remote code execution and tests

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>

lib/cdist/exec/remote.py

@@ -0,0 +1,132 @@
+# -*- coding: utf-8 -*-
+#
+# 2011 Steven Armstrong (steven-cdist at armstrong.cc)
+# 2011 Nico Schottelius (nico-cdist at schottelius.org)
+#
+# 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/>.
+#
+#
+
+import io
+import os
+import sys
+import subprocess
+import logging
+
+import cdist
+
+
+class RemoteScriptError(cdist.Error):
+    def __init__(self, script, command, script_content):
+        self.script = script
+        self.command = command
+        self.script_content = script_content
+
+    def __str__(self):
+        return "Remote script execution failed: %s %s" % (self.script, self.command)
+
+
+class Remote(object):
+    """Execute commands remotely.
+
+    All interaction with the remote side should be done through this class.
+    Directly accessing the remote side from python code is a bug.
+
+    """
+    def __init__(self, target_host, remote_base_path, remote_exec, remote_copy):
+        self.target_host = target_host
+        self.base_path = remote_base_path
+        self._exec = remote_exec
+        self._copy = remote_copy
+
+        self.conf_path = os.path.join(self.base_path, "conf")
+        self.object_path = os.path.join(self.base_path, "object")
+
+        self.type_path = os.path.join(self.conf_path, "type")
+        self.global_explorer_path = os.path.join(self.conf_path, "explorer")
+
+        self.log = logging.getLogger(self.target_host)
+    
+    def create_directories(self):
+        self.rmdir(self.base_path)
+        self.mkdir(self.base_path)
+        self.mkdir(self.conf_path)
+
+    def rmdir(self, path):
+        """Remove directory on the remote side."""
+        self.log.debug("Remote rmdir: %s", path)
+        self.run(["rm", "-rf",  path])
+
+    def mkdir(self, path):
+        """Create directory on the remote side."""
+        self.log.debug("Remote mkdir: %s", path)
+        self.run(["mkdir", "-p", path])
+
+    def transfer(self, source, destination):
+        """Transfer a file or directory to the remote side."""
+        self.log.debug("Remote transfer: %s -> %s", source, destination)
+        self.rmdir(destination)
+        command = self._copy.split()
+        command.extend(["-r", source, self.target_host + ":" + destination])
+        self.run_command(command)
+
+    def run(self, command, env=None):
+        """Run the given command with the given environment on the remote side.
+        Return the output as a string.
+
+        """
+        # prefix given command with remote_exec
+        cmd = self._exec.split()
+        cmd.append(self.target_host)
+        cmd.extend(command)
+        return self.run_command(cmd, env=None)
+
+    def run_command(self, command, env=None):
+        """Run the given command with the given environment.
+        Return the output as a string.
+
+        """
+        assert isinstance(command, (list, tuple)), "list or tuple argument expected, got: %s" % command
+        self.log.debug("Remote run: %s", command)
+        try:
+            return subprocess.check_output(command, env=env)
+        except subprocess.CalledProcessError:
+            raise cdist.Error("Command failed: " + " ".join(command))
+        except OSError as error:
+            raise cdist.Error(" ".join(*args) + ": " + error.args[1])
+
+    def run_script(self, script, env=None):
+        """Run the given script with the given environment on the remote side.
+        Return the output as a string.
+
+        """
+        command = self._exec.split()
+        command.append(self.target_host)
+        command.extend(["/bin/sh", "-e"])
+        command.append(script)
+
+        self.log.debug("Remote run script: %s", command)
+        if env:
+            self.log.debug("Remote run script env: %s", env)
+        
+        try:
+            return subprocess.check_output(command, env=env)
+        except subprocess.CalledProcessError as error:
+            script_content = self.run(["cat", script])
+            self.log.error("Code that raised the error:\n%s", script_content)
+            raise RemoteScriptError(script, command, script_content)
+        except EnvironmentError as error:
+            raise cdist.Error(" ".join(command) + ": " + error.args[1])

lib/cdist/test/exec/test_remote.py

@@ -0,0 +1,111 @@
+# -*- coding: utf-8 -*-
+#
+# 2010-2011 Steven Armstrong (steven-cdist at armstrong.cc)
+#
+# 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/>.
+#
+#
+
+import unittest
+import os
+import tempfile
+import getpass
+import shutil
+import string
+import random
+
+import cdist
+from cdist.exec import remote
+
+
+class RemoteTestCase(unittest.TestCase):
+
+    def mkdtemp(self, **kwargs):
+        return tempfile.mkdtemp(prefix='tmp.cdist.test.', **kwargs)
+
+    def mkstemp(self, **kwargs):
+        return tempfile.mkstemp(prefix='tmp.cdist.test.', **kwargs)
+
+    def setUp(self):
+        self.temp_dir = self.mkdtemp()
+        target_host = 'localhost'
+        remote_base_path = self.temp_dir
+        user = getpass.getuser()
+        remote_exec = "ssh -o User=%s -q" % user
+        remote_copy = "scp -o User=%s -q" % user
+        self.remote = remote.Remote(target_host, remote_base_path, remote_exec, remote_copy)
+
+    def tearDown(self):
+        shutil.rmtree(self.temp_dir)
+
+    def test_run_success(self):
+        self.remote.run(['/bin/true'])
+
+    def test_run_fail(self):
+        self.assertRaises(cdist.Error, self.remote.run, ['/bin/false'])
+
+    def test_run_script_success(self):
+        handle, script = self.mkstemp(dir=self.temp_dir)
+        fd = open(script, "w")
+        fd.writelines(["#!/bin/sh\n", "/bin/true"])
+        fd.close()
+        self.remote.run_script(script)
+
+    def test_run_script_fail(self):
+        handle, script = self.mkstemp(dir=self.temp_dir)
+        fd = open(script, "w")
+        fd.writelines(["#!/bin/sh\n", "/bin/false"])
+        fd.close()
+        self.assertRaises(remote.RemoteScriptError, self.remote.run_script, script)
+
+    def test_run_script_get_output(self):
+        handle, script = self.mkstemp(dir=self.temp_dir)
+        fd = open(script, "w")
+        fd.writelines(["#!/bin/sh\n", "echo foobar"])
+        fd.close()
+        self.assertEqual(self.remote.run_script(script), b"foobar\n")
+
+    def test_mkdir(self):
+        temp_dir = self.mkdtemp(dir=self.temp_dir)
+        os.rmdir(temp_dir)
+        self.remote.mkdir(temp_dir)
+        self.assertTrue(os.path.isdir(temp_dir))
+
+    def test_rmdir(self):
+        temp_dir = self.mkdtemp(dir=self.temp_dir)
+        self.remote.rmdir(temp_dir)
+        self.assertFalse(os.path.isdir(temp_dir))
+
+    def test_transfer_file(self):
+        handle, source = self.mkstemp(dir=self.temp_dir)
+        target = self.mkdtemp(dir=self.temp_dir)
+        self.remote.transfer(source, target)
+        self.assertTrue(os.path.isfile(target))
+
+    def test_transfer_dir(self):
+        source = self.mkdtemp(dir=self.temp_dir)
+        # put a file in the directory as payload
+        handle, source_file = self.mkstemp(dir=source)
+        source_file_name = os.path.split(source_file)[-1]
+        target = self.mkdtemp(dir=self.temp_dir)
+        self.remote.transfer(source, target)
+        # test if the payload file is in the target directory
+        self.assertTrue(os.path.isfile(os.path.join(target, source_file_name)))
+
+    def test_create_directories(self):
+        self.remote.create_directories()
+        self.assertTrue(os.path.isdir(self.remote.base_path))
+        self.assertTrue(os.path.isdir(self.remote.conf_path))