Udho (উধো)

udho is a tiny http library based on Boost.Beast.

Boost.Beast is based on Boost.Asio which provides low level asynchronous I/O. udho was originally created to add HTTP functionality to an existing application that is using Boost.Asio.

std::string world(udho::contexts::stateless ctx){
return"{'planet': 'Earth'}";
}
std::string planet(udho::contexts::stateless ctx, std::string name){
return"Hello "+name;
}
intmain(){
boost::asio::io_service io;
udho::servers::ostreamed::stateless server(io, std::cout);
server[udho::configs::server::document_root] = "/path/to/static/files";
auto urls = udho::router() | "/world" >> udho::get(&world).json() | "/planet/(\\w+)" >> udho::get(&planet).plain();
server.serve(urls, 9198);
io.run();
return0;
}

Dependencies:

boost depend on boost-beast library. As boost-beast is only available on boost >= 1.66, udho requires a boost version at least 1.66. udho may optionally use ICU library for unicode regex functionality. In that case ICU library may be required.

• boost > 1.66
• pugixml
• icu [optional]

Features:

• regular expression based url routing to callables (functions / function objects)
• compile time binding of routing rule with callables
• compile time travarsable url router
• response mime type specification in routing rule
• any default constructible can be used as callable argument type that can be parsed from std::string
• any ostreamable can be used as return type of callables
• automatic type coersion for url based method calling
• throwable http error messages
• serving static content from disk document root if no rule matched
• urlencoded/multipart form parsing
• on memory session for stateful web applications (no globals) and no session for stateless applications
• strictly typed on memory session storage
• compile time pluggable logging
• customizable logging
• typesafe configuration

Example

std::string login(udho::contexts::stateful<user> ctx){ /// < strictly typed stateful contextconststatic username = "derp";
conststatic password = "derp123";
if(ctx.session().exists<user>()){
user data;
ctx.session() >> data; /// < extract session datareturn"already logged in";
}else{
if(ctx.form().has("user") && ctx.form().has("pass")){
std::string usr = ctx.form().field<std::string>("user"); /// < form field value from post request
std::string psw = ctx.form().field<std::string>("pass"); /// < form field value from post requestif(usr == username && psw == password){
ctx.session() << user(usr); /// < put data in sessionreturn"successful";
}
}
}
return"failed";
}
std::string echo(udho::contexts::stateful<user> ctx, int num){
if(ctx.session().exists<user>()){
user data;
ctx.session() >> data;
returnboost::format("{'name': '%1%', 'num': %2%}") % data.name % num;
}
return"{}";
}
intmain(){
boost::asio::io_service io;
udho::servers::ostreamed::stateful<user> server(io, std::cout);
server[udho::configs::server::document_root] = "/path/to/static/files";
auto router = udho::router()
| (udho::post(&login).plain() = "^/login$")
| (udho::get(&echo).json() = "^/echo/(\\d+)$");
server.serve(router, 9198);
io.run();
return0;
}