Install cp2k from conda-forge (#170)

Installing CP2K from conda provides an easy way to change the CP2K version and
greatly reduces the size of the Dockerfile used for testing.

Using the `mamba` installer allows keeping the installation time low.

.docker/cp2k-code.yml

@@ -2,6 +2,8 @@ label: cp2k
 computer: localhost
 description:
 default_calc_job_plugin: cp2k
-filepath_executable: /usr/bin/cp2k
+filepath_executable: /opt/conda/envs/cp2k/bin/cp2k.psmp
 append_text:
-prepend_text:
+prepend_text: |
+  eval "$(command conda shell.bash hook 2> /dev/null)"
+  conda activate cp2k

Dockerfile

@@ -9,21 +9,19 @@ ARG AIIDA_VERSION=2.5.0
 
 FROM aiidateam/aiida-core-with-services:${AIIDA_VERSION}
 
+
 # To prevent the container to exit prematurely.
 ENV KILL_ALL_RPOCESSES_TIMEOUT=50
 
-
 USER root
-# Install statically linked CP2K which is a considerably newer release than Debian builtin.
-# The statically linked CP2K is a non-MPI binary, but we're running all tests with 1 MPI proc.
 RUN set -ex ; \
   apt-get update ; \
-  apt-get install -y --no-install-recommends openmpi-bin locate; \
-  wget --no-verbose -O /usr/bin/cp2k https://github.com/cp2k/cp2k/releases/download/v8.2.0/cp2k-8.2-Linux-x86_64.ssmp ; \
-  echo "1e6fccf901873ebe9c827f45fb29331f599772f6e6281e988d8956c7a3aa143c /usr/bin/cp2k" | sha256sum -c ; \
-  chmod +x /usr/bin/cp2k
+  apt-get install -y --no-install-recommends libsymspg1
 
 USER aiida
+
+RUN mamba create --yes -c conda-forge -n cp2k cp2k=9.1 && mamba clean --all -f -y
+
 # Install aiida-cp2k plugin.
 COPY --chown="${SYSTEM_UID}:${SYSTEM_GID}" . /home/aiida/aiida-cp2k
 RUN pip install ./aiida-cp2k[dev,docs]

conftest.py

@@ -6,7 +6,11 @@
 
 @pytest.fixture(scope="function")
 def cp2k_code(aiida_local_code_factory):
-    return aiida_local_code_factory("cp2k", "cp2k")
+    return aiida_local_code_factory(
+        entry_point="cp2k",
+        executable="/opt/conda/envs/cp2k/bin/cp2k.psmp",
+        prepend_text='eval "$(command conda shell.bash hook 2> /dev/null)"\nconda activate cp2k\n',
+    )
 
 
 @pytest.fixture(scope="function", autouse=True)