config via shadow

mgos_conf_shadow.c

#include "mgos.h"
#include "mgos_rpc.h"
#include "mgos_shadow.h"

static void report_state_to_the_shadow(void) {
  const struct mgos_conf_entry *schema =
      mgos_conf_find_schema_entry("KEY", mgos_config_schema());
  struct mbuf mb;
  mbuf_init(&mb, 0);
  mgos_conf_emit_cb(&mgos_sys_config, NULL, schema, false, &mb, NULL, NULL);
  mgos_shadow_updatef(0, "{KEY: %.*s, uptime: %.2f}", (int) mb.len, mb.buf,
                      (float) mgos_uptime());
  mbuf_free(&mb);
}

// When we're connected to the shadow, report our current state.
// This may generate shadow delta on the cloud, and the cloud will push
// it down to us.
static void connected_cb(int ev, void *ev_data, void *userdata) {
  report_state_to_the_shadow();
  (void) ev;
  (void) ev_data;
  (void) userdata;
}

// Handle shadow delta.
static void delta_cb(int ev, void *ev_data, void *userdata) {
  struct mg_str *delta = (struct mg_str *) ev_data;
  struct json_token t = JSON_INVALID_TOKEN;
  LOG(LL_INFO, ("GOT DELTA: [%.*s]", (int) delta->len, delta->p));
  if (json_scanf(delta->p, delta->len, "{KEY: %T}", &t) == 1) {
    const struct mgos_conf_entry *schema =
        mgos_conf_find_schema_entry("KEY", mgos_config_schema());
    struct mg_str s = mg_mk_str_n(t.ptr, t.len);
    bool res = mgos_conf_parse(s, "*", schema, &mgos_sys_config);
    if (res) {
      save_cfg(&mgos_sys_config, NULL);
      LOG(LL_INFO, ("DELTA applied"));
    } else {
      LOG(LL_INFO, ("Error in config, DELTA NOT applied"));
    }
  } else {
    LOG(LL_ERROR, ("Unexpected delta, looking for {KEY: ...}"));
  }
  (void) ev;
  (void) userdata;
}

static void my_timer_cb(void *arg) {
  report_state_to_the_shadow();
  (void) arg;
}

enum mgos_app_init_result mgos_app_init(void) {
  mgos_event_add_handler(MGOS_SHADOW_UPDATE_DELTA, delta_cb, NULL);
  mgos_event_add_handler(MGOS_SHADOW_CONNECTED, connected_cb, NULL);
  mgos_set_timer(1000, MGOS_TIMER_REPEAT, my_timer_cb, NULL);
  return MGOS_APP_INIT_SUCCESS;
}