Noarch repodata.json is empty for proxy channels

In our quetz server, we proxy conda-forge into a channel of the same name:

  {
    "name": "conda-forge",
    "description": null,
    "private": true,
    "size_limit": null,
    "ttl": 36000,
    "mirror_channel_url": "https://conda.anaconda.org/conda-forge",
    "mirror_mode": "proxy",
    "members_count": 1,
    "packages_count": 0
  },

Installation often fails because certain packages cannot be found. We narrowed the issue down to the noarch repodata.json being empty. Navigating to /get/conda-forge/noarch/repodata.json yields:

{
  "info": {
    "subdir": "noarch"
  },
  "packages": {},
  "packages.conda": {},
  "repodata_version": 1
}

This problem only occurs for the noarch platform. Also, in our package backend (GCS) we have a cached version of the repodata.json, which is not empty (it’s 55MB large).

Any idea what might be causing this?

[wolfv]

OK, so the bug goes as follows:

• we added a repodata.json.gz file to support returning / streaming gzip compressed files from S3 buckets and similar
• we do initialize every channel with an empty noarch repodata.json because the existence of teh noarch/repodata.json is what marks a channel as “existing”
• apparently we do initialize even a proxy-mirror channel with the static noarch/repodata.json files (including the .gz / .bz2 ones). We should not do that.
• the repodata.json.gz is a quetz-specific extension (and a bit of a workaround for OVH because they don’t properly support setting the Content-Encoding header for a given file)

[janjagusch]

thank you!