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1 | 8b537bb0 | Michael Hanselmann | #
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2 | 8b537bb0 | Michael Hanselmann | #
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3 | 8b537bb0 | Michael Hanselmann | |
4 | 76b62028 | Iustin Pop | # Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Google Inc.
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5 | 8b537bb0 | Michael Hanselmann | #
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6 | 8b537bb0 | Michael Hanselmann | # This program is free software; you can redistribute it and/or modify
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7 | 8b537bb0 | Michael Hanselmann | # it under the terms of the GNU General Public License as published by
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8 | 8b537bb0 | Michael Hanselmann | # the Free Software Foundation; either version 2 of the License, or
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9 | 8b537bb0 | Michael Hanselmann | # (at your option) any later version.
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10 | 8b537bb0 | Michael Hanselmann | #
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11 | 8b537bb0 | Michael Hanselmann | # This program is distributed in the hope that it will be useful, but
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12 | 8b537bb0 | Michael Hanselmann | # WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | 8b537bb0 | Michael Hanselmann | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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14 | 8b537bb0 | Michael Hanselmann | # General Public License for more details.
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15 | 8b537bb0 | Michael Hanselmann | #
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16 | 8b537bb0 | Michael Hanselmann | # You should have received a copy of the GNU General Public License
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17 | 8b537bb0 | Michael Hanselmann | # along with this program; if not, write to the Free Software
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18 | 8b537bb0 | Michael Hanselmann | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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19 | 8b537bb0 | Michael Hanselmann | # 02110-1301, USA.
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20 | 8b537bb0 | Michael Hanselmann | |
21 | 8b537bb0 | Michael Hanselmann | |
22 | 8b537bb0 | Michael Hanselmann | """Module implementing the job queue handling."""
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23 | 8b537bb0 | Michael Hanselmann | |
24 | 8b537bb0 | Michael Hanselmann | import errno |
25 | ff699aa9 | Michael Hanselmann | import os |
26 | 8b537bb0 | Michael Hanselmann | |
27 | 8b537bb0 | Michael Hanselmann | from ganeti import constants |
28 | 8b537bb0 | Michael Hanselmann | from ganeti import errors |
29 | 82b22e19 | René Nussbaumer | from ganeti import runtime |
30 | 8b537bb0 | Michael Hanselmann | from ganeti import utils |
31 | e2b4a7ba | Michael Hanselmann | from ganeti import pathutils |
32 | 8b537bb0 | Michael Hanselmann | |
33 | 8b537bb0 | Michael Hanselmann | |
34 | 1410a389 | Michael Hanselmann | JOBS_PER_ARCHIVE_DIRECTORY = 10000
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35 | 1410a389 | Michael Hanselmann | |
36 | 1410a389 | Michael Hanselmann | |
37 | 8b537bb0 | Michael Hanselmann | def _ReadNumericFile(file_name): |
38 | 8b537bb0 | Michael Hanselmann | """Reads a file containing a number.
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39 | 8b537bb0 | Michael Hanselmann |
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40 | 8b537bb0 | Michael Hanselmann | @rtype: None or int
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41 | 8b537bb0 | Michael Hanselmann | @return: None if file is not found, otherwise number
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42 | 8b537bb0 | Michael Hanselmann |
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43 | 8b537bb0 | Michael Hanselmann | """
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44 | 8b537bb0 | Michael Hanselmann | try:
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45 | 4fdedd09 | Michael Hanselmann | contents = utils.ReadFile(file_name) |
46 | 6358dbc2 | Guido Trotter | except EnvironmentError, err: |
47 | 8b537bb0 | Michael Hanselmann | if err.errno in (errno.ENOENT, ): |
48 | 8b537bb0 | Michael Hanselmann | return None |
49 | 8b537bb0 | Michael Hanselmann | raise
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50 | 8b537bb0 | Michael Hanselmann | |
51 | 4fdedd09 | Michael Hanselmann | try:
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52 | 4fdedd09 | Michael Hanselmann | return int(contents) |
53 | 4fdedd09 | Michael Hanselmann | except (ValueError, TypeError), err: |
54 | 4fdedd09 | Michael Hanselmann | # Couldn't convert to int
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55 | 4fdedd09 | Michael Hanselmann | raise errors.JobQueueError("Content of file '%s' is not numeric: %s" % |
56 | 4fdedd09 | Michael Hanselmann | (file_name, err)) |
57 | 4fdedd09 | Michael Hanselmann | |
58 | 8b537bb0 | Michael Hanselmann | |
59 | 8b537bb0 | Michael Hanselmann | def ReadSerial(): |
60 | 8b537bb0 | Michael Hanselmann | """Read the serial file.
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61 | 8b537bb0 | Michael Hanselmann |
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62 | 8b537bb0 | Michael Hanselmann | The queue should be locked while this function is called.
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63 | 8b537bb0 | Michael Hanselmann |
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64 | 8b537bb0 | Michael Hanselmann | """
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65 | e2b4a7ba | Michael Hanselmann | return _ReadNumericFile(pathutils.JOB_QUEUE_SERIAL_FILE)
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66 | 8b537bb0 | Michael Hanselmann | |
67 | 8b537bb0 | Michael Hanselmann | |
68 | 8b537bb0 | Michael Hanselmann | def ReadVersion(): |
69 | 8b537bb0 | Michael Hanselmann | """Read the queue version.
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70 | 8b537bb0 | Michael Hanselmann |
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71 | 8b537bb0 | Michael Hanselmann | The queue should be locked while this function is called.
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72 | 8b537bb0 | Michael Hanselmann |
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73 | 8b537bb0 | Michael Hanselmann | """
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74 | e2b4a7ba | Michael Hanselmann | return _ReadNumericFile(pathutils.JOB_QUEUE_VERSION_FILE)
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75 | 8b537bb0 | Michael Hanselmann | |
76 | 8b537bb0 | Michael Hanselmann | |
77 | 5d6fb8eb | Michael Hanselmann | def InitAndVerifyQueue(must_lock): |
78 | 8b537bb0 | Michael Hanselmann | """Open and lock job queue.
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79 | 8b537bb0 | Michael Hanselmann |
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80 | 8b537bb0 | Michael Hanselmann | If necessary, the queue is automatically initialized.
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81 | 8b537bb0 | Michael Hanselmann |
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82 | 5d6fb8eb | Michael Hanselmann | @type must_lock: bool
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83 | 5d6fb8eb | Michael Hanselmann | @param must_lock: Whether an exclusive lock must be held.
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84 | 8b537bb0 | Michael Hanselmann | @rtype: utils.FileLock
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85 | 8b537bb0 | Michael Hanselmann | @return: Lock object for the queue. This can be used to change the
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86 | 8b537bb0 | Michael Hanselmann | locking mode.
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87 | 8b537bb0 | Michael Hanselmann |
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88 | 8b537bb0 | Michael Hanselmann | """
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89 | 82b22e19 | René Nussbaumer | getents = runtime.GetEnts() |
90 | 8b537bb0 | Michael Hanselmann | |
91 | 8b537bb0 | Michael Hanselmann | # Lock queue
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92 | e2b4a7ba | Michael Hanselmann | queue_lock = utils.FileLock.Open(pathutils.JOB_QUEUE_LOCK_FILE) |
93 | 8b537bb0 | Michael Hanselmann | try:
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94 | 5d6fb8eb | Michael Hanselmann | # The queue needs to be locked in exclusive mode to write to the serial and
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95 | 5d6fb8eb | Michael Hanselmann | # version files.
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96 | 5d6fb8eb | Michael Hanselmann | if must_lock:
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97 | 5d6fb8eb | Michael Hanselmann | queue_lock.Exclusive(blocking=True)
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98 | 5d6fb8eb | Michael Hanselmann | holding_lock = True
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99 | 8b537bb0 | Michael Hanselmann | else:
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100 | 5d6fb8eb | Michael Hanselmann | try:
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101 | 5d6fb8eb | Michael Hanselmann | queue_lock.Exclusive(blocking=False)
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102 | 5d6fb8eb | Michael Hanselmann | holding_lock = True
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103 | 5d6fb8eb | Michael Hanselmann | except errors.LockError:
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104 | 5d6fb8eb | Michael Hanselmann | # Ignore errors and assume the process keeping the lock checked
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105 | 5d6fb8eb | Michael Hanselmann | # everything.
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106 | 5d6fb8eb | Michael Hanselmann | holding_lock = False
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107 | 5d6fb8eb | Michael Hanselmann | |
108 | 5d6fb8eb | Michael Hanselmann | if holding_lock:
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109 | 5d6fb8eb | Michael Hanselmann | # Verify version
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110 | 8b537bb0 | Michael Hanselmann | version = ReadVersion() |
111 | 5d6fb8eb | Michael Hanselmann | if version is None: |
112 | 5d6fb8eb | Michael Hanselmann | # Write new version file
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113 | e2b4a7ba | Michael Hanselmann | utils.WriteFile(pathutils.JOB_QUEUE_VERSION_FILE, |
114 | fe05a931 | Michele Tartara | uid=getents.masterd_uid, gid=getents.daemons_gid, |
115 | fe05a931 | Michele Tartara | mode=constants.JOB_QUEUE_FILES_PERMS, |
116 | 5d6fb8eb | Michael Hanselmann | data="%s\n" % constants.JOB_QUEUE_VERSION)
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117 | 8b537bb0 | Michael Hanselmann | |
118 | 5d6fb8eb | Michael Hanselmann | # Read again
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119 | 5d6fb8eb | Michael Hanselmann | version = ReadVersion() |
120 | 8b537bb0 | Michael Hanselmann | |
121 | 5d6fb8eb | Michael Hanselmann | if version != constants.JOB_QUEUE_VERSION:
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122 | 5d6fb8eb | Michael Hanselmann | raise errors.JobQueueError("Found job queue version %s, expected %s", |
123 | 5d6fb8eb | Michael Hanselmann | version, constants.JOB_QUEUE_VERSION) |
124 | 8b537bb0 | Michael Hanselmann | |
125 | 8b537bb0 | Michael Hanselmann | serial = ReadSerial() |
126 | 5d6fb8eb | Michael Hanselmann | if serial is None: |
127 | 5d6fb8eb | Michael Hanselmann | # Write new serial file
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128 | e2b4a7ba | Michael Hanselmann | utils.WriteFile(pathutils.JOB_QUEUE_SERIAL_FILE, |
129 | fe05a931 | Michele Tartara | uid=getents.masterd_uid, gid=getents.daemons_gid, |
130 | fe05a931 | Michele Tartara | mode=constants.JOB_QUEUE_FILES_PERMS, |
131 | 5d6fb8eb | Michael Hanselmann | data="%s\n" % 0) |
132 | 5d6fb8eb | Michael Hanselmann | |
133 | 5d6fb8eb | Michael Hanselmann | # Read again
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134 | 5d6fb8eb | Michael Hanselmann | serial = ReadSerial() |
135 | 8b537bb0 | Michael Hanselmann | |
136 | 5d6fb8eb | Michael Hanselmann | if serial is None: |
137 | 5d6fb8eb | Michael Hanselmann | # There must be a serious problem
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138 | fe267188 | Iustin Pop | raise errors.JobQueueError("Can't read/parse the job queue" |
139 | fe267188 | Iustin Pop | " serial file")
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140 | 8b537bb0 | Michael Hanselmann | |
141 | f56377a3 | Michael Hanselmann | if not must_lock: |
142 | fe267188 | Iustin Pop | # There's no need for more error handling. Closing the lock
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143 | fe267188 | Iustin Pop | # file below in case of an error will unlock it anyway.
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144 | f56377a3 | Michael Hanselmann | queue_lock.Unlock() |
145 | f56377a3 | Michael Hanselmann | |
146 | 8b537bb0 | Michael Hanselmann | except:
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147 | 8b537bb0 | Michael Hanselmann | queue_lock.Close() |
148 | 8b537bb0 | Michael Hanselmann | raise
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149 | 8b537bb0 | Michael Hanselmann | |
150 | 8b537bb0 | Michael Hanselmann | return queue_lock
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151 | ff699aa9 | Michael Hanselmann | |
152 | ff699aa9 | Michael Hanselmann | |
153 | ff699aa9 | Michael Hanselmann | def CheckDrainFlag(): |
154 | ff699aa9 | Michael Hanselmann | """Check if the queue is marked to be drained.
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155 | ff699aa9 | Michael Hanselmann |
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156 | ff699aa9 | Michael Hanselmann | This currently uses the queue drain file, which makes it a per-node flag.
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157 | ff699aa9 | Michael Hanselmann | In the future this can be moved to the config file.
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158 | ff699aa9 | Michael Hanselmann |
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159 | ff699aa9 | Michael Hanselmann | @rtype: boolean
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160 | ff699aa9 | Michael Hanselmann | @return: True if the job queue is marked drained
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161 | ff699aa9 | Michael Hanselmann |
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162 | ff699aa9 | Michael Hanselmann | """
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163 | e2b4a7ba | Michael Hanselmann | return os.path.exists(pathutils.JOB_QUEUE_DRAIN_FILE)
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164 | ff699aa9 | Michael Hanselmann | |
165 | ff699aa9 | Michael Hanselmann | |
166 | ff699aa9 | Michael Hanselmann | def SetDrainFlag(drain_flag): |
167 | ff699aa9 | Michael Hanselmann | """Sets the drain flag for the queue.
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168 | ff699aa9 | Michael Hanselmann |
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169 | ff699aa9 | Michael Hanselmann | @type drain_flag: boolean
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170 | ff699aa9 | Michael Hanselmann | @param drain_flag: Whether to set or unset the drain flag
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171 | ff699aa9 | Michael Hanselmann | @attention: This function should only called the current holder of the queue
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172 | ff699aa9 | Michael Hanselmann | lock
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173 | ff699aa9 | Michael Hanselmann |
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174 | ff699aa9 | Michael Hanselmann | """
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175 | ff699aa9 | Michael Hanselmann | getents = runtime.GetEnts() |
176 | ff699aa9 | Michael Hanselmann | |
177 | ff699aa9 | Michael Hanselmann | if drain_flag:
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178 | e2b4a7ba | Michael Hanselmann | utils.WriteFile(pathutils.JOB_QUEUE_DRAIN_FILE, data="",
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179 | fe05a931 | Michele Tartara | uid=getents.masterd_uid, gid=getents.daemons_gid, |
180 | fe05a931 | Michele Tartara | mode=constants.JOB_QUEUE_FILES_PERMS) |
181 | ff699aa9 | Michael Hanselmann | else:
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182 | e2b4a7ba | Michael Hanselmann | utils.RemoveFile(pathutils.JOB_QUEUE_DRAIN_FILE) |
183 | ff699aa9 | Michael Hanselmann | |
184 | ff699aa9 | Michael Hanselmann | assert (not drain_flag) ^ CheckDrainFlag() |
185 | 1410a389 | Michael Hanselmann | |
186 | 1410a389 | Michael Hanselmann | |
187 | 1410a389 | Michael Hanselmann | def FormatJobID(job_id): |
188 | 76b62028 | Iustin Pop | """Convert a job ID to int format.
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189 | 1410a389 | Michael Hanselmann |
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190 | 76b62028 | Iustin Pop | Currently this just is a no-op that performs some checks, but if we
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191 | 76b62028 | Iustin Pop | want to change the job id format this will abstract this change.
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192 | 1410a389 | Michael Hanselmann |
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193 | 1410a389 | Michael Hanselmann | @type job_id: int or long
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194 | 1410a389 | Michael Hanselmann | @param job_id: the numeric job id
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195 | 76b62028 | Iustin Pop | @rtype: int
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196 | 1410a389 | Michael Hanselmann | @return: the formatted job id
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197 | 1410a389 | Michael Hanselmann |
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198 | 1410a389 | Michael Hanselmann | """
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199 | 1410a389 | Michael Hanselmann | if not isinstance(job_id, (int, long)): |
200 | 1410a389 | Michael Hanselmann | raise errors.ProgrammerError("Job ID '%s' not numeric" % job_id) |
201 | 1410a389 | Michael Hanselmann | if job_id < 0: |
202 | 1410a389 | Michael Hanselmann | raise errors.ProgrammerError("Job ID %s is negative" % job_id) |
203 | 1410a389 | Michael Hanselmann | |
204 | 76b62028 | Iustin Pop | return job_id
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205 | 1410a389 | Michael Hanselmann | |
206 | 1410a389 | Michael Hanselmann | |
207 | 1410a389 | Michael Hanselmann | def GetArchiveDirectory(job_id): |
208 | 1410a389 | Michael Hanselmann | """Returns the archive directory for a job.
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209 | 1410a389 | Michael Hanselmann |
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210 | 1410a389 | Michael Hanselmann | @type job_id: str
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211 | 1410a389 | Michael Hanselmann | @param job_id: Job identifier
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212 | 1410a389 | Michael Hanselmann | @rtype: str
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213 | 1410a389 | Michael Hanselmann | @return: Directory name
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214 | 1410a389 | Michael Hanselmann |
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215 | 1410a389 | Michael Hanselmann | """
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216 | 526f866b | Michael Hanselmann | return str(ParseJobId(job_id) / JOBS_PER_ARCHIVE_DIRECTORY) |
217 | 526f866b | Michael Hanselmann | |
218 | 526f866b | Michael Hanselmann | |
219 | 526f866b | Michael Hanselmann | def ParseJobId(job_id): |
220 | 526f866b | Michael Hanselmann | """Parses a job ID and converts it to integer.
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221 | 526f866b | Michael Hanselmann |
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222 | 526f866b | Michael Hanselmann | """
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223 | 526f866b | Michael Hanselmann | try:
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224 | 526f866b | Michael Hanselmann | return int(job_id) |
225 | 526f866b | Michael Hanselmann | except (ValueError, TypeError): |
226 | 526f866b | Michael Hanselmann | raise errors.ParameterError("Invalid job ID '%s'" % job_id) |