--- /dev/null
+#
+#
+
+# Copyright (C) 2013 Google Inc.
+#
+# This program 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 2 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
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301, USA.
+
+
+"""File storage functions.
+
+"""
+
+from ganeti import errors
+from ganeti import utils
+
+DF_M_UNIT = 'M'
+DF_MIN_NUM_COLS = 4
+DF_NUM_LINES = 2
+
+
+def _ParseDfResult(dfresult):
+ """Parses the output of the call of the 'df' tool.
+
+ @type dfresult: string
+ @param dfresult: output of the 'df' call
+ @return: tuple (size, free) of the total and free disk space in MebiBytes
+ """
+ df_lines = dfresult.splitlines()
+ if len(df_lines) != DF_NUM_LINES:
+ raise errors.CommandError("'df' output has wrong number of lines: %s" %
+ len(df_lines))
+ df_values = df_lines[1].strip().split()
+ if len(df_values) < DF_MIN_NUM_COLS:
+ raise errors.CommandError("'df' output does not have enough columns: %s" %
+ len(df_values))
+ size_str = df_values[1]
+ if size_str[-1] != DF_M_UNIT:
+ raise errors.CommandError("'df': 'size' not given in Mebibytes.")
+ free_str = df_values[3]
+ if free_str[-1] != DF_M_UNIT:
+ raise errors.CommandError("'df': 'free' not given in Mebibytes.")
+ size = int(size_str[:-1])
+ free = int(free_str[:-1])
+ return (size, free)
+
+
+def GetSpaceInfo(path, _parsefn=_ParseDfResult):
+ """Retrieves the free and total space of the device where the file is
+ located.
+
+ @type path: string
+ @param path: Path of the file whose embracing device's capacity is
+ reported.
+ @type _parsefn: function
+ @param _parsefn: Function that parses the output of the 'df' command;
+ given as parameter to make this code more testable.
+ @return: a dictionary containing 'vg_size' and 'vg_free'
+ """
+ cmd = ['df', '-BM', path]
+ result = utils.RunCmd(cmd)
+ if result.failed:
+ raise errors.CommandError("Failed to run 'df' command: %s - %s" %
+ (result.fail_reason, result.output))
+ (size, free) = _parsefn(result.stdout)
+ return {"vg_size": size, "vg_free": free}
--- /dev/null
+#!/usr/bin/python
+#
+
+# Copyright (C) 2013 Google Inc.
+#
+# This program 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 2 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
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301, USA.
+
+
+"""Script for unittesting the ganeti.storage.file module"""
+
+
+import unittest
+
+from ganeti import errors
+from ganeti.storage import filestorage
+
+import testutils
+
+
+class TestFileStorageSpaceInfo(unittest.TestCase):
+
+ def testSpaceInfoPathInvalid(self):
+ """Tests that an error is raised when the given file is not existing.
+
+ """
+ self.assertRaises(errors.CommandError, filestorage.GetSpaceInfo,
+ "/path/does/not/exist/")
+
+ def testSpaceInfoPathValid(self):
+ """Tests that the 'df' command is run if the file is valid.
+
+ """
+ info = filestorage.GetSpaceInfo("/")
+
+ def testParseDfOutputValidInput(self):
+ """Tests that parsing of the output of 'df' works correctly.
+
+ """
+ valid_df_output = \
+ "Filesystem 1M-blocks Used Available Use% Mounted on\n" \
+ "/dev/mapper/sysvg-root 161002M 58421M 94403M 39% /"
+ expected_size = 161002
+ expected_free = 94403
+
+ (size, free) = filestorage._ParseDfResult(valid_df_output)
+ self.assertEqual(expected_size, size,
+ "Calculation of total size is incorrect.")
+ self.assertEqual(expected_free, free,
+ "Calculation of free space is incorrect.")
+
+
+ def testParseDfOutputInvalidInput(self):
+ """Tests that parsing of the output of 'df' works correctly when invalid
+ input is given.
+
+ """
+ invalid_output_header_missing = \
+ "/dev/mapper/sysvg-root 161002M 58421M 94403M 39% /"
+ invalid_output_dataline_missing = \
+ "Filesystem 1M-blocks Used Available Use% Mounted on\n"
+ invalid_output_wrong_num_columns = \
+ "Filesystem 1M-blocks Available\n" \
+ "/dev/mapper/sysvg-root 161002M 94403M"
+ invalid_output_units_wrong = \
+ "Filesystem 1M-blocks Used Available Use% Mounted on\n" \
+ "/dev/mapper/sysvg-root 161002G 58421G 94403G 39% /"
+ invalid_output_units_missing = \
+ "Filesystem 1M-blocks Used Available Use% Mounted on\n" \
+ "/dev/mapper/sysvg-root 161002 58421 94403 39% /"
+ invalid_outputs = [invalid_output_header_missing,
+ invalid_output_dataline_missing,
+ invalid_output_wrong_num_columns,
+ invalid_output_units_wrong,
+ invalid_output_units_missing]
+
+ for output in invalid_outputs:
+ self.assertRaises(errors.CommandError, filestorage._ParseDfResult, output)
+
+
+if __name__ == "__main__":
+ testutils.GanetiTestProgram()
projects / ganeti-local / commitdiff