mongoose/examples/webui-plain/main.c
2023-04-14 10:13:22 -03:00

68 lines
2.4 KiB
C

// Copyright (c) 2022 Cesanta Software Limited
// All rights reserved
//
// UI example
// It implements the following endpoints:
// /api/config/get - respond with current config
// /api/config/set - POST a config change
// any other URI serves static files from s_root_dir
// Data and results are JSON strings
#include "mongoose.h"
static const char *s_http_addr = "http://localhost:8000"; // HTTP port
static const char *s_root_dir = "web_root";
#define MQTT_SERVER "mqtt://broker.hivemq.com:1883"
#define MQTT_PUBLISH_TOPIC "mg/my_device"
#define MQTT_SUBSCRIBE_TOPIC "mg/#"
static struct config {
char *url, *pub, *sub;
} s_config;
// Try to update a single configuration value
static void update_config(struct mg_str json, const char *path, char **value) {
char *jval;
if ((jval = mg_json_get_str(json, path)) != NULL) {
free(*value);
*value = strdup(jval);
}
}
static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
if (ev == MG_EV_OPEN && c->is_listening) {
s_config.url = strdup(MQTT_SERVER);
s_config.pub = strdup(MQTT_PUBLISH_TOPIC);
s_config.sub = strdup(MQTT_SUBSCRIBE_TOPIC);
} else if (ev == MG_EV_HTTP_MSG) {
struct mg_http_message *hm = (struct mg_http_message *) ev_data;
if (mg_http_match_uri(hm, "/api/config/get")) {
mg_http_reply(c, 200, "Content-Type: application/json\r\n",
"{%m:%m,%m:%m,%m:%m}\n", mg_print_esc, 0, "url",
mg_print_esc, 0, s_config.url, mg_print_esc, 0, "pub",
mg_print_esc, 0, s_config.pub, mg_print_esc, 0, "sub",
mg_print_esc, 0, s_config.sub);
} else if (mg_http_match_uri(hm, "/api/config/set")) {
struct mg_str json = hm->body;
update_config(json, "$.url", &s_config.url);
update_config(json, "$.pub", &s_config.pub);
update_config(json, "$.sub", &s_config.sub);
mg_http_reply(c, 200, "", "ok\n");
} else {
struct mg_http_serve_opts opts = {.root_dir = s_root_dir};
mg_http_serve_dir(c, ev_data, &opts);
}
}
(void) fn_data;
}
int main(void) {
struct mg_mgr mgr; // Event manager
mg_log_set(MG_LL_INFO); // Set to 3 to enable debug
mg_mgr_init(&mgr); // Initialise event manager
mg_http_listen(&mgr, s_http_addr, fn, NULL); // Create HTTP listener
for (;;) mg_mgr_poll(&mgr, 1000); // Infinite event loop
mg_mgr_free(&mgr);
return 0;
}