compactor: weird directory structure

[Reamer]

Thanos, Prometheus and Golang version used:

/ $ /bin/thanos --version
thanos, version 0.8.1 (branch: HEAD, revision: a328f4562f77deefcd990330681a62f7de049e67)
  build user:       root@my_company-thanos-1-build
  build date:       20191016-07:10:48
  go version:       go1.13.1

Object Storage Provider:
S3 with a minio setup

What happened:
Compaction directory structure is weird when a label includes a /. The additional / produces a subfolder.

ls -l /data/compact/
total 20
drwxr-sr-x    4 10003300 10003300      4096 Oct 17 13:03 0@{cluster="s-openshift.my_company.de",prometheus="openshift-monitoring
drwxr-sr-x    4 10003300 10003300      4096 Oct 17 13:03 300000@{cluster="s-openshift.my_company.de",prometheus="openshift-monitoring
drwxr-sr-x    4 10003300 10003300      4096 Oct 17 13:03 3600000@{cluster="s-openshift.my_company.de",prometheus="openshift-monitoring

What you expected to happen:

A nice folder without weird subfolders to chunks

ls -l /data/compact/3600000@{cluster="s-openshift.my_company.de",prometheus="openshift-monitoring/my_company",prometheus_replica="_agg_replica_"}:
total 36
drwxr-sr-x    2 10003300 10003300      4096 Oct 17 13:03 01DQC4N9T0YNFZZR27RD5GCAG5
drwxr-sr-x    2 10003300 10003300      4096 Oct 17 13:03 01DQC4PQ6NTRH3BJYQGJ1S6CKK
drwxr-sr-x    2 10003300 10003300      4096 Oct 17 13:03 01DQC4R5NBDYY241MHJW0MN74D
drwxr-sr-x    2 10003300 10003300      4096 Oct 17 13:03 01DQC4SYR49E14SAN1245ZZZA2
drwxr-sr-x    2 10003300 10003300      4096 Oct 17 13:03 01DQC4VGDG3Y9YS46FZTZ9EPJR
drwxr-sr-x    2 10003300 10003300      4096 Oct 17 13:03 01DQC4WYWR0ZY2PR6ZTXTHJQ1C
drwxr-sr-x    2 10003300 10003300      4096 Oct 17 13:03 01DQC4YB870WD2X7DD9V09SYGG

How to reproduce it (as minimally and precisely as possible):

• Create a Prometheus cluster with prometheus-operator and thanos
• start a compaction
• check folder structure

Anything else we need to know:

I think, at the moment it doesn't affect the functionality

[bwplotka]

Thanks for reporting!

Wow, it is interesting indeed (: I fixed it here: #1666

It should not have any bad consequences, but still, it's safer to sanitize that. Now it will be resolution@hash.