No prefix found at: /opt/conda/envs/...

[andreas-wilm]

Hi there,

Thanks for creating Micromamba and Micromamba Docker!

I followed the instructions to create a Dockerfile and no matter which version I use (0.21.2, 0.21.1, 0.19.0) I get:

error    No prefix found at: /opt/conda/envs/<my-env-name>
critical Aborting.

when running micromamba install -y -f /tmp/env.yml. I also get this when I try to create an environment interactively.

Likewise, if I run a plain micromamba list interactively, I get:

error    Expected environment not found at prefix: /opt/conda
critical Aborting.

I guess I must be doing something fundamentally wrong. Could someone please point the mistake out?

Many thanks,
Andreas

[wholtz]

Hi @andreas-wilm - thank you for your interest in micromamba.

I can reproduce that micromamba list is throwing an error when nothing has been installed in the base environment:

$ docker run -it --rm -v $(pwd):/tmp mambaorg/micromamba:0.21.2 micromamba list
info     ****************** Backtrace Start ******************
debug    Loading configuration
trace    Compute configurable 'create_base'
trace    Compute configurable 'no_env'
trace    Compute configurable 'no_rc'
trace    Compute configurable 'rc_files'
trace    Compute configurable 'root_prefix'
trace    Get RC files configuration from locations up to HomeDir
trace    Configuration not found at '/home/mambauser/.mambarc'
trace    Configuration not found at '/home/mambauser/.condarc'
trace    Configuration not found at '/home/mambauser/.conda/condarc.d'
trace    Configuration not found at '/home/mambauser/.conda/condarc'
trace    Configuration not found at '/home/mambauser/.conda/.condarc'
trace    Configuration not found at '/opt/conda/.mambarc'
trace    Configuration not found at '/opt/conda/condarc.d'
trace    Configuration not found at '/opt/conda/condarc'
trace    Configuration not found at '/opt/conda/.condarc'
trace    Configuration not found at '/var/lib/conda/.mambarc'
trace    Configuration not found at '/var/lib/conda/condarc.d/'
trace    Configuration not found at '/var/lib/conda/condarc'
trace    Configuration not found at '/var/lib/conda/.condarc'
trace    Configuration not found at '/etc/conda/.mambarc'
trace    Configuration not found at '/etc/conda/condarc.d/'
trace    Configuration not found at '/etc/conda/condarc'
trace    Configuration not found at '/etc/conda/.condarc'
trace    Update configurable 'no_env'
trace    Compute configurable 'file_specs'
trace    Compute configurable 'spec_file_env_name'
trace    Compute configurable 'env_name'
trace    Compute configurable 'envs_dirs'
trace    Compute configurable 'use_target_prefix_fallback'
trace    Compute configurable 'target_prefix'
trace    Get RC files configuration from locations up to TargetPrefix
trace    Configuration not found at '/opt/conda/.mambarc'
trace    Configuration not found at '/opt/conda/condarc.d'
trace    Configuration not found at '/opt/conda/condarc'
trace    Configuration not found at '/opt/conda/.condarc'
trace    Configuration not found at '/home/mambauser/.mambarc'
trace    Configuration not found at '/home/mambauser/.condarc'
trace    Configuration not found at '/home/mambauser/.conda/condarc.d'
trace    Configuration not found at '/home/mambauser/.conda/condarc'
trace    Configuration not found at '/home/mambauser/.conda/.condarc'
trace    Configuration not found at '/opt/conda/.mambarc'
trace    Configuration not found at '/opt/conda/condarc.d'
trace    Configuration not found at '/opt/conda/condarc'
trace    Configuration not found at '/opt/conda/.condarc'
trace    Configuration not found at '/var/lib/conda/.mambarc'
trace    Configuration not found at '/var/lib/conda/condarc.d/'
trace    Configuration not found at '/var/lib/conda/condarc'
trace    Configuration not found at '/var/lib/conda/.condarc'
trace    Configuration not found at '/etc/conda/.mambarc'
trace    Configuration not found at '/etc/conda/condarc.d/'
trace    Configuration not found at '/etc/conda/condarc'
trace    Configuration not found at '/etc/conda/.condarc'
trace    Update configurable 'no_env'
trace    Compute configurable 'target_prefix_checks'
error    Expected environment not found at prefix: /opt/conda
critical Aborting.
info     ****************** Backtrace End ********************
$ 

But I'm not able to reproduce an error with micromamba install -y -f /tmp/env.yml

Does the following work for you?

$ cat > env.yml << EOF
name: base
channels:
  - conda-forge
dependencies:
  - jq=1.6
EOF
$ docker run -it --rm -v $(pwd):/tmp mambaorg/micromamba:0.21.2 micromamba install -y -f /tmp/env.yml

If you can post a minimal example with your failing Dockerfile, that would be helpful.

Are you running on x86 hardware? The arm64 and ppc64le images have seen little use and are not as well tested.

[andreas-wilm]

Wow. This is the fastest Github response I've ever seen. Thanks so much.

I'm on an Intel Mac. But turns out the architecture is not the problem, because your simple env.yml file worked flawlessly. I just tried a bit more and it turns out the a hyphen in the environment name caused this. I'm not sure why that is or why the cryptic error message, but without the hyphen everything works as expected.

Apologies. And thank you so much for getting me on the right track

[wholtz]

I'm guessing you had something like this:

$ cat > env.yml << EOF
name: MyEnv
channels:
  - conda-forge
dependencies:
  - jq=1.6
EOF
$ docker run -it --rm -v $(pwd):/tmp mambaorg/micromamba:0.21.2 micromamba install -y -f /tmp/env.yml

This does not work because the env.yml is supplying an environment name that doesn't exist and the install sub-command will not create an environment. Switching the name to base would make it work, as that environment does not need to be explicitly created. Alternatively, you could use the create sub-command:

$ cat > env.yml << EOF
name: MyEnv
channels:
  - conda-forge
dependencies:
  - jq=1.6
EOF
$ docker run -it --rm -v $(pwd):/tmp mambaorg/micromamba:0.21.2 micromamba create -y -f /tmp/env.yml

This form creates the new environment before installing the packages. Hyphens should work in environment names.

[andreas-wilm]

Oh my God. You are right. The hyphen was a red herring, because I tried name: base and name: base-test and the latter wasn't working, but you made it obvious that it doesn't work because the environment doesn't exist. It should have been obvious that I have to use create instead of install. This was stupid. Sorry!