Crow/routing.h
2014-04-16 02:57:18 +09:00

616 lines
20 KiB
C++

#pragma once
#include <cstdint>
#include <utility>
#include <tuple>
#include <unordered_map>
#include <memory>
#include <boost/lexical_cast.hpp>
#include "common.h"
#include "http_response.h"
#include "http_request.h"
#include "utility.h"
//TEST
#include <iostream>
namespace flask
{
class BaseRule
{
public:
BaseRule(std::string rule)
: rule_(std::move(rule))
{
}
virtual ~BaseRule()
{
}
BaseRule& name(std::string name)
{
name_ = std::move(name);
return *this;
}
virtual void validate() = 0;
virtual response handle(const request&, const routing_params&) = 0;
protected:
std::string rule_;
std::string name_;
};
class Rule : public BaseRule
{
public:
Rule(std::string rule)
: BaseRule(std::move(rule))
{
}
Rule& name(std::string name)
{
name_ = std::move(name);
return *this;
}
template <typename Func>
void operator()(Func&& f)
{
static_assert(black_magic::CallHelper<Func, black_magic::S<>>::value,
"Handler type is mismatched with URL paramters");
static_assert(!std::is_same<void, decltype(f())>::value,
"Handler function cannot have void return type; valid return types: string, int, flask::resposne");
handler_ = [f = std::move(f)]{
return response(f());
};
}
template <typename Func>
void operator()(std::string name, Func&& f)
{
static_assert(black_magic::CallHelper<Func, black_magic::S<>>::value,
"Handler type is mismatched with URL paramters");
name_ = std::move(name);
handler_ = [f = std::move(f)]{
return response(f());
};
}
void validate()
{
if (!handler_)
{
throw std::runtime_error(name_ + (!name_.empty() ? ": " : "") + "no handler for url " + rule_);
}
}
response handle(const request&, const routing_params&)
{
return handler_();
}
protected:
std::function<response()> handler_;
};
template <typename ... Args>
class TaggedRule : public BaseRule
{
private:
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...>>
{
response operator()(F& handler, const routing_params& params)
{
using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<int64_t, NInt>>;
return call<F, NInt+1, NUint, NDouble, NString,
black_magic::S<Args1...>, pushed>()(handler, params);
}
};
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...>>
{
response operator()(F& handler, const routing_params& params)
{
using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<uint64_t, NUint>>;
return call<F, NInt, NUint+1, NDouble, NString,
black_magic::S<Args1...>, pushed>()(handler, params);
}
};
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...>>
{
response operator()(F& handler, const routing_params& params)
{
using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<double, NDouble>>;
return call<F, NInt, NUint, NDouble+1, NString,
black_magic::S<Args1...>, pushed>()(handler, params);
}
};
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...>>
{
response operator()(F& handler, const routing_params& params)
{
using pushed = typename black_magic::S<Args2...>::template push_back<call_pair<std::string, NString>>;
return call<F, NInt, NUint, NDouble, NString+1,
black_magic::S<Args1...>, pushed>()(handler, params);
}
};
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...>>
{
response operator()(F& handler, const routing_params& params)
{
return handler(
params.get<typename Args1::type>(Args1::pos)...
);
}
};
public:
TaggedRule(std::string rule)
: BaseRule(std::move(rule))
{
}
TaggedRule<Args...>& name(std::string name)
{
name_ = std::move(name);
return *this;
}
void validate()
{
}
template <typename Func>
void operator()(Func&& f)
{
static_assert(black_magic::CallHelper<Func, black_magic::S<Args...>>::value,
"Handler type is mismatched with URL paramters");
static_assert(!std::is_same<void, decltype(f(std::declval<Args>()...))>::value,
"Handler function cannot have void return type; valid return types: string, int, flask::resposne");
handler_ = [f = std::move(f)](Args ... args){
return response(f(args...));
};
}
template <typename Func>
void operator()(std::string name, Func&& f)
{
static_assert(black_magic::CallHelper<Func, black_magic::S<Args...>>::value,
"Handler type is mismatched with URL paramters");
static_assert(!std::is_same<void, decltype(f(std::declval<Args>()...))>::value,
"Handler function cannot have void return type; valid return types: string, int, flask::resposne");
name_ = std::move(name);
handler_ = [f = std::move(f)](Args ... args){
return response(f(args...));
};
}
response handle(const request&, const routing_params& params)
{
//return handler_();
return call<decltype(handler_), 0, 0, 0, 0, black_magic::S<Args...>, black_magic::S<>>()(handler_, params);
//return response(500);
}
private:
std::function<response(Args...)> handler_;
template <typename T, int Pos>
struct call_pair
{
using type = T;
static const int pos = Pos;
};
};
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 request& req, 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 = 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, &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, &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, &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, &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, &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, 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 == '<')
{
bool found = false;
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 it = std::begin(paramTraits); it != std::end(paramTraits); ++it)
{
if (url.compare(i, it->name.size(), it->name) == 0)
{
if (!nodes_[idx].param_childrens[(int)it->type])
{
auto new_node_idx = new_node();
nodes_[idx].param_childrens[(int)it->type] = new_node_idx;
}
idx = nodes_[idx].param_childrens[(int)it->type];
i += it->name.size();
found = true;
break;
}
}
if (!found)
{
throw std::runtime_error("Invalid parameter type: " + url +
" (" + boost::lexical_cast<std::string>(i) + ")");
}
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])
{
std::cerr << std::string(2*level, ' ') /*<< "("<<n->param_childrens[i]<<") "*/;
switch((ParamType)i)
{
case ParamType::INT:
std::cerr << "<int>";
break;
case ParamType::UINT:
std::cerr << "<uint>";
break;
case ParamType::DOUBLE:
std::cerr << "<float>";
break;
case ParamType::STRING:
std::cerr << "<str>";
break;
case ParamType::PATH:
std::cerr << "<path>";
break;
default:
std::cerr << "<ERROR>";
break;
}
std::cerr << std::endl;
debug_node_print(&nodes_[n->param_childrens[i]], level+1);
}
}
for(auto& kv : n->children)
{
std::cerr << std::string(2*level, ' ') /*<< "(" << kv.second << ") "*/ << kv.first << std::endl;
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_(1) {}
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);
rules_.emplace_back(ruleObject);
trie_.add(rule, rules_.size() - 1);
return *ruleObject;
}
Rule& new_rule(const std::string& rule)
{
Rule* r(new Rule(rule));
rules_.emplace_back(r);
trie_.add(rule, rules_.size() - 1);
return *r;
}
void validate()
{
trie_.validate();
for(auto& rule:rules_)
{
if (rule)
rule->validate();
}
}
response handle(const request& req)
{
auto found = trie_.find(req);
unsigned rule_index = found.first;
if (!rule_index)
return response(404);
if (rule_index >= rules_.size())
throw std::runtime_error("Trie internal structure corrupted!");
return rules_[rule_index]->handle(req, found.second);
}
void debug_print()
{
trie_.debug_print();
}
private:
std::vector<std::unique_ptr<BaseRule>> rules_;
Trie trie_;
};
}