Build fails when creating conda env

[nicrie]

Details

• Read the Docs project URL: https://readthedocs.org/projects/xeofs/
• Build URL (if applicable): https://readthedocs.org/projects/xeofs/builds/17851802/
• Read the Docs username (if applicable): https://readthedocs.org/profiles/nrieger/

Expected Result

Building package documentation.

Actual Result

Build fails when creating the conda environment necessary for my project. It did work in the past when I did the last project update.

readthedocs.yaml

version: 2

sphinx:
   configuration: docs/conf.py


conda:
  environment: docs/environment.yml

environment.yml

name: xeofs
channels:
  - conda-forge
  - defaults
dependencies:
  - python>3.8
  - numpy
  - pandas
  - xarray
  - conda
  - scikit-learn
  - yaml
  - matplotlib
  - seaborn
  - pip:
    - sphinxawesome-theme
    - git+https://github.com/sphinx-gallery/sphinx-gallery.git@master
    - xeofs

[ctb]

we saw this over in sourmash, too - sourmash-bio/sourmash#2227. Issue text copy/pasted below :).

---

we're getting the following error on readthedocs builds as of about 8 hours ago -

%  conda env create --quiet --name 2225 --file doc/environment.yml 
 Collecting package metadata: ...working... failed

UnavailableInvalidChannel: The channel is not accessible or is invalid.
  channel name: pkgs/main
  channel url: https://repo.anaconda.com/pkgs/main
  error code: 404

You will need to adjust your conda configuration to proceed.
Use `conda config --show channels` to view your configuration's current state,
and use `conda config --show-sources` to view config file locations.

while this channel is not in our doc/environment.yml it looks like it might be something added by RTD, based on free-associating from #8059.

Reading https://server-docs.anaconda.com/en/latest/reference/troubleshooting.html, it appears that anaconda might be blocking the readthedocs build server from accessing that channel - possible reasons given, in order of likelihood, are -

The user has misconfigured their channels in their configuration (for example, the secure location where the token is stored was accidentally deleted (most common)

A firewall or other security device or system is preventing user access (second most common)

We are blocking their access because of a potential terms of service violation (third most common)

I'm not going to do anything more to troubleshoot it just yet, maybe it'll get fixed over the weekend or something...

[nicrie]

I confirm that this seems like the same error. While reading through the possible reasons, I came back to my mind that I did update my SSH key which I use to connect to git/pypi.

The user has misconfigured their channels in their configuration (for example, the secure location where the token is stored was > accidentally deleted (most common)

Perhaps this is indeed the reason, however, it surprises me that building the conda environment fails when - to me - it seems more likely that the process of publishing it to pypi would raise an error.

[maresb]

If all your packages are available on conda-forge, you may be able to change defaults to nodefaults to avoid querying the URL which results in the 404. See the (!) Tip here.

[nicrie]

thanks @maresb for me that did the trick! :)

[humitos]

Hi all and thanks for reporting this issue. I ran some tests to try to debug this deeper and find out a solution.

• Project: test-builds
• Version: conda-env-py3.7

On Read the Docs

I triggered a build for this project, https://readthedocs.org/projects/test-builds/builds/17859242/ and the build failed with the error reported in the description.

$ conda env create --quiet --name conda-env-py3.7 --file environment.yml
 Warning: you have pip-installed dependencies in your environment file, but you do not list pip itself as one of your conda dependencies.  Conda may not use the correct pip to install your packages, and they may end up in the wrong place.  Please add an explicit pip dependency.  I'm adding one for you, but still nagging you.
Collecting package metadata: ...working... failed

UnavailableInvalidChannel: The channel is not accessible or is invalid.
  channel name: pkgs/main
  channel url: https://repo.anaconda.com/pkgs/main
  error code: 404

You will need to adjust your conda configuration to proceed.
Use `conda config --show channels` to view your configuration's current state,
and use `conda config --show-sources` to view config file locations. 

On local shell

I ran the commands locally and it works just fine. The environment was created without issues.

On local Read the Docs instance

I triggered a build for the same project and version in my local Read the Docs instance and it worked properly. The environment was created without issues and the build succeeded.

[humitos]

• I ran a similar test but using Mamba instead, and it worked: https://readthedocs.org/projects/test-builds/builds/17859367/
• I updated my project to use Read the Docs config file v2 and build.tools.python: miniconda3-4.7 at https://readthedocs.org/projects/test-builds/builds/17859407/ and it worked fine. See the required changes at readthedocs/test-builds@e174713

---

After these tests, I guess what is happening here is that the Conda version used on Read the Docs ¹ is old and it's pointing to an obsolete/deprecated URL for the default channel (see https://server-docs.anaconda.com/en/latest/reference/troubleshooting.html#conda-channel-is-unavailable-missing-or-package-itself-is-missing)

I would suggest you all to upgrade your config file to use build.tools.python: miniconda3-4.7 (see https://docs.readthedocs.io/en/stable/config-file/v2.html#build-tools-python) and build.os: ubuntu-22.04 (see https://docs.readthedocs.io/en/stable/config-file/v2.html#build-os). I guess that will fix your issue.

Please, if you follow this suggestion, let me know if it works for you.

Footnotes

1. this is only happening on readthedocs/build:latest image, tho. Newer images do not have this problem. ↩

[ctb]

that seems to have worked for us, thank you! sourmash-bio/sourmash#2231

[humitos]

We have documented how users can upgrade the conda version manually in case they require it: https://docs.readthedocs.io/en/latest/build-customization.html#update-conda-version