/**
* Parses a query string "m=metric{tagk1=tagv1,...}" type query and returns a tsuid.
*
* @param data_query The query we're building
* @throws BadRequestException if we are unable to parse the query or it is missing components
* @todo - make this asynchronous
*/
private String getTSUIDForMetric(final String query_string, TSDB tsdb) {
if (query_string == null || query_string.isEmpty()) {
throw new BadRequestException("The query string was empty");
}
// m is of the following forms:
// metric[{tag=value,...}]
// where the parts in square brackets `[' .. `]' are optional.
final HashMap<String, String> tags = new HashMap<String, String>();
String metric = null;
try {
metric = Tags.parseWithMetric(query_string, tags);
} catch (IllegalArgumentException e) {
throw new BadRequestException(e);
}
// sort the UIDs on tagk values
final ByteMap<byte[]> tag_uids = new ByteMap<byte[]>();
for (final Entry<String, String> pair : tags.entrySet()) {
tag_uids.put(
tsdb.getUID(UniqueIdType.TAGK, pair.getKey()),
tsdb.getUID(UniqueIdType.TAGV, pair.getValue()));
}
// Byte Buffer to generate TSUID, pre allocated to the size of the TSUID
final ByteArrayOutputStream buf =
new ByteArrayOutputStream(
TSDB.metrics_width() + tag_uids.size() * (TSDB.tagk_width() + TSDB.tagv_width()));
try {
buf.write(tsdb.getUID(UniqueIdType.METRIC, metric));
for (final Entry<byte[], byte[]> uids : tag_uids.entrySet()) {
buf.write(uids.getKey());
buf.write(uids.getValue());
}
} catch (IOException e) {
throw new BadRequestException(e);
}
final String tsuid = UniqueId.uidToString(buf.toByteArray());
return tsuid;
}
/**
* Get the next random UID. Right now it uses 3 bytes as the metric with is 3. If it is 3 then it
* can return only upto the max value a 3 byte integer can return, which is 2^31-1. In that case,
* even though it is long, its range will be between 0 and 2^31-1
*
* @return random UID
*/
public static long getRandomUID() {
return getRandomUID(TSDB.metrics_width());
}