rest: add /server GET and POST methods

DB stores different ogserver addresses in the "entornos" table.

Expose addition and deletion operations for the "entornos" table using
the /server endpoint.

GET /server returns a list of rows from the "entornos" table including
the "identorno" and "ipserveradm" columns. For example:

>>>
GET /server

<<<
200 OK
...
{
  "servers": [
    {
      "id": 1,
      "address": "10.141.10.1"
    }
  ]
}

POST /server inserts into the "entornos" table and returns the
id ("identorno") of the new row.

>>>
POST /server
{
  "address": "192.168.2.240"
}

<<<
200 OK
...
{
  "id": 2
}

If the server address already exists the response is 400 Bad Request
with no payload.

>>>
POST /server
{
  "address": "192.168.2.240"
}

<<<
400 Bad Request

src/rest.c

@@ -5537,6 +5537,158 @@ err_return:
 	return -1;
 }
 
+static int og_cmd_get_servers(char *buffer_reply)
+{
+	json_t *root, *servers, *address;
+	struct og_buffer og_buffer = {
+		.data	= buffer_reply,
+	};
+	char ipaddr[50] = {};
+	struct og_dbi *dbi;
+	dbi_result result;
+	int id, ret;
+
+	root = json_object();
+	if (!root)
+		return -1;
+
+	servers = json_array();
+	if (!servers) {
+		json_decref(root);
+		return -1;
+	}
+
+
+	dbi = og_dbi_open(&ogconfig.db);
+	if (!dbi) {
+		syslog(LOG_ERR, "cannot open connection database (%s:%d)\n",
+		       __func__, __LINE__);
+		json_decref(root);
+		return -1;
+	}
+
+	result = dbi_conn_queryf(dbi->conn,
+				 "SELECT identorno, ipserveradm "
+				 "FROM entornos");
+
+	while (dbi_result_next_row(result)) {
+		address = json_object();
+		id = dbi_result_get_int(result, "identorno");
+		snprintf(ipaddr, sizeof(ipaddr), "%s",
+			 dbi_result_get_string(result, "ipserveradm"));
+
+		json_object_set_new(address, "id", json_integer(id));
+		json_object_set_new(address, "address", json_string(ipaddr));
+
+		json_array_append_new(servers, address);
+	}
+
+	json_object_set_new(root, "servers", servers);
+
+	dbi_result_free(result);
+	og_dbi_close(dbi);
+
+	ret = json_dump_callback(root, og_json_dump_clients, &og_buffer, 0);
+	json_decref(root);
+
+	return ret;
+}
+
+static int og_cmd_post_server(json_t *element,
+				   struct og_msg_params *params,
+				   char *buffer_reply)
+{
+	struct og_buffer og_buffer = {
+		.data	= buffer_reply,
+	};
+	const char *key, *msglog;
+	json_t *value, *root;
+	int err = 0, id, ret;
+	struct in_addr addr;
+	struct og_dbi *dbi;
+	dbi_result result;
+
+	json_object_foreach(element, key, value) {
+		if (!strcmp(key, "address")) {
+			err = og_json_parse_string(value, &params->name);
+			params->flags |= OG_REST_PARAM_NAME;
+		}
+
+		if (err < 0)
+			return err;
+	}
+
+	if (!og_msg_params_validate(params, OG_REST_PARAM_NAME))
+		return -1;
+
+	if (inet_pton(AF_INET, params->name, &addr) <= 0) {
+		syslog(LOG_ERR, "invalid server ip address (%s:%d)\n",
+		       __func__, __LINE__);
+		return -1;
+	}
+
+	dbi = og_dbi_open(&ogconfig.db);
+	if (!dbi) {
+		syslog(LOG_ERR, "cannot open conection database (%s:%d)\n",
+		       __func__, __LINE__);
+		return -1;
+	}
+
+	result = dbi_conn_queryf(dbi->conn,
+				 "SELECT identorno FROM entornos WHERE ipserveradm='%s'",
+				 params->name);
+
+	if (!result) {
+		dbi_conn_error(dbi->conn, &msglog);
+		syslog(LOG_ERR, "failed to query database (%s:%d) %s\n",
+		       __func__, __LINE__, msglog);
+		og_dbi_close(dbi);
+		return -1;
+	}
+
+	if (dbi_result_get_numrows(result) > 0) {
+		syslog(LOG_ERR, "Address %s already exists\n",
+		       params->name);
+		dbi_result_free(result);
+		og_dbi_close(dbi);
+		return -1;
+	}
+	dbi_result_free(result);
+
+	result = dbi_conn_queryf(dbi->conn,
+				 "INSERT INTO entornos("
+				 "  ipserveradm,"
+				 "  protoclonacion) VALUES ("
+				 "'%s', 'UNICAST')",
+				 params->name);
+
+	if (!result) {
+		dbi_conn_error(dbi->conn, &msglog);
+		syslog(LOG_ERR, "failed to add new ogserver address to database (%s:%d) %s\n",
+		       __func__, __LINE__, msglog);
+		og_dbi_close(dbi);
+		return -1;
+	}
+
+	root = json_object();
+	if (!root) {
+		syslog(LOG_ERR, "Cannot allocate JSON object (%s:%d)\n",
+		       __func__, __LINE__);
+		dbi_result_free(result);
+		og_dbi_close(dbi);
+		return -1;
+	}
+	id = dbi_conn_sequence_last(dbi->conn, NULL);
+	json_object_set_new(root, "id", json_integer(id));
+	ret = json_dump_callback(root, og_json_dump_clients, &og_buffer, 0);
+
+	json_decref(root);
+	dbi_result_free(result);
+	og_dbi_close(dbi);
+
+	return ret;
+}
+
 static int og_dbi_update_oglive(struct og_dbi *dbi, const char *mac,
 				const char * oglive)
 {
@@ -6366,6 +6518,23 @@ int og_client_state_process_payload_rest(struct og_client *cli)
 			goto err_process_rest_payload;
 		}
 		err = og_cmd_post_task_add(root, &params);
+	} else if (!strncmp(cmd, "server", strlen("server"))) {
+		switch (method) {
+		case OG_METHOD_GET:
+			err = og_cmd_get_servers(buf_reply);
+			break;
+		case OG_METHOD_POST:
+			if (!root) {
+				syslog(LOG_ERR, "address add command with no payload\n");
+				err = og_client_bad_request(cli);
+				goto err_process_rest_payload;
+			}
+			err = og_cmd_post_server(root, &params, buf_reply);
+			break;
+		default:
+			err = og_client_method_not_found(cli);
+			goto err_process_rest_payload;
+		}
 	} else if (!strncmp(cmd, "stats", strlen("stats"))) {
 		if (method != OG_METHOD_GET) {
 			err = og_client_method_not_found(cli);