mongoose web server helloworld program

Question

I came across an embedded web server named mongoose and http://code.google.com/p/mongoose/ and I read the wiki it was great and i searched for some sample hello world program but i couldn't find it... i found some example but that was written in c++ for windows and can any one provide an example c program to run this webserver..

Answer 1

It is quite simple, first you need to implement the call back function:

void *event_handler(enum mg_event event,
    struct mg_connection *conn) {

    const struct mg_request_info *request_info = mg_get_request_info(conn);

    static void* done = "done";

    if (event == MG_NEW_REQUEST) {
        if (strcmp(request_info->uri, "/hello") == 0) {
            // handle c[renderer] request
            if(strcmp(request_info->request_method, "GET") != 0) {
                // send error (we only care about HTTP GET)
                mg_printf(conn, "HTTP/1.1 %d Error (%s)\r\n\r\n%s",
                    500,
                    "we only care about HTTP GET",
                    "we only care about HTTP GET");
                // return not null means we handled the request
                return done;
            }

            // handle your GET request to /hello
            char* content = "Hello World!";
            char* mimeType = "text/plain";
            int contentLength = strlen(content);

            mg_printf(conn,
                "HTTP/1.1 200 OK\r\n"
                "Cache: no-cache\r\n"
                "Content-Type: %s\r\n"
                "Content-Length: %d\r\n"
                "\r\n",
                mimeType,
                contentLength);
            mg_write(conn, content, contentLength);
            return done;
            }
        }
        // in this example i only handle /hello
        mg_printf(conn, "HTTP/1.1 %d Error (%s)\r\n\r\n%s",
            500, /* This the error code you want to send back*/
            "Invalid Request.",
            "Invalid Request.");
        return done;
    }

    // No suitable handler found, mark as not processed. Mongoose will
    // try to serve the request.
    return NULL;
}

Then you need to start the server:

int main(int argc, char **argv) {

    /* Default options for the HTTP server */
    const char *options[] = {
        "listening_ports", "8081",
        "num_threads", "10",
        NULL
    };

    /* Initialize HTTP layer */
    static struct mg_context *ctx;

    ctx = mg_start(&event_handler, options);
    if(ctx == NULL) {
        exit(EXIT_FAILURE);
    }

    puts("Server running, press enter to exit\n");
    getchar();
    mg_stop(ctx);

    return EXIT_SUCCESS;
}

Answer 2

For anyone looking at this thread - from the mongoose library author (me).

Mongoose web server has long ago moved to https://github.com/cesanta/mongoose

It has a comprehensive list of examples, starting from a simplest ones, to the more complex ones, see examples directory in the repository. The minimal static HTTP server goes as follows:

#include "mongoose.h"

static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
  struct mg_http_serve_opts opts = {.root_dir = "."};   // Serve local dir
  if (ev == MG_EV_HTTP_MSG) mg_http_serve_dir(c, ev_data, &opts);
}

int main(int argc, char *argv[]) {
  struct mg_mgr mgr;
  mg_mgr_init(&mgr);                                        // Init manager
  mg_http_listen(&mgr, "http://localhost:8000", fn, &mgr);  // Setup listener
  for (;;) mg_mgr_poll(&mgr, 1000);                         // Event loop
  mg_mgr_free(&mgr);                                        // Cleanup
  return 0;
}

Answer 3

I wrote a C++ REST service library that uses Mongoose. Here's a simple example:

#include <iostream>
#include <server/server.hpp>

int main()
{
  using namespace pwned::server;
  Server server;

  server.Get("/", [](mg_event*, Params const &) {
    return Server::response("Hello!");
  });

  std::cin.get();
}

Based on https://github.com/nurettin/pwned/blob/master/examples/server/basics/server.cpp

Answer 4

Compile application: $ cc my_app.c mongoose.c

#include "mongoose.h"  // Include Mongoose API definitions


static const char *s_http_port = "8089";


// Define an event handler function
static void ev_handler(struct mg_connection *nc, int ev, void *ev_data) 
{
    struct mbuf *io = &nc->recv_mbuf;

    switch (ev) 
    {
    case MG_EV_RECV:

        // This event handler implements simple TCP echo server
        mg_send(nc, io->buf, io->len);  // Echo received data back

        mbuf_remove(io, io->len);      // Discard data from recv buffer

        break;

    default:
        break;
    }
}



int main(void)
{
    struct mg_mgr mgr;

    mg_mgr_init(&mgr, NULL);  // Initialize event manager object

    // Note that many connections can be added to a single event manager
    // Connections can be created at any point, e.g. in event handler    function
    mg_bind(&mgr, s_http_port, ev_handler);  // Create listening connection   and add it to the event manager

    for (;;) 
    {  
        // Start infinite event loop
        mg_mgr_poll(&mgr, 1000);
    }

    mg_mgr_free(&mgr);
    return 0;
}