src/rsensor.c

   1 /*
   2  * Copyright (C) 2010-2011 jeanfi@gmail.com
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301 USA
  18  */
  19 #include <locale.h>
  20 #include <libintl.h>
  21 #define _(str) gettext(str)
  22
  23 #include "url.h"
  24 #include "server/server.h"
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include <curl/curl.h>
  31 #include <json/json.h>
  32
  33 #include "rsensor.h"
  34
  35 struct ucontent {
  36         char *data;
  37         size_t len;
  38 };
  39
  40 static CURL *curl;
  41
  42 static size_t cbk_curl(void *buffer, size_t size, size_t nmemb, void *userp)
  43 {
  44         size_t realsize;
  45         struct ucontent *mem;
  46
  47         realsize = size * nmemb;
  48         mem = (struct ucontent *)userp;
  49
  50         mem->data = realloc(mem->data, mem->len + realsize + 1);
  51
  52         memcpy(&(mem->data[mem->len]), buffer, realsize);
  53         mem->len += realsize;
  54         mem->data[mem->len] = 0;
  55
  56         return realsize;
  57 }
  58
  59 static char *create_api_1_0_sensors_url(const char *base_url)
  60 {
  61         char *nurl, *ret;
  62         int n;
  63
  64         nurl = url_normalize(base_url);
  65         n = strlen(nurl) + strlen(URL_BASE_API_1_0_SENSORS) + 1;
  66         ret = malloc(n);
  67
  68         strcpy(ret, nurl);
  69         strcat(ret, URL_BASE_API_1_0_SENSORS);
  70
  71         free(nurl);
  72
  73         return ret;
  74 }
  75
  76 static struct psensor *json_object_to_psensor(json_object * o,
  77                                               const char *sensors_url,
  78                                               int values_max_length)
  79 {
  80         json_object *oid;
  81         json_object *oname;
  82         json_object *otype;
  83         struct psensor *s;
  84         char *eid;
  85         char *url;
  86
  87         oid = json_object_object_get(o, "id");
  88         oname = json_object_object_get(o, "name");
  89         otype = json_object_object_get(o, "type");
  90
  91         eid = url_encode(json_object_get_string(oid));
  92         url = malloc(strlen(sensors_url) + 1 + strlen(eid) + 1);
  93         sprintf(url, "%s/%s", sensors_url, eid);
  94
  95         s = psensor_create(strdup(url),
  96                            strdup(json_object_get_string(oname)),
  97                            json_object_get_int(otype) | SENSOR_TYPE_REMOTE,
  98                            values_max_length);
  99         s->url = url;
 100
 101         free(eid);
 102
 103         return s;
 104 }
 105
 106 void rsensor_init()
 107 {
 108         curl = curl_easy_init();
 109 }
 110
 111 void rsensor_cleanup()
 112 {
 113         curl_easy_cleanup(curl);
 114 }
 115
 116 static json_object *get_json_object(const char *url)
 117 {
 118         struct ucontent chunk;
 119         json_object *obj;
 120
 121         obj = NULL;
 122
 123         if (!curl)
 124                 return NULL;
 125
 126         chunk.data = malloc(1);
 127         chunk.len = 0;
 128
 129         curl_easy_setopt(curl, CURLOPT_URL, url);
 130         curl_easy_setopt(curl, CURLOPT_VERBOSE, 0);
 131         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, cbk_curl);
 132         curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&chunk);
 133
 134         log_printf(LOG_DEBUG, "HTTP request %s", url);
 135         if (curl_easy_perform(curl) == CURLE_OK)
 136                 obj = json_tokener_parse(chunk.data);
 137         else
 138                 log_printf(LOG_ERR, _("Fail to connect to: %s"), url);
 139
 140         free(chunk.data);
 141
 142         return obj;
 143 }
 144
 145 struct psensor **get_remote_sensors(const char *server_url,
 146                                     int values_max_length)
 147 {
 148         struct psensor **sensors, *s;
 149         char *url;
 150         json_object *obj;
 151         int i, n;
 152
 153         sensors = NULL;
 154
 155         url = create_api_1_0_sensors_url(server_url);
 156
 157         obj = get_json_object(url);
 158
 159         if (obj && !is_error(obj)) {
 160                 n = json_object_array_length(obj);
 161                 sensors = malloc((n + 1) * sizeof(struct psensor *));
 162
 163                 for (i = 0; i < n; i++) {
 164                         s = json_object_to_psensor
 165                                 (json_object_array_get_idx(obj, i),
 166                                  url,
 167                                  values_max_length);
 168                         sensors[i] = s;
 169                 }
 170
 171                 sensors[n] = NULL;
 172
 173                 json_object_put(obj);
 174         } else {
 175                 log_printf(LOG_ERR, _("Invalid content: %s"), url);
 176         }
 177
 178         free(url);
 179
 180         if (!sensors) {
 181                 sensors = malloc(sizeof(struct psensor *));
 182                 *sensors = NULL;
 183         }
 184
 185         return sensors;
 186 }
 187
 188 void remote_psensor_update(struct psensor *s)
 189 {
 190         json_object *obj;
 191
 192         obj = get_json_object(s->url);
 193
 194         if (obj && !is_error(obj)) {
 195                 json_object *om;
 196
 197                 om = json_object_object_get(obj, "last_measure");
 198
 199                 if (!is_error(obj)) {
 200                         json_object *ov, *ot;
 201                         struct timeval tv;
 202
 203                         ov = json_object_object_get(om, "value");
 204                         ot = json_object_object_get(om, "time");
 205
 206                         tv.tv_sec = json_object_get_int(ot);
 207                         tv.tv_usec = 0;
 208
 209                         psensor_set_current_measure
 210                             (s, json_object_get_double(ov), tv);;
 211                 }
 212
 213                 json_object_put(obj);
 214         } else {
 215                 log_printf(LOG_ERR, _("Invalid JSON: %s"), s->url);
 216         }
 217
 218 }
 219
 220 void remote_psensor_list_update(struct psensor **sensors)
 221 {
 222         struct psensor **cur;
 223
 224         cur = sensors;
 225         while (*cur) {
 226                 struct psensor *s = *cur;
 227
 228                 if (s->type & SENSOR_TYPE_REMOTE)
 229                         remote_psensor_update(s);
 230
 231                 cur++;
 232         }
 233 }