(ret);
+                        params->uint_params.pop_back();
+                    }
+                }
+            }
+
+            if (node->param_childrens[(int)ParamType::DOUBLE])
+            {
+                char c = req_url[pos];
+                if ((c >= '0' && c <= '9') || c == '+' || c == '-' || c == '.')
+                {
+                    char* eptr;
+                    errno = 0;
+                    double value = strtod(req_url.data()+pos, &eptr);
+                    if (errno != ERANGE && eptr != req_url.data()+pos)
+                    {
+                        params->double_params.push_back(value);
+                        auto ret = find(req_url, &nodes_[node->param_childrens[(int)ParamType::DOUBLE]], eptr - req_url.data(), params);
+                        update_found(ret);
+                        params->double_params.pop_back();
+                    }
+                }
+            }
+
+            if (node->param_childrens[(int)ParamType::STRING])
+            {
+                size_t epos = pos;
+                for(; epos < req_url.size(); epos ++)
+                {
+                    if (req_url[epos] == '/')
+                        break;
+                }
+
+                if (epos != pos)
+                {
+                    params->string_params.push_back(req_url.substr(pos, epos-pos));
+                    auto ret = find(req_url, &nodes_[node->param_childrens[(int)ParamType::STRING]], epos, params);
+                    update_found(ret);
+                    params->string_params.pop_back();
+                }
+            }
+
+            if (node->param_childrens[(int)ParamType::PATH])
+            {
+                size_t epos = req_url.size();
+
+                if (epos != pos)
+                {
+                    params->string_params.push_back(req_url.substr(pos, epos-pos));
+                    auto ret = find(req_url, &nodes_[node->param_childrens[(int)ParamType::PATH]], epos, params);
+                    update_found(ret);
+                    params->string_params.pop_back();
+                }
+            }
+
+            for(auto& kv : node->children)
+            {
+                const std::string& fragment = kv.first;
+                const Node* child = &nodes_[kv.second];
+
+                if (req_url.compare(pos, fragment.size(), fragment) == 0)
+                {
+                    auto ret = find(req_url, child, pos + fragment.size(), params);
+                    update_found(ret);
+                }
+            }
+
+            return {found, match_params};
+        }
+
+        void add(const std::string& url, unsigned rule_index)
+        {
+            unsigned idx{0};
+
+            for(unsigned i = 0; i < url.size(); i ++)
+            {
+                char c = url[i];
+                if (c == '<')
+                {
+                    static struct ParamTraits
+                    {
+                        ParamType type;
+                        std::string name;
+                    } paramTraits[] =
+                    {
+                        { ParamType::INT, "<int>" },
+                        { ParamType::UINT, "<uint>" },
+                        { ParamType::DOUBLE, "<float>" },
+                        { ParamType::DOUBLE, "<double>" },
+                        { ParamType::STRING, "<str>" },
+                        { ParamType::STRING, "<string>" },
+                        { ParamType::PATH, "<path>" },
+                    };
+
+                    for(auto& x:paramTraits)
+                    {
+                        if (url.compare(i, x.name.size(), x.name) == 0)
+                        {
+                            if (!nodes_[idx].param_childrens[(int)x.type])
+                            {
+                                auto new_node_idx = new_node();
+                                nodes_[idx].param_childrens[(int)x.type] = new_node_idx;
+                            }
+                            idx = nodes_[idx].param_childrens[(int)x.type];
+                            i += x.name.size();
+                            break;
+                        }
+                    }
+
+                    i --;
+                }
+                else
+                {
+                    std::string piece(&c, 1);
+                    if (!nodes_[idx].children.count(piece))
+                    {
+                        auto new_node_idx = new_node();
+                        nodes_[idx].children.emplace(piece, new_node_idx);
+                    }
+                    idx = nodes_[idx].children[piece];
+                }
+            }
+            if (nodes_[idx].rule_index)
+                throw std::runtime_error("handler already exists for " + url);
+            nodes_[idx].rule_index = rule_index;
+        }
+    private:
+        void debug_node_print(Node* n, int level)
+        {
+            for(int i = 0; i < (int)ParamType::MAX; i ++)
+            {
+                if (n->param_childrens[i])
+                {
+                    CROW_LOG_DEBUG << std::string(2*level, ' ') /*<< "("<<n->param_childrens[i]<<") "*/;
+                    switch((ParamType)i)
+                    {
+                        case ParamType::INT:
+                            CROW_LOG_DEBUG << "<int>";
+                            break;
+                        case ParamType::UINT:
+                            CROW_LOG_DEBUG << "<uint>";
+                            break;
+                        case ParamType::DOUBLE:
+                            CROW_LOG_DEBUG << "<float>";
+                            break;
+                        case ParamType::STRING:
+                            CROW_LOG_DEBUG << "<str>";
+                            break;
+                        case ParamType::PATH:
+                            CROW_LOG_DEBUG << "<path>";
+                            break;
+                        default:
+                            CROW_LOG_DEBUG << "<ERROR>";
+                            break;
+                    }
+
+                    debug_node_print(&nodes_[n->param_childrens[i]], level+1);
+                }
+            }
+            for(auto& kv : n->children)
+            {
+                CROW_LOG_DEBUG << std::string(2*level, ' ') /*<< "(" << kv.second << ") "*/ << kv.first;
+                debug_node_print(&nodes_[kv.second], level+1);
+            }
+        }
+
+    public:
+        void debug_print()
+        {
+            debug_node_print(head(), 0);
+        }
+
+    private:
+        const Node* head() const
+        {
+            return &nodes_.front();
+        }
+
+        Node* head()
+        {
+            return &nodes_.front();
+        }
+
+        unsigned new_node()
+        {
+            nodes_.resize(nodes_.size()+1);
+            return nodes_.size() - 1;
+        }
+
+        std::vector<Node> nodes_;
+    };
+
+    class Router
+    {
+    public:
+        Router() : rules_(2) 
+        {
+        }
+
+        DynamicRule& new_rule_dynamic(const std::string& rule)
+        {
+            auto ruleObject = new DynamicRule(rule);
+
+            internal_add_rule_object(rule, ruleObject);
+
+            return *ruleObject;
+        }
+
+        template <uint64_t N>
+        typename black_magic::arguments<N>::type::template rebind<TaggedRule>& new_rule_tagged(const std::string& rule)
+        {
+            using RuleT = typename black_magic::arguments<N>::type::template rebind<TaggedRule>;
+            auto ruleObject = new RuleT(rule);
+
+            internal_add_rule_object(rule, ruleObject);
+
+            return *ruleObject;
+        }
+
+        void internal_add_rule_object(const std::string& rule, BaseRule* ruleObject)
+        {
+            rules_.emplace_back(ruleObject);
+            trie_.add(rule, rules_.size() - 1);
+
+            // directory case: 
+            //   request to `/about' url matches `/about/' rule 
+            if (rule.size() > 1 && rule.back() == '/')
+            {
+                std::string rule_without_trailing_slash = rule;
+                rule_without_trailing_slash.pop_back();
+                trie_.add(rule_without_trailing_slash, RULE_SPECIAL_REDIRECT_SLASH);
+            }
+        }
+
+        void validate()
+        {
+            trie_.validate();
+            for(auto& rule:rules_)
+            {
+                if (rule)
+                    rule->validate();
+            }
+        }
+
+        void handle(const request& req, response& res)
+        {
+            auto found = trie_.find(req.url);
+
+            unsigned rule_index = found.first;
+            CROW_LOG_DEBUG << "???" << rule_index;
+
+            if (!rule_index)
+            {
+                CROW_LOG_DEBUG << "Cannot match rules " << req.url;
+                res = response(404);
+                res.end();
+                return;
+            }
+
+            if (rule_index >= rules_.size())
+                throw std::runtime_error("Trie internal structure corrupted!");
+
+            if (rule_index == RULE_SPECIAL_REDIRECT_SLASH)
+            {
+                CROW_LOG_INFO << "Redirecting to a url with trailing slash: " << req.url;
+                res = response(301);
+
+                // TODO absolute url building
+                if (req.get_header_value("Host").empty())
+                {
+                    res.add_header("Location", req.url + "/");
+                }
+                else
+                {
+                    res.add_header("Location", "http://" + req.get_header_value("Host") + req.url + "/");
+                }
+                res.end();
+                return;
+            }
+
+            if ((rules_[rule_index]->get_methods() & (1<<(uint32_t)req.method)) == 0)
+            {
+                CROW_LOG_DEBUG << "Rule found but method mismatch: " << req.url << " with " << method_name(req.method) << "(" << (uint32_t)req.method << ") / " << rules_[rule_index]->get_methods();
+                res = response(404);
+                res.end();
+                return;
+            }
+
+            CROW_LOG_DEBUG << "Matched rule '" << rules_[rule_index]->rule_ << "' " << (uint32_t)req.method << " / " << rules_[rule_index]->get_methods();
+
+            // any uncaught exceptions become 500s
+            try
+            {
+                rules_[rule_index]->handle(req, res, found.second);
+            }
+            catch(std::exception& e)
+            {
+                CROW_LOG_ERROR << "An uncaught exception occurred: " << e.what();
+                res = response(500);
+                res.end();
+                return;   
+            }
+            catch(...)
+            {
+                CROW_LOG_ERROR << "An uncaught exception occurred. The type was unknown so no information was available.";
+                res = response(500);
+                res.end();
+                return;   
+            }
+        }
+
+        void debug_print()
+        {
+            trie_.debug_print();
+        }
+
+    private:
+        std::vector<std::unique_ptr<BaseRule>> rules_;
+        Trie trie_;
+    };
+}