int mtev_json_object_to_fd(int fd, struct mtev_json_object *obj)
{
const char *mtev_json_str;
int ret;
unsigned int wpos, wsize;
if(!obj) {
MC_ERROR("mtev_json_object_to_fd: object is null%s\n", "");
return -1;
}
if(!(mtev_json_str = mtev_json_object_to_json_string(obj))) {
return -1;
}
wsize = (unsigned int)(strlen(mtev_json_str) & UINT_MAX); /* CAW: probably unnecessary, but the most 64bit safe */
wpos = 0;
while(wpos < wsize) {
if((ret = write(fd, mtev_json_str + wpos, wsize-wpos)) < 0) {
MC_ERROR("mtev_json_object_to_fd: error writing fd %d: %s\n",
fd, strerror(errno));
return -1;
}
/* because of the above check for ret < 0, we can safely cast and add */
wpos += (unsigned int)ret;
}
return 0;
}
/**
* The "noit_livestream" protocol requires a well formed request to come
* in via websocket that resembles:
*
* {
* "period_ms": <milliseconds>,
* "check_uuid": "<uuid_string>",
* "metrics" : ["<metric_name1>", "<metric_name2>"]
* }
*
* There can be only one active livestream request for a single websocket at one time.
* However, you can send down a new livestream request at any time to alter the
* stream based on new requirements.
*
* If the "metrics" member exists in the incoming request, then the metrics that are sent will be
* filtered to those that match the strings in the array by exact match. If you want to get
* all metrics in the check, omit the "metrics" member from the request object.
*/
int
noit_websocket_msg_handler(mtev_http_rest_closure_t *restc, int opcode,
const unsigned char *msg, size_t msg_len)
{
#ifdef HAVE_WSLAY
const char *error = NULL;
noit_websocket_closure_t *handler_data = restc->call_closure;
/* for now this message is JSON, that might change in the future */
struct mtev_json_tokener *tok = mtev_json_tokener_new();
struct mtev_json_object *request = mtev_json_tokener_parse_ex(tok, (const char *)msg, msg_len);
enum mtev_json_tokener_error err = tok->err;
mtev_json_tokener_free(tok);
if (err != mtev_json_tokener_success) {
error = "Unable to parse incoming json";
goto websocket_handler_error;
}
uint64_t period_ms = mtev_json_object_get_uint64(mtev_json_object_object_get(request, "period_ms"));
const char *check_uuid = mtev_json_object_get_string(mtev_json_object_object_get(request, "check_uuid"));
struct mtev_json_object *metrics = mtev_json_object_object_get(request, "metrics");
if (handler_data != NULL) {
/* destroy old subscription */
noit_websocket_closure_free(handler_data);
handler_data = NULL;
}
handler_data = restc->call_closure = noit_websocket_closure_alloc();
handler_data->use_filter = mtev_false;
restc->call_closure_free = noit_websocket_closure_free;
handler_data->period = period_ms;
if (metrics != NULL) {
handler_data->use_filter = mtev_true;
handler_data->filter_count = mtev_json_object_array_length(metrics);
handler_data->filters = calloc(sizeof(char *), handler_data->filter_count);
jl_array_list* a = mtev_json_object_get_array(metrics);
for (int i = 0; i < handler_data->filter_count; i++) {
struct mtev_json_object *o = jl_array_list_get_idx(a, i);
if (o != NULL) {
handler_data->filters[i] = strdup(mtev_json_object_get_string(o));
}
}
}
handler_data->restc = restc;
strncpy(handler_data->uuid_str, check_uuid, UUID_STR_LEN);
handler_data->uuid_str[36] = '\0';
if(uuid_parse(handler_data->uuid_str, handler_data->uuid)) {
mtevL(noit_error, "bad uuid received in livestream websocket_handler '%s'\n", handler_data->uuid_str);
error = "bad uuid received in livestream subscription request";
goto websocket_handler_error;
}
mtev_json_object_put(request);
/* setup subscription to noit_livestream */
asprintf(&handler_data->feed, "websocket_livestream/%d", mtev_atomic_inc32(&ls_counter));
handler_data->log_stream = mtev_log_stream_new(handler_data->feed, "noit_websocket_livestream", handler_data->feed,
handler_data, NULL);
handler_data->check = noit_check_watch(handler_data->uuid, handler_data->period);
if(!handler_data->check) {
error = "Cannot locate check";
goto websocket_handler_error;
}
/* This check must be watched from the livestream */
noit_check_transient_add_feed(handler_data->check, handler_data->feed);
/* Note the check */
noit_check_log_check(handler_data->check);
/* kick it off, if it isn't running already */
if(!NOIT_CHECK_LIVE(handler_data->check)) noit_check_activate(handler_data->check);
return 0;
websocket_handler_error:
{
struct mtev_json_object *e = mtev_json_object_new_object();
mtev_json_object_object_add(e, "success", mtev_json_object_new_int(0));
struct mtev_json_object *errors = mtev_json_object_new_array();
struct mtev_json_object *error_o = mtev_json_object_new_object();
mtev_json_object_object_add(error_o, "error", mtev_json_object_new_string(error));
mtev_json_object_array_add(errors, error_o);
mtev_json_object_object_add(e, "errors", errors);
const char *json_error = mtev_json_object_to_json_string(e);
mtev_http_websocket_queue_msg(restc->http_ctx,
WSLAY_TEXT_FRAME | WSLAY_CONNECTION_CLOSE,
(const unsigned char *)json_error, strlen(json_error));
mtev_json_object_put(e);
}
#endif
return -1;
}
