Serving static files in uWebSockets HTTP server (C++) - c++

Question

I am setting up an HTTP server in C++ using the uWebSockets library and I would like to add a middleware to serve static files, similar to what app.use(express.static(path.join(__dirname, 'public'))); does in Express.js.
The static files reside in the public folder. The middleware should make the server load files under the path http://localhost:8087/css/bootstrap.min.css, not http://localhost:8087/public/css/bootstrap.min.css, thus re-routing root to public.
How could one do this in C++ using the uWebSockets library? I already inspected the uWS::App struct, however I find there nothing related to the path or to serving static files.
Here is an example an HTTP server:
#include <uWebSockets/App.h>
#include <rapidjson/rapidjson.h>
#include "util/AsyncFileReader.h"
#include "util/AsyncFileStreamer.h"
#include <iostream>
#include <string>
void get_home(uWS::HttpResponse<false> *res, uWS::HttpRequest *req) {
res->writeHeader("Content-Type", "text/html; charset=utf8");
// res->writeStatus(uWS::HTTP_200_OK);
// res->end("Hello! This is <b>Sergei's C++ web server</b>.");
AsyncFileReader page_contents("./public/home.html");
res->end(page_contents.peek(0));
}
int main() {
int port{8087};
// HTTP
uWS::App app = uWS::App();
app.get("/", get_home);
app.listen(port, [&port](auto *token) {
if (token) {
std::cout << "Listening on port " << port << std::endl;
}
})
.run();
return 0;
}

Answer 1

There is an example with this exactly
I eventually ended up adding a directory watch and updating the html files if saved (a few changes in codebase) but i guess thats a different thing
#include "helpers/AsyncFileReader.h"
#include "helpers/AsyncFileStreamer.h"
#include "helpers/Middleware.h"
AsyncFileStreamer asyncFileStreamer("htmls"); // htmls is a relative folder path to static files
app.get("/*", gethome); // note the *
void get_home(auto *res, auto *req) {
//void get_home(uWS::HttpResponse<false> *res, uWS::HttpRequest *req) {
serveFile(res, req); // essentially res->writeStatus(uWS::HTTP_200_OK);
asyncFileStreamer.streamFile(res, req->getUrl());
}
Please note serveFile() function also needs to take care of different Content-Type header setting for images
example mentioned:
https://github.com/uNetworking/uWebSockets/blob/master/examples/HttpServer.cpp

Answer 2

To expand the answer of #amit.user105387, here is how a working solution could look like:
#include <uWebSockets/App.h>
#include <rapidjson/rapidjson.h>
#include "util/AsyncFileReader.h"
#include "util/AsyncFileStreamer.h"
#include "util/Middleware.h"
#include <iostream>
#include <string>
void get_home(uWS::HttpResponse<false> *res, uWS::HttpRequest *req) {
// res->writeHeader("Alt-Svc", "h2=\"localhost:8087\"public\"");
res->writeHeader("Content-Type", "text/html; charset=utf8");
AsyncFileReader page_contents("./public/html/home.html");
res->end(page_contents.peek(0));
}
void PrintCachedFiles(std::map<std::string_view, AsyncFileReader *> dict) {
for (auto it = dict.begin(); it != dict.end(); it++) {
std::cout << it->first << std::endl;
}
}
int main() {
const int port{8087};
const std::string public_folder{"./public"};
AsyncFileStreamer public_files("./public");
// HTTP
uWS::App app = uWS::App();
app.get("/", [&public_files](auto res, auto req){
std::cout << "root folder = "<< public_files.root << std::endl;
PrintCachedFiles(public_files.asyncFileReaders);
res->writeHeader("Content-Type", "text/html; charset=utf8");
public_files.streamFile(res, "/html/home.html");
res->writeStatus(uWS::HTTP_200_OK)->end();
});
app.get("/css/:path", [&public_files](auto res, auto req){
public_files.streamFile(res, req->getUrl());
res->writeStatus(uWS::HTTP_200_OK)->end();
});
app.get("/js/:path", [&public_files](auto res, auto req){
public_files.streamFile(res, req->getUrl());
res->writeStatus(uWS::HTTP_200_OK)->end();
});
app.get("/img/:path/*", [&public_files](auto res, auto req){
serveFile(res, req);
public_files.streamFile(res, req->getUrl());
res->writeStatus(uWS::HTTP_200_OK)->end();
});
app.get("/*", [&public_files](auto res, auto req){
res->writeStatus(uWS::HTTP_200_OK)->end("404: Page not found.");
});
app.listen(port, [&port](auto *token) {
if (token) {
std::cout << "Listening on port " << port << std::endl;
}
})
.run();
return 0;
}