Add helper script to run integration tests on a Docker container

When running the integration tests through "run.sh" the parent directory
of the Spreed application must be the "apps" directory of an installed
Nextcloud server. Running the tests modifies the configuration and
database of that server, and the tests could fail too if the state of
its database conflicts with that expected by the tests.

The new "run-docker.sh" is a wrapper around "run.sh" that copies the
code (but not the configuration or data) of the Nextcloud server and its
applications to a Docker container, installs the Nextcloud server inside
the container (with a SQLite database), and then executes the
integration tests on the fresh server. This prevents the integration
tests from messing with the original Nextcloud server, and also ensures
that the integration tests will be run with a known initial state.

Besides that, when calling "run-docker.sh" the Docker image to be used
can be specified, so the tests can be easily run on PHP 5.6 or PHP 7.1
using "run-docker.sh --image nextcloudci/phpX.Y:phpX.Y-Z". If the
"--image" option is not given by default the image
"nextcloudci/php7.1:php7.1-15" will be used.

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>

tests/integration/run-docker.sh

@@ -0,0 +1,157 @@
+#!/usr/bin/env bash
+
+# @copyright Copyright (c) 2017, Daniel Calviño Sánchez (danxuliu@gmail.com)
+#
+# @license GNU AGPL version 3 or any later version
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Helper script to run the integration tests on a fresh Nextcloud server through
+# Docker.
+#
+# The integration tests are run in its own Docker container; the grand-grand-
+# grandparent directory of the integration tests directory (that is, the root
+# directory of the Nextcloud server, as it is assumed that the parent directory
+# of this application is the "apps" directory of a Nextcloud server) is copied
+# to the container and the integration tests are run inside it; in the container
+# the configuration/data from the original Nextcloud server is ignored, and a
+# new server installation is performed inside the container instead. Once the
+# tests end the container is stopped.
+#
+# To perform its job, the script requires the "docker" command to be available.
+#
+# The Docker Command Line Interface (the "docker" command) requires special
+# permissions to talk to the Docker daemon, and those permissions are typically
+# available only to the root user. Please see the Docker documentation to find
+# out how to give access to a regular user to the Docker daemon:
+# https://docs.docker.com/engine/installation/linux/linux-postinstall/
+#
+# Note, however, that being able to communicate with the Docker daemon is the
+# same as being able to get root privileges for the system. Therefore, you must
+# give access to the Docker daemon (and thus run this script as) ONLY to trusted
+# and secure users:
+# https://docs.docker.com/engine/security/security/#docker-daemon-attack-surface
+#
+# Finally, take into account that this script will automatically remove the
+# Docker container named "nextcloud-local-test-integration-spreed", even if the
+# script did not create it (probably you will not have containers nor images
+# with that name, but just in case).
+
+# Sets the variables that abstract the differences in command names and options
+# between operating systems.
+#
+# Switches between mktemp on GNU/Linux and gmktemp on macOS.
+function setOperatingSystemAbstractionVariables() {
+	case "$OSTYPE" in
+		darwin*)
+			if [ "$(which gtimeout)" == "" ]; then
+				echo "Please install coreutils (brew install coreutils)"
+				exit 1
+			fi
+
+			MKTEMP=gmktemp
+			;;
+		linux*)
+			MKTEMP=mktemp
+			;;
+		*)
+			echo "Operating system ($OSTYPE) not supported"
+			exit 1
+			;;
+	esac
+}
+
+# Creates a Docker container to run the integration tests.
+#
+# This function starts a Docker container with a copy of the Nextcloud code from
+# the grand-grand-grandparent directory, although ignoring any configuration or
+# data that it may provide (for example, if that directory was used directly to
+# deploy a Nextcloud instance in a web server). As the Nextcloud code is copied
+# to the container instead of referenced the original code can be modified while
+# the integration tests are running without interfering in them.
+function prepareDocker() {
+	NEXTCLOUD_LOCAL_CONTAINER=nextcloud-local-test-integration-spreed
+
+	echo "Starting the Nextcloud container"
+	# When using "nextcloudci/phpX.Y" images the container exits immediately if
+	# no command is given, so a Bash session is created to prevent that.
+	docker run --detach --name=$NEXTCLOUD_LOCAL_CONTAINER --interactive --tty $NEXTCLOUD_LOCAL_IMAGE bash
+
+	# Use the $TMPDIR or, if not set, fall back to /tmp.
+	NEXTCLOUD_LOCAL_TAR="$($MKTEMP --tmpdir="${TMPDIR:-/tmp}" --suffix=.tar nextcloud-local-XXXXXXXXXX)"
+
+	# Setting the user and group of files in the tar would be superfluous, as
+	# "docker cp" does not take them into account (the extracted files are set
+	# to root).
+	echo "Copying local Git working directory of Nextcloud to the container"
+	tar --create --file="$NEXTCLOUD_LOCAL_TAR" --exclude=".git" --exclude="./build" --exclude="./config/config.php" --exclude="./data" --exclude="./data-autotest" --exclude="./tests" --directory=../../../../ .
+
+	docker exec $NEXTCLOUD_LOCAL_CONTAINER mkdir /nextcloud
+	docker cp - $NEXTCLOUD_LOCAL_CONTAINER:/nextcloud/ < "$NEXTCLOUD_LOCAL_TAR"
+
+	echo "Installing Nextcloud in the container"
+	docker exec $NEXTCLOUD_LOCAL_CONTAINER bash -c "cd nextcloud && php occ maintenance:install --admin-pass=admin"
+}
+
+# Removes/stops temporal elements created/started by this script.
+function cleanUp() {
+	# Disable (yes, "+" disables) exiting immediately on errors to ensure that
+	# all the cleanup commands are executed (well, no errors should occur during
+	# the cleanup anyway, but just in case).
+	set +o errexit
+
+	echo "Cleaning up"
+
+	if [ -f "$NEXTCLOUD_LOCAL_TAR" ]; then
+		echo "Removing $NEXTCLOUD_LOCAL_TAR"
+	    rm $NEXTCLOUD_LOCAL_TAR
+	fi
+
+	# The name filter must be specified as "^/XXX$" to get an exact match; using
+	# just "XXX" would match every name that contained "XXX".
+	if [ -n "$(docker ps --all --quiet --filter name="^/$NEXTCLOUD_LOCAL_CONTAINER$")" ]; then
+		echo "Removing Docker container $NEXTCLOUD_LOCAL_CONTAINER"
+		docker rm --volumes --force $NEXTCLOUD_LOCAL_CONTAINER
+	fi
+}
+
+# Exit immediately on errors.
+set -o errexit
+
+# Execute cleanUp when the script exits, either normally or due to an error.
+trap cleanUp EXIT
+
+# Ensure working directory is script directory, as some actions (like copying
+# the Git working directory to the container) expect that.
+cd "$(dirname $0)"
+
+# "--image XXX" option can be provided to set the Docker image to use to run
+# the integration tests (one of the "nextcloudci/phpX.Y:phpX.Y-Z" images).
+NEXTCLOUD_LOCAL_IMAGE="nextcloudci/php7.1:php7.1-15"
+if [ "$1" = "--image" ]; then
+	NEXTCLOUD_LOCAL_IMAGE=$2
+
+	shift 2
+fi
+
+# If no parameter is provided to this script all the integration tests are run.
+SCENARIO_TO_RUN=$1
+
+setOperatingSystemAbstractionVariables
+
+prepareDocker
+
+echo "Running tests"
+# --tty is needed to get colourful output.
+docker exec --tty $NEXTCLOUD_LOCAL_CONTAINER bash -c "cd nextcloud/apps/spreed/tests/integration && ./run.sh $SCENARIO_TO_RUN"