Add new type __docker_stack

cdist/conf/type/__docker_stack/explorer/stack-exists

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+#!/bin/sh -e
+#
+# 2018 Ľubomír Kučera <lubomir.kucera.jr at gmail.com>
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+if docker stack ls | grep -q "^${__object_id:?} "; then
+	echo 1
+else
+	echo 0
+fi

cdist/conf/type/__docker_stack/gencode-remote

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+#!/bin/sh -e
+#
+# 2018 Ľubomír Kučera <lubomir.kucera.jr at gmail.com>
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+stack="${__object_id:?}"
+state=$(cat "${__object:?}/parameter/state")
+
+case "${state}" in
+	absent)
+		stack_exists=$(cat "${__object:?}/explorer/stack-exists")
+
+		if [ "${stack_exists}" -ne 1 ]; then
+			exit 0
+		fi
+
+		echo "docker stack rm ${stack}"
+	;;
+	present)
+		compose_file=$(cat "${__object}/parameter/compose-file")
+
+		if [ -z "${compose_file}" ]; then
+			exit 0
+		fi
+
+		if [ "${compose_file}" = "-" ]; then
+			compose_file="${__object}/stdin"
+		fi
+
+		cat <<-EOF
+		compose_file="\$(mktemp cdist.XXXXXXXXXX)"
+
+		base64 -d > "\${compose_file}" << eof
+		$(base64 "${compose_file}")
+		eof
+
+		docker stack deploy --compose-file "\${compose_file}" \
+			--prune ${stack}
+
+		rm "\${compose_file}"
+		EOF
+	;;
+	*)
+		echo "Unsupported state: ${state}" >&2
+
+		exit 1
+	;;
+esac

cdist/conf/type/__docker_stack/man.rst

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+cdist-type__docker_stack(7)
+===========================
+
+NAME
+----
+
+cdist-type__docker_stack - Manage Docker stacks
+
+DESCRIPTION
+-----------
+
+This type manages service stacks.
+
+.. note::
+    Since there is no easy way to tell whether a stack needs to be updated,
+    `docker stack deploy` is being run every time this type is invoked.
+    However, it does not mean this type is not idempotent. If Docker does not
+    detect changes, the existing stack will not be updated.
+
+OPTIONAL PARAMETERS
+-------------------
+
+compose-file
+    Path to the compose file. If it is '-' (dash), read standard input.
+
+state
+    'present' or 'absent', defaults to 'present' where:
+
+    present
+        the stack is deployed
+    absent
+        the stack is removed
+
+EXAMPLES
+--------
+
+.. code-block:: sh
+
+    # Deploys 'foo' stack defined in 'docker-compose.yml' compose file
+    __docker_stack foo --compose-file docker-compose.yml
+
+
+AUTHORS
+-------
+
+Ľubomír Kučera <lubomir.kucera.jr at gmail.com>
+
+COPYING
+-------
+
+Copyright \(C) 2018 Ľubomír Kučera. 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.

cdist/conf/type/__docker_stack/parameter/default/state

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+present

cdist/conf/type/__docker_stack/parameter/optional

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+compose-file
+state