From 5b898a7732efb646881bfbfb5e1bf5f058b45105 Mon Sep 17 00:00:00 2001 From: Tomas Tomecek Date: Wed, 12 Jul 2017 04:36:25 +0200 Subject: [PATCH] add connection plugin for buildah (#26170) * add connection plugin for buildah Signed-off-by: Tomas Tomecek * fixup * create a method to invoke buildah * mount container filesystem persistently so we can access it during put and fetch * use copyfile function for copying files Signed-off-by: Tomas Tomecek * revert tests Signed-off-by: Tomas Tomecek * fixup Signed-off-by: Tomas Tomecek * progress (this will be squashed into a single commit before merge) * add docs for the conn plugin * fix issue invoking the integration tests * add a way to invoke commands inside the container as a different user Signed-off-by: Tomas Tomecek * fix shellcheck warning Signed-off-by: Tomas Tomecek --- lib/ansible/plugins/connection/buildah.py | 171 ++++++++++++++++++ test/integration/connection-buildah.yaml | 5 + .../targets/connection_buildah/aliases | 1 + .../targets/connection_buildah/posix.sh | 1 + .../targets/connection_buildah/runme.sh | 7 + .../test_connection.inventory | 12 ++ 6 files changed, 197 insertions(+) create mode 100644 lib/ansible/plugins/connection/buildah.py create mode 100644 test/integration/connection-buildah.yaml create mode 100644 test/integration/targets/connection_buildah/aliases create mode 120000 test/integration/targets/connection_buildah/posix.sh create mode 100755 test/integration/targets/connection_buildah/runme.sh create mode 100644 test/integration/targets/connection_buildah/test_connection.inventory diff --git a/lib/ansible/plugins/connection/buildah.py b/lib/ansible/plugins/connection/buildah.py new file mode 100644 index 00000000000..1901a28af2a --- /dev/null +++ b/lib/ansible/plugins/connection/buildah.py @@ -0,0 +1,171 @@ +# Based on the docker connection plugin +# +# Connection plugin for building container images using buildah tool +# https://github.com/projectatomic/buildah +# +# Written by: Tomas Tomecek (https://github.com/TomasTomecek) +# +# This file is part of Ansible +# +# Ansible 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. +# +# Ansible 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 Ansible. If not, see . + +""" +DOCUMENTATION: + connection: buildah + short_description: interact with an existing buildah container + description: + - Run commands or put/fetch files to an existing container using buildah tool. + author: Tomas Tomecek (ttomecek@redhat.com) + version_added: 2.4 + options: + remote_user: + description: + - User specified via name or ID which is used to execute commands inside the container. + config: + - section: defaults + key: remote_user + env_vars: + - ANSIBLE_REMOTE_USER + host_vars: + - ansible_user +""" + +from __future__ import (absolute_import, division, print_function) + +import shlex +import shutil + +import subprocess + +import ansible.constants as C +from ansible.module_utils._text import to_bytes +from ansible.plugins.connection import ConnectionBase, ensure_connect + + +try: + from __main__ import display +except ImportError: + from ansible.utils.display import Display + display = Display() + + +__metaclass__ = type + + +# this _has to be_ named Connection +class Connection(ConnectionBase): + """ + This is a connection plugin for buildah: it uses buildah binary to interact with the containers + """ + + # String used to identify this Connection class from other classes + transport = 'buildah' + has_pipelining = True + become_methods = frozenset(C.BECOME_METHODS) + + def __init__(self, play_context, new_stdin, *args, **kwargs): + super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs) + + self._container_id = self._play_context.remote_addr + self._connected = False + # container filesystem will be mounted here on host + self._mount_point = None + # `buildah inspect` doesn't contain info about what the default user is -- if it's not + # set, it's empty + self.user = self._play_context.remote_user + + def _set_user(self): + self._buildah(b"config", [b"--user=" + to_bytes(self.user, errors='surrogate_or_strict')]) + + def _buildah(self, cmd, cmd_args=None, in_data=None): + """ + run buildah executable + + :param cmd: buildah's command to execute (str) + :param cmd_args: list of arguments to pass to the command (list of str/bytes) + :param in_data: data passed to buildah's stdin + :return: return code, stdout, stderr + """ + local_cmd = ['buildah', cmd, '--', self._container_id] + if cmd_args: + local_cmd += cmd_args + local_cmd = [to_bytes(i, errors='surrogate_or_strict') for i in local_cmd] + + display.vvv("RUN %s" % (local_cmd,), host=self._container_id) + p = subprocess.Popen(local_cmd, shell=False, stdin=subprocess.PIPE, + stdout=subprocess.PIPE, stderr=subprocess.PIPE) + + stdout, stderr = p.communicate(input=in_data) + stdout = to_bytes(stdout, errors='surrogate_or_strict') + stderr = to_bytes(stderr, errors='surrogate_or_strict') + return p.returncode, stdout, stderr + + def _connect(self): + """ + no persistent connection is being maintained, mount container's filesystem + so we can easily access it + """ + super(Connection, self)._connect() + rc, self._mount_point, stderr = self._buildah("mount") + self._mount_point = self._mount_point.strip() + display.vvvvv("MOUNTPOINT %s RC %s STDERR %r" % (self._mount_point, rc, stderr)) + self._connected = True + + @ensure_connect + def exec_command(self, cmd, in_data=None, sudoable=False): + """ run specified command in a running OCI container using buildah """ + super(Connection, self).exec_command(cmd, in_data=in_data, sudoable=sudoable) + + cmd_bytes = to_bytes(cmd, errors='surrogate_or_strict') + cmd_args_list = shlex.split(cmd_bytes) + + rc, stdout, stderr = self._buildah("run", cmd_args_list) + + display.vvvvv("STDOUT %r STDERR %r" % (stderr, stderr)) + return rc, stdout, stderr + + def put_file(self, in_path, out_path): + """ Place a local file located in 'in_path' inside container at 'out_path' """ + super(Connection, self).put_file(in_path, out_path) + display.vvv("PUT %s TO %s" % (in_path, out_path), host=self._container_id) + + real_out_path = self._mount_point + to_bytes(out_path, errors='surrogate_or_strict') + shutil.copyfile( + to_bytes(in_path, errors='surrogate_or_strict'), + to_bytes(real_out_path, errors='surrogate_or_strict') + ) + # alternatively, this can be implemented using `buildah copy`: + # rc, stdout, stderr = self._buildah( + # "copy", + # [to_bytes(in_path, errors='surrogate_or_strict'), + # to_bytes(out_path, errors='surrogate_or_strict')] + # ) + + def fetch_file(self, in_path, out_path): + """ obtain file specified via 'in_path' from the container and place it at 'out_path' """ + super(Connection, self).fetch_file(in_path, out_path) + display.vvv("FETCH %s TO %s" % (in_path, out_path), host=self._container_id) + + real_in_path = self._mount_point + to_bytes(in_path, errors='surrogate_or_strict') + shutil.copyfile( + to_bytes(real_in_path, errors='surrogate_or_strict'), + to_bytes(out_path, errors='surrogate_or_strict') + ) + + def close(self): + """ unmount container's filesystem """ + super(Connection, self).close() + rc, stdout, stderr = self._buildah("umount") + display.vvvvv("RC %s STDOUT %r STDERR %r" % (rc, stdout, stderr)) + self._connected = False diff --git a/test/integration/connection-buildah.yaml b/test/integration/connection-buildah.yaml new file mode 100644 index 00000000000..336857f932f --- /dev/null +++ b/test/integration/connection-buildah.yaml @@ -0,0 +1,5 @@ +- hosts: buildah-container + connection: buildah + gather_facts: no + roles: + - { role: connection_buildah } diff --git a/test/integration/targets/connection_buildah/aliases b/test/integration/targets/connection_buildah/aliases new file mode 100644 index 00000000000..ca5668ce04e --- /dev/null +++ b/test/integration/targets/connection_buildah/aliases @@ -0,0 +1 @@ +needs/root diff --git a/test/integration/targets/connection_buildah/posix.sh b/test/integration/targets/connection_buildah/posix.sh new file mode 120000 index 00000000000..70aa5dbdba4 --- /dev/null +++ b/test/integration/targets/connection_buildah/posix.sh @@ -0,0 +1 @@ +../connection_posix/test.sh \ No newline at end of file diff --git a/test/integration/targets/connection_buildah/runme.sh b/test/integration/targets/connection_buildah/runme.sh new file mode 100755 index 00000000000..b1acf92376b --- /dev/null +++ b/test/integration/targets/connection_buildah/runme.sh @@ -0,0 +1,7 @@ +#!/usr/bin/env bash + +set -eux + +ANSIBLE_TEST_REMOTE_INTERPRETER='' ./posix.sh "$@" + +ANSIBLE_TEST_REMOTE_INTERPRETER='' ANSIBLE_REMOTE_USER="1000" ./posix.sh "$@" diff --git a/test/integration/targets/connection_buildah/test_connection.inventory b/test/integration/targets/connection_buildah/test_connection.inventory new file mode 100644 index 00000000000..6a3c41f1fe6 --- /dev/null +++ b/test/integration/targets/connection_buildah/test_connection.inventory @@ -0,0 +1,12 @@ +[buildah] +buildah-container ansible_ssh_pipelining=true +[buildah:vars] +# 1. install buildah +# 2. create container: +# $ sudo buildah from --name=buildah-container python:2 +# 3. run test: +# $ ANSIBLE_TEST_REMOTE_INTERPRETER= ansible-test integration --local connection_buildah +# 6. remove container +# $ sudo buildah rm buildah-container +ansible_host=buildah-container +ansible_connection=buildah