* tsdb: don't allow ingesting empty labelsets
When we ingest an empty labelset in the head, further blocks can not be
compacted, with the error:
```
level=error ts=2020-02-27T21:26:58.379Z caller=db.go:659 component=tsdb
msg="compaction failed" err="persist head block: write compaction:
add series: out-of-order series added with label set \"{}\" / prev:
\"{}\""
```
We should therefore reject those invalid empty labelsets upfront.
This can be reproduced with the following:
```
cat << END > prometheus.yml
scrape_configs:
- job_name: 'prometheus'
scrape_interval: 1s
basic_auth:
username: test
password: test
metric_relabel_configs:
- regex: ".*"
action: labeldrop
static_configs:
- targets:
- 127.0.1.1:9090
END
./prometheus --storage.tsdb.min-block-duration=1m
```
And wait a few minutes.
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
* promparse: sort all labels when parsing
Some label names might start with an uppercase letter in which case it
needs to come before __name__. Without this it means that we are not
maintaining the same invariant that all label names should be sorted in
such cases.
Amend the tests to check this problem automatically. Without the change
the tests do not pass.
Signed-off-by: Giedrius Statkevičius <giedriuswork@gmail.com>
This is based on the existing parser, and has slightly better
performance (few %) than it.
Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
Pass content type down to text parser.
Add layer of indirection in front of text parser,
and rename to avoid future clashes.
Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
Julien Pivotto
Brian Brazil
Bartek Plotka
Chris Marchbanks
Giedrius Statkevičius