IncludeOS C++ Web Application Framework
Acorn is a web server built with Mana which demonstrates a lot of its potential.
Some insight in the implementation of mana can be found in this post.
It's easy to get started - check out the examples.
using namespace mana;
using namespace std::string_literals;
std::unique_ptr<Server> server;
void Service::start(const std::string&)
{
Router router;
// GET /
router.on_get("/", [](auto, auto res) {
res->add_body("<html><body><h1>Simple example</h1></body></html>"s);
res->send();
});
server = std::make_unique<Server>(net::Inet4::stack());
server->set_routes(router).listen(80);
}Routes is where the server end-points are defined.
Router router;
// GET /
router.on_get("/", [] (auto req, auto res) {
// Serve index.html
});
// POST /users
router.on_post("/users", [] (auto req, auto res) {
// Register new user
});
server.set_routes(router);There is also support for named parameters in routes.
// GET /users/:id
router.on_get("/users/:id(\\d+)", [](auto req, auto res) {
auto id = req->params().get("id");
// Do actions according to "id"
if(id == "42")
// ...
});Middleware are tasks which are executed before the user code defined in routes.
// Declare a new middleware
class MyMiddleware : public mana::Middleware {
// ...
};
// Add a middleware object
Middleware_ptr my_mw = std::make_shared<MyMiddleware>();
server.use(my_mw);It's also possible to just add a simple task with a lambda.
// Add a middleware lambda
server.use([] (auto req, auto res) {
// My custom middleware function
(*next)(); // Don't forget to call next if no response was sent!
});Psst, there is already some ready-made middleware for Mana!
Attributes is a way to extend the Request object with additional data.
// Declare a new attribute
class MyAttribute : public Attribute {
// ...
};
// Set attribute in middleware
MyMiddleware::process(auto req, auto res, auto next) {
auto attr = std::make_shared<MyAttribute>();
req->set_attribute(attr);
(*next)();
}
// Use attribute in route
router.use("/my-route", [] (auto req, auto res) {
if(auto attr = req->get_attribute<MyAttribute>()) {
// Do things with "attr"
}
});