rest: add cache/list

Add GET cache/list request to obtain information about the client's
cache.

Resquest payload structure:
{
    'clients': ['10.141.10.21', '10.141.10.22']
}

Response's structure:
{
    'clients': [
        {
            'ip': '10.141.10.21',
            'cache_size': 2894572304857,
            'images': [
                {name:'img1', size: 87283902343, checksum: '5d4dcc677bc19f40a647d0002f4ade90'},
                {name:'img2', size: 894572304857, checksum: '3eb22f888f88a55ad954f55644e1192e'}
            ]
        },
        {
            'ip': '10.141.10.22',
            'cache_size': 49872839023434,
            'images': [
                {name:'img2', size: 894572304857, checksum: '3eb22f888f88a55ad954f55644e1192e'}
            ]
        }
    ]
}

Both 'cache_size' and the values in 'image_sizes' are provided
as bytes.

If a client has no cache partition the payload will include it as:
...
	{
            'ip': '10.141.10.22',
            'cache_size': 0,
            'images': []
        }
...

src/rest.c

@@ -3458,6 +3458,153 @@ static int og_cmd_delete_image(json_t *element, struct og_msg_params *params)
 	return 0;
 }
 
+static int og_dbi_client_cache_get(struct og_dbi *dbi, json_t *clients, const char *ip)
+{
+	const char *img_name, *msglog, *img_checksum;
+	json_t *client_data, *cache_arr, *img_info;
+	uint64_t img_size, cache_size = 0;
+	dbi_result result;
+
+	result = dbi_conn_queryf(dbi->conn,
+			"SELECT ordenadores_particiones.tamano "
+			"FROM ordenadores_particiones JOIN ordenadores "
+			"ON ordenadores.idordenador = ordenadores_particiones.idordenador "
+			"WHERE ordenadores.ip = '%s' AND codpar = 202", ip);
+	if (!result) {
+		dbi_conn_error(dbi->conn, &msglog);
+		syslog(LOG_ERR, "failed to query database (%s:%d) %s\n",
+		       __func__, __LINE__, msglog);
+		return -1;
+	}
+
+	if (dbi_result_next_row(result)) {
+		cache_size = dbi_result_get_longlong(result, "tamano") * 1024;
+	}
+
+	dbi_result_free(result);
+
+	result = dbi_conn_queryf(dbi->conn,
+			"SELECT cache.imagename, cache.size, cache.checksum "
+			"FROM ordenadores JOIN cache "
+			"ON ordenadores.idordenador = cache.clientid "
+			"WHERE ordenadores.ip = '%s'", ip);
+
+	if (!result) {
+		dbi_conn_error(dbi->conn, &msglog);
+		syslog(LOG_ERR, "failed to query database (%s:%d) %s\n",
+		       __func__, __LINE__, msglog);
+		return -1;
+	}
+
+	client_data = json_object();
+	if (!client_data) {
+		dbi_result_free(result);
+		return -1;
+	}
+
+	cache_arr = json_array();
+	if (!cache_arr) {
+		json_decref(client_data);
+		dbi_result_free(result);
+		return -1;
+	}
+
+	while (dbi_result_next_row(result)) {
+		img_name = dbi_result_get_string(result, "imagename");
+		img_size = dbi_result_get_ulonglong(result, "size");
+		img_checksum = dbi_result_get_string(result, "checksum");
+
+		img_info = json_object();
+		if (!img_info) {
+			json_decref(client_data);
+			json_decref(cache_arr);
+			dbi_result_free(result);
+			return -1;
+		}
+
+		json_object_set_new(img_info, "name", json_string(img_name));
+		json_object_set_new(img_info, "size", json_integer(img_size));
+		json_object_set_new(img_info, "checksum", json_string(img_checksum));
+		json_array_append_new(cache_arr, img_info);
+	}
+
+	json_object_set_new(client_data, "ip", json_string(ip));
+	json_object_set_new(client_data, "cache_size", json_integer(cache_size));
+	json_object_set_new(client_data, "images", cache_arr);
+	json_array_append_new(clients, client_data);
+	dbi_result_free(result);
+
+	return 0;
+}
+
+static int og_cmd_cache_list(json_t *element, struct og_msg_params *params,
+			    char *buffer_reply)
+{
+	json_t *value, *root, *clients;
+	struct og_dbi *dbi;
+	const char *key;
+	int err = 0, i;
+
+	struct og_buffer og_buffer = {
+		.data = buffer_reply
+	};
+
+	if (json_typeof(element) != JSON_OBJECT)
+		return -1;
+
+	json_object_foreach(element, key, value) {
+		if (!strcmp(key, "clients"))
+			err = og_json_parse_clients(value, params);
+		else
+			err = -1;
+
+		if (err < 0)
+			return err;
+	}
+
+	if (!og_msg_params_validate(params, OG_REST_PARAM_ADDR))
+		return -1;
+
+	clients = json_array();
+	if (!clients)
+		return -1;
+
+	dbi = og_dbi_open(&ogconfig.db);
+	if (!dbi) {
+		syslog(LOG_ERR, "cannot open connection database (%s:%d)\n",
+		       __func__, __LINE__);
+		json_decref(clients);
+		return -1;
+	}
+
+	for (i = 0; i < params->ips_array_len; i++) {
+		if (og_dbi_client_cache_get(dbi, clients, params->ips_array[i]) < 0) {
+			json_decref(clients);
+			og_dbi_close(dbi);
+			return -1;
+		}
+	}
+
+	og_dbi_close(dbi);
+
+	root = json_object();
+	if (!root) {
+		json_decref(clients);
+		return -1;
+	}
+
+	json_object_set_new(root, "clients", clients);
+
+	if (json_dump_callback(root, og_json_dump_clients, &og_buffer, 0)) {
+		json_decref(root);
+		return -1;
+	}
+
+	json_decref(root);
+
+	return 0;
+}
+
 static int og_cmd_setup(json_t *element, struct og_msg_params *params)
 {
 	json_t *value, *clients;
@@ -7312,6 +7459,7 @@ struct {
 	[OG_URI_IMAGE_UPDATE]	= { "image/update" },
 	[OG_URI_IMAGE_RESTORE]	= { "image/restore", },
 	[OG_URI_IMAGE_DELETE]	= { "image/delete", },
+	[OG_URI_CACHE_LIST]	= { "cache/list", },
 	[OG_URI_PART_SETUP]	= { "setup", },
 	[OG_URI_RUN_SCHEDULE]	= { "run/schedule", },
 	[OG_URI_TASK_RUN]	= { "task/run", },
@@ -7884,6 +8032,19 @@ int og_client_state_process_payload_rest(struct og_client *cli)
 			goto err_process_rest_payload;
 		}
 		err = og_cmd_delete_image(root, &params);
+	} else if (!strncmp(cmd, "cache/list", strlen("cache/list"))) {
+		if (method != OG_METHOD_GET) {
+			err = og_client_method_not_found(cli);
+			goto err_process_rest_payload;
+		}
+
+		if (!root) {
+			syslog(LOG_ERR,
+			       "command cache list with no payload\n");
+			err = og_client_bad_request(cli);
+			goto err_process_rest_payload;
+		}
+		err = og_cmd_cache_list(root, &params, buf_reply);
 	} else if (!strncmp(cmd, "setup", strlen("setup"))) {
 		if (method != OG_METHOD_POST) {
 			err = og_client_method_not_found(cli);

src/rest.h

@@ -116,6 +116,7 @@ enum og_rest_uri {
 	OG_URI_IMAGE_UPDATE,
 	OG_URI_IMAGE_RESTORE,
 	OG_URI_IMAGE_DELETE,
+	OG_URI_CACHE_LIST,
 	OG_URI_PART_SETUP,
 	OG_URI_RUN_SCHEDULE,
 	OG_URI_TASK_RUN,