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, *oname, *otype;
  81         struct psensor *s;
  82         char *eid, *url;
  83
  84         oid = json_object_object_get(o, "id");
  85         oname = json_object_object_get(o, "name");
  86         otype = json_object_object_get(o, "type");
  87
  88         eid = url_encode(json_object_get_string(oid));
  89         url = malloc(strlen(sensors_url) + 1 + strlen(eid) + 1);
  90         sprintf(url, "%s/%s", sensors_url, eid);
  91
  92         s = psensor_create(strdup(url),
  93                            strdup(json_object_get_string(oname)),
  94                            json_object_get_int(otype) | SENSOR_TYPE_REMOTE,
  95                            values_max_length);
  96         s->url = url;
  97
  98         free(eid);
  99
 100         return s;
 101 }
 102
 103 void rsensor_init()
 104 {
 105         curl = curl_easy_init();
 106 }
 107
 108 void rsensor_cleanup()
 109 {
 110         curl_easy_cleanup(curl);
 111 }
 112
 113 static json_object *get_json_object(const char *url)
 114 {
 115         struct ucontent chunk;
 116         json_object *obj;
 117
 118         obj = NULL;
 119
 120         if (!curl)
 121                 return NULL;
 122
 123         chunk.data = malloc(1);
 124         chunk.len = 0;
 125
 126         curl_easy_setopt(curl, CURLOPT_URL, url);
 127         curl_easy_setopt(curl, CURLOPT_VERBOSE, 0);
 128         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, cbk_curl);
 129         curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&chunk);
 130
 131         log_printf(LOG_DEBUG, "HTTP request %s", url);
 132         if (curl_easy_perform(curl) == CURLE_OK)
 133                 obj = json_tokener_parse(chunk.data);
 134         else
 135                 log_printf(LOG_ERR, _("Fail to connect to: %s"), url);
 136
 137         free(chunk.data);
 138
 139         return obj;
 140 }
 141
 142 struct psensor **get_remote_sensors(const char *server_url,
 143                                     int values_max_length)
 144 {
 145         struct psensor **sensors, *s;
 146         char *url;
 147         json_object *obj;
 148         int i, n;
 149
 150         sensors = NULL;
 151
 152         url = create_api_1_0_sensors_url(server_url);
 153
 154         obj = get_json_object(url);
 155
 156         if (obj && !is_error(obj)) {
 157                 n = json_object_array_length(obj);
 158                 sensors = malloc((n + 1) * sizeof(struct psensor *));
 159
 160                 for (i = 0; i < n; i++) {
 161                         s = json_object_to_psensor
 162                                 (json_object_array_get_idx(obj, i),
 163                                  url,
 164                                  values_max_length);
 165                         sensors[i] = s;
 166                 }
 167
 168                 sensors[n] = NULL;
 169
 170                 json_object_put(obj);
 171         } else {
 172                 log_printf(LOG_ERR, _("Invalid content: %s"), url);
 173         }
 174
 175         free(url);
 176
 177         if (!sensors) {
 178                 sensors = malloc(sizeof(struct psensor *));
 179                 *sensors = NULL;
 180         }
 181
 182         return sensors;
 183 }
 184
 185 void remote_psensor_update(struct psensor *s)
 186 {
 187         json_object *obj;
 188
 189         obj = get_json_object(s->url);
 190
 191         if (obj && !is_error(obj)) {
 192                 json_object *om;
 193
 194                 om = json_object_object_get(obj, "last_measure");
 195
 196                 if (!is_error(obj)) {
 197                         json_object *ov, *ot;
 198                         struct timeval tv;
 199
 200                         ov = json_object_object_get(om, "value");
 201                         ot = json_object_object_get(om, "time");
 202
 203                         tv.tv_sec = json_object_get_int(ot);
 204                         tv.tv_usec = 0;
 205
 206                         psensor_set_current_measure
 207                             (s, json_object_get_double(ov), tv);;
 208                 }
 209
 210                 json_object_put(obj);
 211         } else {
 212                 log_printf(LOG_ERR, _("Invalid JSON: %s"), s->url);
 213         }
 214
 215 }
 216
 217 void remote_psensor_list_update(struct psensor **sensors)
 218 {
 219         struct psensor **cur;
 220
 221         cur = sensors;
 222         while (*cur) {
 223                 struct psensor *s = *cur;
 224
 225                 if (s->type & SENSOR_TYPE_REMOTE)
 226                         remote_psensor_update(s);
 227
 228                 cur++;
 229         }
 230 }