synapse/debian/build_virtualenv

#!/bin/bash
#
# runs dh_virtualenv to build the virtualenv in the build directory,
# and then runs the trial tests against the installed synapse.

set -e

export DH_VIRTUALENV_INSTALL_ROOT=/opt/venvs

# make sure that the virtualenv links to the specific version of python, by
# dereferencing the python3 symlink.
#
# Otherwise, if somebody tries to install (say) the stretch package on buster,
# they will get a confusing error about "No module named 'synapse'", because
# python won't look in the right directory. At least this way, the error will
# be a *bit* more obvious.
#
SNAKE=$(readlink -e /usr/bin/python3)

# try to set the CFLAGS so any compiled C extensions are compiled with the most
# generic as possible x64 instructions, so that compiling it on a new Intel chip
# doesn't enable features not available on older ones or AMD.
#
# TODO: add similar things for non-amd64, or figure out a more generic way to
# do this.

case $(dpkg-architecture -q DEB_HOST_ARCH) in
    amd64)
        export CFLAGS=-march=x86-64
        ;;
esac

# Manually install Poetry and export a pip-compatible `requirements.txt`
TEMP_VENV="$(mktemp -d)"
python3 -m venv "$TEMP_VENV"
source "$TEMP_VENV/bin/activate"
pip install -U pip
pip install poetry==1.3.2
poetry export \
    --extras all \
    --extras test \
    --extras systemd \
    -o exported_requirements.txt
deactivate
rm -rf "$TEMP_VENV"

# Use --no-deps to only install pinned versions in exported_requirements.txt,
# and to avoid https://github.com/pypa/pip/issues/9644
dh_virtualenv \
    --install-suffix "matrix-synapse" \
    --builtin-venv \
    --python "$SNAKE" \
    --upgrade-pip \
    --preinstall="lxml" \
    --preinstall="mock" \
    --preinstall="wheel" \
    --extra-pip-arg="--no-deps" \
    --extra-pip-arg="--no-cache-dir" \
    --extra-pip-arg="--compile" \
    --extras="all,systemd,test" \
    --requirements="exported_requirements.txt"

PACKAGE_BUILD_DIR="$(pwd)/debian/matrix-synapse-py3"
VIRTUALENV_DIR="${PACKAGE_BUILD_DIR}${DH_VIRTUALENV_INSTALL_ROOT}/matrix-synapse"
TARGET_PYTHON="${VIRTUALENV_DIR}/bin/python"

case "$DEB_BUILD_OPTIONS" in
    *nocheck*)
        # Skip running tests if "nocheck" present in $DEB_BUILD_OPTIONS
        ;;

    *)
        # Copy tests to a temporary directory so that we can put them on the
        # PYTHONPATH without putting the uninstalled synapse on the pythonpath.
        tmpdir=$(mktemp -d)
        trap 'rm -r $tmpdir' EXIT

        cp -r tests "$tmpdir"

        # To avoid pulling in the unbuilt Synapse in the local directory
        pushd /

        PYTHONPATH="$tmpdir" \
            "${TARGET_PYTHON}" -m twisted.trial --reporter=text -j2 tests

        popd

        ;;
esac

# build the config file
"${TARGET_PYTHON}" "${VIRTUALENV_DIR}/bin/generate_config" \
        --config-dir="/etc/matrix-synapse" \
        --data-dir="/var/lib/matrix-synapse" |
    perl -pe '
# tweak the paths to the tls certs and signing keys
/^tls_.*_path:/ and s/SERVERNAME/homeserver/;
/^signing_key_path:/ and s/SERVERNAME/homeserver/;

# tweak the pid file location
/^pid_file:/ and s#:.*#: "/var/run/matrix-synapse.pid"#;

# tweak the path to the log config
/^log_config:/ and s/SERVERNAME\.log\.config/log.yaml/;

# tweak the path to the media store
/^media_store_path:/ and s#/media_store#/media#;

# remove the server_name setting, which is set in a separate file
/^server_name:/ and $_ = "#\n# This is set in /etc/matrix-synapse/conf.d/server_name.yaml for Debian installations.\n# $_";

# remove the report_stats setting, which is set in a separate file
/^# report_stats:/ and $_ = "";

' > "${PACKAGE_BUILD_DIR}/etc/matrix-synapse/homeserver.yaml"

# build the log config file
"${TARGET_PYTHON}" "${VIRTUALENV_DIR}/bin/generate_log_config" \
        --output-file="${PACKAGE_BUILD_DIR}/etc/matrix-synapse/log.yaml"

# add a dependency on the right version of python to substvars.
PYPKG=$(basename "$SNAKE")
echo "synapse:pydepends=$PYPKG" >> debian/matrix-synapse-py3.substvars


# add a couple of triggers.  This is needed so that dh-virtualenv can rebuild
# the venv when the system python changes (see
# https://dh-virtualenv.readthedocs.io/en/latest/tutorial.html#step-2-set-up-packaging-for-your-project)
#
# we do it here rather than the more conventional way of just adding it to
# debian/matrix-synapse-py3.triggers, because we need to add a trigger on the
# right version of python.
cat >>"debian/.debhelper/generated/matrix-synapse-py3/triggers" <<EOF
# triggers for dh-virtualenv
interest-noawait $SNAKE
interest dh-virtualenv-interpreter-update

EOF