swarm: convert cylc-dev Docker image to run on ubuntu:latest

* Switch from miniconda to micromamba for faster builds.
* Change the base image of cylc-dev from miniconda to ubunutu.

.dockerignore

@@ -9,3 +9,4 @@ __pycache__
 !cylc
 !dockerfiles/*
 !setup*
+!MANIFEST.in

dockerfiles/cylc-dev/Dockerfile

@@ -1,51 +1,49 @@
-# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
-# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
-#
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-FROM conda/miniconda3:latest
-
-LABEL version="1.0" \
-      description="Image with Cylc installed with Conda from a working copy."
-
-ARG CONDA_ENV="cylc-dev"
-ARG CYLC_FLOW_DIR="./"
-
-# suppress bizarre error messages
-# mesg: ttyname failed: Inappropriate ioctl for device
-RUN sed -i 's/mesg.*/tty -s \&\& &/' "$HOME/.profile"
-
-# copy in cylc source files
-COPY "$CYLC_FLOW_DIR" "cylc"
-
-# install cylc dependencies
-RUN apt-get update && \
-    # build-deps: build-essential
-    # run deps: procps, rsync
-    apt-get -qq -y install build-essential procps rsync tree && \
-    # install conda stuff
-    conda init bash && \
-    . ./usr/local/etc/profile.d/conda.sh && \
-    conda env create -n "${CONDA_ENV}" -f './cylc/conda-environment.yml' && \
-    conda clean -y --all && \
-    apt-get -y remove build-essential && \
-    apt-get autoclean && \
-    echo "conda activate $CONDA_ENV" >> $HOME/.bashrc && \
-    # tests require TMPDIR
+# 1) The Mamba image
+#    This image has mamba installed, we use it to create and pack
+#    the required Conda environment.
+FROM mambaorg/micromamba AS mamba
+
+# create the environment
+COPY conda-environment.yml .
+RUN micromamba env create -f conda-environment.yml --prefix ./env
+
+# pack the environment
+RUN \
+    micromamba create -c conda-forge -n conda-pack conda-pack && \
+    micromamba run -n conda-pack conda-pack --prefix ./env -o ./packed-env.tar && \
+    pwd && \
+    mkdir ./venv && \
+    cd ./venv && \
+    tar -xf ../packed-env.tar && \
+    rm ../packed-env.tar
+
+
+# 2) The Cylc image
+#    This has the Cylc Mamba environment installed and activated by default in
+#    Bash shells. However, it does not have Mamba installed.
+FROM ubuntu:latest as cylc-dev
+
+COPY --from=mamba /tmp/venv /venv
+COPY ./ /cylc
+
+SHELL ["/bin/bash", "-c", "-l"]
+ENTRYPOINT /bin/bash
+
+# wipe the default crud then auto-activate the Cylc Mamba environment
+RUN \
+    rm $HOME/.bashrc && \
+    echo '. /venv/bin/activate' >> $HOME/.bashrc && \
     echo "export TMPDIR=/tmp" >> $HOME/.bashrc
 
-# run setup logic
-RUN . $HOME/.bashrc && \
-    pip install -e ./cylc[all] && \
-    cylc version
+# unpack the Mamba environment, then install Cylc into it from source
+RUN \
+    /venv/bin/conda-unpack && \
+    pip install --no-deps -e /cylc coverage && \
+    pip cache purge && \
+    cylc version --long
+
+# install system dependencies
+RUN \
+    apt-get update && \
+    apt-get -qq -y install procps rsync tree at && \
+    apt-get autoclean

dockerfiles/cylc-remote/Dockerfile

@@ -20,14 +20,16 @@ LABEL version="1.0" \
       description="Cylc remote job host for background & at jobs."
 
 # install deps
-RUN apt-get -qq -y install at ssh && \
+RUN  \
+    apt-get -qq -y install ssh iputils-ping && \
     apt-get autoclean
 
 # copy public ssh key (don't setup two way ssh)
 COPY .docker-ssh-keys/*.pub .ssh/
 
 # authorise that key
-RUN mkdir ~/.ssh -p && \
+RUN \
+    mkdir ~/.ssh -p && \
     chmod 700 ~/.ssh && \
     touch ~/.ssh/authorized_keys && \
     chmod 600 ~/.ssh/authorized_keys && \
@@ -40,7 +42,8 @@ EXPOSE 22
 COPY dockerfiles/cylc-remote/configure bin/host-configure
 
 # configure on boot and start the required services
-ENTRYPOINT service ssh start && \
+ENTRYPOINT \
+    service ssh start && \
     atd && \
     /bin/host-configure && \
     /usr/bin/env bash