Created attachment 864634 [details]
Fix

Building a container from a Spack-generated Dockerfile fails with the error
message:
[1/2] STEP 3/5: RUN cd /opt/spack-environment && spack env activate . && spack
install --fail-fast && spack gc -y
/bin/sh: spack: command not found
Error: building at STEP "RUN cd /opt/spack-environment && spack env activate .
&& spack install --fail-fast && spack gc -y": while running runtime: exit
status 127

Reason:
The 'RUN' command does not source /opt/spack/share/spack/setup-env.sh before
calling spack which conveniently sets up PATH (among other things) to include
the spack binary.
Even with spack in the search path, `spack env activate .` would fail without
the environment set up.

There are two locations in the Dockerfile-template where this needs to be
added.

The singularityfile template does this correctly already.