root / snf-cyclades-app / synnefo / plankton / backend.py @ 0efb43cd
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1 | cda71050 | Christos Stavrakakis | # Copyright 2011-2013 GRNET S.A. All rights reserved.
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2 | cda71050 | Christos Stavrakakis | |
3 | c34de90f | Giorgos Verigakis | #
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4 | c34de90f | Giorgos Verigakis | # Redistribution and use in source and binary forms, with or
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5 | c34de90f | Giorgos Verigakis | # without modification, are permitted provided that the following
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6 | c34de90f | Giorgos Verigakis | # conditions are met:
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7 | c34de90f | Giorgos Verigakis | #
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8 | c34de90f | Giorgos Verigakis | # 1. Redistributions of source code must retain the above
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9 | c34de90f | Giorgos Verigakis | # copyright notice, this list of conditions and the following
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10 | c34de90f | Giorgos Verigakis | # disclaimer.
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11 | c34de90f | Giorgos Verigakis | #
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12 | c34de90f | Giorgos Verigakis | # 2. Redistributions in binary form must reproduce the above
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13 | c34de90f | Giorgos Verigakis | # copyright notice, this list of conditions and the following
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14 | c34de90f | Giorgos Verigakis | # disclaimer in the documentation and/or other materials
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15 | c34de90f | Giorgos Verigakis | # provided with the distribution.
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16 | c34de90f | Giorgos Verigakis | #
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17 | c34de90f | Giorgos Verigakis | # THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
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18 | c34de90f | Giorgos Verigakis | # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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19 | c34de90f | Giorgos Verigakis | # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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20 | c34de90f | Giorgos Verigakis | # PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
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21 | c34de90f | Giorgos Verigakis | # CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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22 | c34de90f | Giorgos Verigakis | # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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23 | c34de90f | Giorgos Verigakis | # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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24 | c34de90f | Giorgos Verigakis | # USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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25 | c34de90f | Giorgos Verigakis | # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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26 | c34de90f | Giorgos Verigakis | # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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27 | c34de90f | Giorgos Verigakis | # ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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28 | c34de90f | Giorgos Verigakis | # POSSIBILITY OF SUCH DAMAGE.
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29 | c34de90f | Giorgos Verigakis | #
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30 | c34de90f | Giorgos Verigakis | # The views and conclusions contained in the software and
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31 | c34de90f | Giorgos Verigakis | # documentation are those of the authors and should not be
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32 | c34de90f | Giorgos Verigakis | # interpreted as representing official policies, either expressed
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33 | c34de90f | Giorgos Verigakis | # or implied, of GRNET S.A.
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34 | c34de90f | Giorgos Verigakis | |
35 | f5afd99b | Giorgos Verigakis | """
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36 | bfd9f988 | Giorgos Verigakis | The Plankton attributes are the following:
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37 | 0a72907b | Giorgos Verigakis | - checksum: the 'hash' meta
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38 | 7bd1d3b5 | Giorgos Verigakis | - container_format: stored as a user meta
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39 | 0a72907b | Giorgos Verigakis | - created_at: the 'modified' meta of the first version
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40 | 0a72907b | Giorgos Verigakis | - deleted_at: the timestamp of the last version
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41 | 7bd1d3b5 | Giorgos Verigakis | - disk_format: stored as a user meta
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42 | 0a72907b | Giorgos Verigakis | - id: the 'uuid' meta
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43 | f5afd99b | Giorgos Verigakis | - is_public: True if there is a * entry for the read permission
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44 | 0a72907b | Giorgos Verigakis | - location: generated based on the file's path
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45 | 7bd1d3b5 | Giorgos Verigakis | - name: stored as a user meta
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46 | 0a72907b | Giorgos Verigakis | - owner: the file's account
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47 | 7bd1d3b5 | Giorgos Verigakis | - properties: stored as user meta prefixed with PROPERTY_PREFIX
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48 | 0a72907b | Giorgos Verigakis | - size: the 'bytes' meta
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49 | 7bd1d3b5 | Giorgos Verigakis | - status: stored as a system meta
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50 | 7bd1d3b5 | Giorgos Verigakis | - store: is always 'pithos'
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51 | 0a72907b | Giorgos Verigakis | - updated_at: the 'modified' meta
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52 | f5afd99b | Giorgos Verigakis | """
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53 | f5afd99b | Giorgos Verigakis | |
54 | c34de90f | Giorgos Verigakis | import json |
55 | c23d211a | Giorgos Verigakis | import warnings |
56 | cda71050 | Christos Stavrakakis | import logging |
57 | 9393d4ee | Kostas Papadimitriou | import os |
58 | 9393d4ee | Kostas Papadimitriou | |
59 | 3a528c36 | Christos Stavrakakis | from time import time, gmtime, strftime |
60 | cda71050 | Christos Stavrakakis | from functools import wraps |
61 | cda71050 | Christos Stavrakakis | from operator import itemgetter |
62 | c34de90f | Giorgos Verigakis | |
63 | cda71050 | Christos Stavrakakis | from django.conf import settings |
64 | 9393d4ee | Kostas Papadimitriou | from django.utils import importlib |
65 | cda71050 | Christos Stavrakakis | from pithos.backends.base import NotAllowedError, VersionNotExists |
66 | f4366b6c | Stratos Psomadakis | |
67 | 469d0997 | Georgios D. Tsoukalas | logger = logging.getLogger(__name__) |
68 | c34de90f | Giorgos Verigakis | |
69 | c34de90f | Giorgos Verigakis | |
70 | 0a72907b | Giorgos Verigakis | PLANKTON_DOMAIN = 'plankton'
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71 | bfd9f988 | Giorgos Verigakis | PLANKTON_PREFIX = 'plankton:'
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72 | 7bd1d3b5 | Giorgos Verigakis | PROPERTY_PREFIX = 'property:'
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73 | 7bd1d3b5 | Giorgos Verigakis | |
74 | d58ea30a | Christos Stavrakakis | PLANKTON_META = ('container_format', 'disk_format', 'name', |
75 | 3a528c36 | Christos Stavrakakis | 'status', 'created_at') |
76 | c34de90f | Giorgos Verigakis | |
77 | 0efb43cd | Christos Stavrakakis | MAX_META_KEY_LENGTH = 128 - len(PLANKTON_DOMAIN) - len(PROPERTY_PREFIX) |
78 | 0efb43cd | Christos Stavrakakis | MAX_META_VALUE_LENGTH = 256
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79 | 0efb43cd | Christos Stavrakakis | |
80 | 7784ab88 | Christos Stavrakakis | from pithos.backends.util import PithosBackendPool |
81 | 7784ab88 | Christos Stavrakakis | _pithos_backend_pool = \ |
82 | b336e6fa | Georgios D. Tsoukalas | PithosBackendPool( |
83 | e3f006b0 | Christos Stavrakakis | settings.PITHOS_BACKEND_POOL_SIZE, |
84 | e407f159 | Ilias Tsitsimpis | astakos_auth_url=settings.ASTAKOS_AUTH_URL, |
85 | 18c4414d | Giorgos Korfiatis | service_token=settings.CYCLADES_SERVICE_TOKEN, |
86 | b0c95903 | Giorgos Korfiatis | astakosclient_poolsize=settings.CYCLADES_ASTAKOSCLIENT_POOLSIZE, |
87 | b336e6fa | Georgios D. Tsoukalas | db_connection=settings.BACKEND_DB_CONNECTION, |
88 | b336e6fa | Georgios D. Tsoukalas | block_path=settings.BACKEND_BLOCK_PATH) |
89 | 7784ab88 | Christos Stavrakakis | |
90 | 7784ab88 | Christos Stavrakakis | |
91 | 7784ab88 | Christos Stavrakakis | def get_pithos_backend(): |
92 | 7784ab88 | Christos Stavrakakis | return _pithos_backend_pool.pool_get()
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93 | 7784ab88 | Christos Stavrakakis | |
94 | 7784ab88 | Christos Stavrakakis | |
95 | cda71050 | Christos Stavrakakis | def create_url(account, container, name): |
96 | cda71050 | Christos Stavrakakis | assert "/" not in account, "Invalid account" |
97 | cda71050 | Christos Stavrakakis | assert "/" not in container, "Invalid container" |
98 | cda71050 | Christos Stavrakakis | return "pithos://%s/%s/%s" % (account, container, name) |
99 | cda71050 | Christos Stavrakakis | |
100 | cda71050 | Christos Stavrakakis | |
101 | cda71050 | Christos Stavrakakis | def split_url(url): |
102 | cda71050 | Christos Stavrakakis | """Returns (accout, container, object) from a url string"""
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103 | cda71050 | Christos Stavrakakis | t = url.split('/', 4) |
104 | 59573532 | Christos Stavrakakis | assert t[0] == "pithos:", "Invalid url" |
105 | cda71050 | Christos Stavrakakis | assert len(t) == 5, "Invalid url" |
106 | cda71050 | Christos Stavrakakis | return t[2:5] |
107 | cda71050 | Christos Stavrakakis | |
108 | cda71050 | Christos Stavrakakis | |
109 | cda71050 | Christos Stavrakakis | def format_timestamp(t): |
110 | cda71050 | Christos Stavrakakis | return strftime('%Y-%m-%d %H:%M:%S', gmtime(t)) |
111 | cda71050 | Christos Stavrakakis | |
112 | cda71050 | Christos Stavrakakis | |
113 | 2db7d9df | Christos Stavrakakis | def handle_backend_exceptions(func): |
114 | 2db7d9df | Christos Stavrakakis | @wraps(func)
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115 | 2db7d9df | Christos Stavrakakis | def wrapper(*args, **kwargs): |
116 | 2db7d9df | Christos Stavrakakis | try:
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117 | 2db7d9df | Christos Stavrakakis | return func(*args, **kwargs)
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118 | f6ff4b40 | Christos Stavrakakis | except NotAllowedError:
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119 | cda71050 | Christos Stavrakakis | raise Forbidden
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120 | cda71050 | Christos Stavrakakis | except NameError: |
121 | cda71050 | Christos Stavrakakis | raise ImageNotFound
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122 | cda71050 | Christos Stavrakakis | except VersionNotExists:
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123 | cda71050 | Christos Stavrakakis | raise ImageNotFound
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124 | 2db7d9df | Christos Stavrakakis | return wrapper
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125 | 2db7d9df | Christos Stavrakakis | |
126 | 2db7d9df | Christos Stavrakakis | |
127 | 3347a30c | Georgios D. Tsoukalas | def commit_on_success(func): |
128 | 3347a30c | Georgios D. Tsoukalas | def wrapper(self, *args, **kwargs): |
129 | 3347a30c | Georgios D. Tsoukalas | backend = self.backend
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130 | 3347a30c | Georgios D. Tsoukalas | backend.pre_exec() |
131 | 3347a30c | Georgios D. Tsoukalas | try:
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132 | 3347a30c | Georgios D. Tsoukalas | ret = func(self, *args, **kwargs)
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133 | 3347a30c | Georgios D. Tsoukalas | except:
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134 | 3347a30c | Georgios D. Tsoukalas | backend.post_exec(False)
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135 | 3347a30c | Georgios D. Tsoukalas | raise
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136 | 3347a30c | Georgios D. Tsoukalas | else:
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137 | 3347a30c | Georgios D. Tsoukalas | backend.post_exec(True)
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138 | 3347a30c | Georgios D. Tsoukalas | return ret
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139 | 3347a30c | Georgios D. Tsoukalas | return wrapper
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140 | 3347a30c | Georgios D. Tsoukalas | |
141 | 3347a30c | Georgios D. Tsoukalas | |
142 | ffab341c | Christos Stavrakakis | class ImageBackend(object): |
143 | f5afd99b | Giorgos Verigakis | """A wrapper arround the pithos backend to simplify image handling."""
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144 | 1e28ba40 | Christos Stavrakakis | |
145 | c34de90f | Giorgos Verigakis | def __init__(self, user): |
146 | c34de90f | Giorgos Verigakis | self.user = user
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147 | 7784ab88 | Christos Stavrakakis | |
148 | c23d211a | Giorgos Verigakis | original_filters = warnings.filters |
149 | c23d211a | Giorgos Verigakis | warnings.simplefilter('ignore') # Suppress SQLAlchemy warnings |
150 | 7784ab88 | Christos Stavrakakis | self.backend = get_pithos_backend()
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151 | c23d211a | Giorgos Verigakis | warnings.filters = original_filters # Restore warnings
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152 | 7784ab88 | Christos Stavrakakis | |
153 | cda71050 | Christos Stavrakakis | def close(self): |
154 | cda71050 | Christos Stavrakakis | """Close PithosBackend(return to pool)"""
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155 | cda71050 | Christos Stavrakakis | self.backend.close()
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156 | cda71050 | Christos Stavrakakis | |
157 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
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158 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
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159 | cda71050 | Christos Stavrakakis | def get_image(self, image_uuid): |
160 | cda71050 | Christos Stavrakakis | """Retrieve information about an image."""
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161 | cda71050 | Christos Stavrakakis | image_url = self._get_image_url(image_uuid)
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162 | cda71050 | Christos Stavrakakis | return self._get_image(image_url) |
163 | 1e28ba40 | Christos Stavrakakis | |
164 | cda71050 | Christos Stavrakakis | def _get_image_url(self, image_uuid): |
165 | cda71050 | Christos Stavrakakis | """Get the Pithos url that corresponds to an image UUID."""
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166 | cda71050 | Christos Stavrakakis | account, container, name = self.backend.get_uuid(self.user, image_uuid) |
167 | cda71050 | Christos Stavrakakis | return create_url(account, container, name)
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168 | 1e28ba40 | Christos Stavrakakis | |
169 | cda71050 | Christos Stavrakakis | def _get_image(self, image_url): |
170 | cda71050 | Christos Stavrakakis | """Get information about an Image.
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171 | cda71050 | Christos Stavrakakis |
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172 | cda71050 | Christos Stavrakakis | Get all available information about an Image.
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173 | cda71050 | Christos Stavrakakis | """
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174 | cda71050 | Christos Stavrakakis | account, container, name = split_url(image_url) |
175 | cda71050 | Christos Stavrakakis | try:
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176 | cda71050 | Christos Stavrakakis | meta = self._get_meta(image_url)
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177 | 14c94c48 | Christos Stavrakakis | meta["deleted"] = "" |
178 | cda71050 | Christos Stavrakakis | except NameError: |
179 | 3a528c36 | Christos Stavrakakis | versions = self.backend.list_versions(self.user, account, |
180 | 3a528c36 | Christos Stavrakakis | container, name) |
181 | 3a528c36 | Christos Stavrakakis | if not versions: |
182 | 3a528c36 | Christos Stavrakakis | raise Exception("Image without versions %s" % image_url) |
183 | 7bd1d3b5 | Giorgos Verigakis | # Object was deleted, use the latest version
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184 | 7bd1d3b5 | Giorgos Verigakis | version, timestamp = versions[-1]
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185 | cda71050 | Christos Stavrakakis | meta = self._get_meta(image_url, version)
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186 | 14c94c48 | Christos Stavrakakis | meta["deleted"] = timestamp
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187 | 14c94c48 | Christos Stavrakakis | |
188 | 72224dd6 | Christos Stavrakakis | # XXX: Check that an object is a plankton image! PithosBackend will
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189 | 72224dd6 | Christos Stavrakakis | # return common metadata for an object, even if it has no metadata in
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190 | 72224dd6 | Christos Stavrakakis | # plankton domain. All images must have a name, so we check if a file
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191 | 72224dd6 | Christos Stavrakakis | # is an image by checking if they are having an image name.
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192 | 0a72907b | Giorgos Verigakis | if PLANKTON_PREFIX + 'name' not in meta: |
193 | 72224dd6 | Christos Stavrakakis | raise ImageNotFound
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194 | 1e28ba40 | Christos Stavrakakis | |
195 | cda71050 | Christos Stavrakakis | permissions = self._get_permissions(image_url)
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196 | 14c94c48 | Christos Stavrakakis | return image_to_dict(image_url, meta, permissions)
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197 | 1e28ba40 | Christos Stavrakakis | |
198 | cda71050 | Christos Stavrakakis | def _get_meta(self, image_url, version=None): |
199 | cda71050 | Christos Stavrakakis | """Get object's metadata."""
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200 | cda71050 | Christos Stavrakakis | account, container, name = split_url(image_url) |
201 | cda71050 | Christos Stavrakakis | return self.backend.get_object_meta(self.user, account, container, |
202 | cda71050 | Christos Stavrakakis | name, PLANKTON_DOMAIN, version) |
203 | 1e28ba40 | Christos Stavrakakis | |
204 | cda71050 | Christos Stavrakakis | def _update_meta(self, image_url, meta, replace=False): |
205 | cda71050 | Christos Stavrakakis | """Update object's metadata."""
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206 | cda71050 | Christos Stavrakakis | account, container, name = split_url(image_url) |
207 | 1e28ba40 | Christos Stavrakakis | |
208 | d58ea30a | Christos Stavrakakis | prefixed = [(PLANKTON_PREFIX + k, v) for k, v in meta.items() |
209 | d58ea30a | Christos Stavrakakis | if k in PLANKTON_META or k.startswith(PROPERTY_PREFIX)] |
210 | d58ea30a | Christos Stavrakakis | prefixed = dict(prefixed)
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211 | 1e28ba40 | Christos Stavrakakis | |
212 | 0efb43cd | Christos Stavrakakis | for k, v in prefixed.items(): |
213 | 0efb43cd | Christos Stavrakakis | if len(k) > 128: |
214 | 0efb43cd | Christos Stavrakakis | raise InvalidMetadata('Metadata keys should be less than %s ' |
215 | 0efb43cd | Christos Stavrakakis | 'characters' % MAX_META_KEY_LENGTH)
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216 | 0efb43cd | Christos Stavrakakis | if len(v) > 256: |
217 | 0efb43cd | Christos Stavrakakis | raise InvalidMetadata('Metadata values should be less than %s ' |
218 | 0efb43cd | Christos Stavrakakis | 'characters.' % MAX_META_VALUE_LENGTH)
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219 | 0efb43cd | Christos Stavrakakis | |
220 | cda71050 | Christos Stavrakakis | self.backend.update_object_meta(self.user, account, container, name, |
221 | cda71050 | Christos Stavrakakis | PLANKTON_DOMAIN, prefixed, replace) |
222 | 62d3ea53 | Christos Stavrakakis | logger.debug("User '%s' updated image '%s', meta: '%s'", self.user, |
223 | 62d3ea53 | Christos Stavrakakis | image_url, prefixed) |
224 | 1e28ba40 | Christos Stavrakakis | |
225 | cda71050 | Christos Stavrakakis | def _get_permissions(self, image_url): |
226 | cda71050 | Christos Stavrakakis | """Get object's permissions."""
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227 | cda71050 | Christos Stavrakakis | account, container, name = split_url(image_url) |
228 | cda71050 | Christos Stavrakakis | _a, path, permissions = \ |
229 | cda71050 | Christos Stavrakakis | self.backend.get_object_permissions(self.user, account, container, |
230 | cda71050 | Christos Stavrakakis | name) |
231 | 1e28ba40 | Christos Stavrakakis | |
232 | 69cdf66c | Nanakos Chrysostomos | if path is None and permissions != {}: |
233 | 69cdf66c | Nanakos Chrysostomos | logger.warning("Image '%s' got permissions '%s' from 'None' path.",
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234 | 69cdf66c | Nanakos Chrysostomos | image_url, permissions) |
235 | 69cdf66c | Nanakos Chrysostomos | raise Exception("Database Inconsistency Error:" |
236 | 69cdf66c | Nanakos Chrysostomos | " Image '%s' got permissions from 'None' path." %
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237 | 69cdf66c | Nanakos Chrysostomos | image_url) |
238 | 1e28ba40 | Christos Stavrakakis | |
239 | cda71050 | Christos Stavrakakis | return permissions
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240 | 1e28ba40 | Christos Stavrakakis | |
241 | cda71050 | Christos Stavrakakis | def _update_permissions(self, image_url, permissions): |
242 | cda71050 | Christos Stavrakakis | """Update object's permissions."""
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243 | cda71050 | Christos Stavrakakis | account, container, name = split_url(image_url) |
244 | cda71050 | Christos Stavrakakis | self.backend.update_object_permissions(self.user, account, container, |
245 | cda71050 | Christos Stavrakakis | name, permissions) |
246 | 62d3ea53 | Christos Stavrakakis | logger.debug("User '%s' updated image '%s', permissions: '%s'",
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247 | 62d3ea53 | Christos Stavrakakis | self.user, image_url, permissions)
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248 | 1e28ba40 | Christos Stavrakakis | |
249 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
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250 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
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251 | cda71050 | Christos Stavrakakis | def unregister(self, image_uuid): |
252 | cda71050 | Christos Stavrakakis | """Unregister an image.
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253 | 1e28ba40 | Christos Stavrakakis |
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254 | cda71050 | Christos Stavrakakis | Unregister an image, by removing all metadata from the Pithos
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255 | cda71050 | Christos Stavrakakis | file that exist in the PLANKTON_DOMAIN.
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256 | 1e28ba40 | Christos Stavrakakis |
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257 | cda71050 | Christos Stavrakakis | """
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258 | cda71050 | Christos Stavrakakis | image_url = self._get_image_url(image_uuid)
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259 | cda71050 | Christos Stavrakakis | self._get_image(image_url) # Assert that it is an image |
260 | cda71050 | Christos Stavrakakis | # Unregister the image by removing all metadata from domain
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261 | cda71050 | Christos Stavrakakis | # 'PLANKTON_DOMAIN'
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262 | 22b5ac0b | Christos Stavrakakis | meta = {} |
263 | 22b5ac0b | Christos Stavrakakis | self._update_meta(image_url, meta, True) |
264 | 62d3ea53 | Christos Stavrakakis | logger.debug("User '%s' deleted image '%s'", self.user, image_url) |
265 | 1e28ba40 | Christos Stavrakakis | |
266 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
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267 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
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268 | cda71050 | Christos Stavrakakis | def add_user(self, image_uuid, add_user): |
269 | cda71050 | Christos Stavrakakis | """Add a user as an image member.
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270 | cda71050 | Christos Stavrakakis |
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271 | cda71050 | Christos Stavrakakis | Update read permissions of Pithos file, to include the specified user.
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272 | cda71050 | Christos Stavrakakis |
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273 | cda71050 | Christos Stavrakakis | """
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274 | cda71050 | Christos Stavrakakis | image_url = self._get_image_url(image_uuid)
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275 | cda71050 | Christos Stavrakakis | self._get_image(image_url) # Assert that it is an image |
276 | cda71050 | Christos Stavrakakis | permissions = self._get_permissions(image_url)
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277 | cda71050 | Christos Stavrakakis | read = set(permissions.get("read", [])) |
278 | cda71050 | Christos Stavrakakis | assert(isinstance(add_user, (str, unicode))) |
279 | cda71050 | Christos Stavrakakis | read.add(add_user) |
280 | cda71050 | Christos Stavrakakis | permissions["read"] = list(read) |
281 | cda71050 | Christos Stavrakakis | self._update_permissions(image_url, permissions)
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282 | 1e28ba40 | Christos Stavrakakis | |
283 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
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284 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
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285 | cda71050 | Christos Stavrakakis | def remove_user(self, image_uuid, remove_user): |
286 | cda71050 | Christos Stavrakakis | """Remove the user from image members.
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287 | 1e28ba40 | Christos Stavrakakis |
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288 | cda71050 | Christos Stavrakakis | Remove the specified user from the read permissions of the Pithos file.
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289 | cda71050 | Christos Stavrakakis |
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290 | cda71050 | Christos Stavrakakis | """
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291 | cda71050 | Christos Stavrakakis | image_url = self._get_image_url(image_uuid)
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292 | cda71050 | Christos Stavrakakis | self._get_image(image_url) # Assert that it is an image |
293 | cda71050 | Christos Stavrakakis | permissions = self._get_permissions(image_url)
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294 | cda71050 | Christos Stavrakakis | read = set(permissions.get("read", [])) |
295 | cda71050 | Christos Stavrakakis | assert(isinstance(remove_user, (str, unicode))) |
296 | cda71050 | Christos Stavrakakis | try:
|
297 | cda71050 | Christos Stavrakakis | read.remove(remove_user) |
298 | cda71050 | Christos Stavrakakis | except ValueError: |
299 | cda71050 | Christos Stavrakakis | return # TODO: User did not have access |
300 | cda71050 | Christos Stavrakakis | permissions["read"] = list(read) |
301 | cda71050 | Christos Stavrakakis | self._update_permissions(image_url, permissions)
|
302 | 1e28ba40 | Christos Stavrakakis | |
303 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
|
304 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
|
305 | cda71050 | Christos Stavrakakis | def replace_users(self, image_uuid, replace_users): |
306 | cda71050 | Christos Stavrakakis | """Replace image members.
|
307 | f13aab5d | Christos Stavrakakis |
|
308 | cda71050 | Christos Stavrakakis | Replace the read permissions of the Pithos files with the specified
|
309 | cda71050 | Christos Stavrakakis | users. If image is specified as public, we must preserve * permission.
|
310 | f13aab5d | Christos Stavrakakis |
|
311 | f13aab5d | Christos Stavrakakis | """
|
312 | cda71050 | Christos Stavrakakis | image_url = self._get_image_url(image_uuid)
|
313 | cda71050 | Christos Stavrakakis | image = self._get_image(image_url)
|
314 | cda71050 | Christos Stavrakakis | permissions = self._get_permissions(image_url)
|
315 | cda71050 | Christos Stavrakakis | assert(isinstance(replace_users, list)) |
316 | cda71050 | Christos Stavrakakis | permissions["read"] = replace_users
|
317 | cda71050 | Christos Stavrakakis | if image.get("is_public", False): |
318 | cda71050 | Christos Stavrakakis | permissions["read"].append("*") |
319 | cda71050 | Christos Stavrakakis | self._update_permissions(image_url, permissions)
|
320 | 1e28ba40 | Christos Stavrakakis | |
321 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
|
322 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
|
323 | cda71050 | Christos Stavrakakis | def list_users(self, image_uuid): |
324 | cda71050 | Christos Stavrakakis | """List the image members.
|
325 | cda71050 | Christos Stavrakakis |
|
326 | cda71050 | Christos Stavrakakis | List the image members, by listing all users that have read permission
|
327 | cda71050 | Christos Stavrakakis | to the corresponding Pithos file.
|
328 | cda71050 | Christos Stavrakakis |
|
329 | cda71050 | Christos Stavrakakis | """
|
330 | cda71050 | Christos Stavrakakis | image_url = self._get_image_url(image_uuid)
|
331 | cda71050 | Christos Stavrakakis | self._get_image(image_url) # Assert that it is an image |
332 | cda71050 | Christos Stavrakakis | permissions = self._get_permissions(image_url)
|
333 | cda71050 | Christos Stavrakakis | return [user for user in permissions.get('read', []) if user != '*'] |
334 | 1e28ba40 | Christos Stavrakakis | |
335 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
|
336 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
|
337 | cda71050 | Christos Stavrakakis | def update_metadata(self, image_uuid, metadata): |
338 | cda71050 | Christos Stavrakakis | """Update Image metadata."""
|
339 | cda71050 | Christos Stavrakakis | image_url = self._get_image_url(image_uuid)
|
340 | cda71050 | Christos Stavrakakis | self._get_image(image_url) # Assert that it is an image |
341 | 1e28ba40 | Christos Stavrakakis | |
342 | d58ea30a | Christos Stavrakakis | # 'is_public' metadata is translated in proper file permissions
|
343 | cda71050 | Christos Stavrakakis | is_public = metadata.pop("is_public", None) |
344 | cda71050 | Christos Stavrakakis | if is_public is not None: |
345 | cda71050 | Christos Stavrakakis | permissions = self._get_permissions(image_url)
|
346 | cda71050 | Christos Stavrakakis | read = set(permissions.get("read", [])) |
347 | cda71050 | Christos Stavrakakis | if is_public:
|
348 | cda71050 | Christos Stavrakakis | read.add("*")
|
349 | cda71050 | Christos Stavrakakis | else:
|
350 | cda71050 | Christos Stavrakakis | read.discard("*")
|
351 | cda71050 | Christos Stavrakakis | permissions["read"] = list(read) |
352 | cda71050 | Christos Stavrakakis | self._update_permissions(image_url, permissions)
|
353 | d58ea30a | Christos Stavrakakis | |
354 | d58ea30a | Christos Stavrakakis | # Extract the properties dictionary from metadata, and store each
|
355 | d58ea30a | Christos Stavrakakis | # property as a separeted, prefixed metadata
|
356 | d58ea30a | Christos Stavrakakis | properties = metadata.pop("properties", {})
|
357 | d58ea30a | Christos Stavrakakis | meta = dict([(PROPERTY_PREFIX + k, v) for k, v in properties.items()]) |
358 | d58ea30a | Christos Stavrakakis | # Also add the following metadata
|
359 | cda71050 | Christos Stavrakakis | meta.update(**metadata) |
360 | cda71050 | Christos Stavrakakis | |
361 | cda71050 | Christos Stavrakakis | self._update_meta(image_url, meta)
|
362 | 3347a30c | Georgios D. Tsoukalas | image_url = self._get_image_url(image_uuid)
|
363 | 3347a30c | Georgios D. Tsoukalas | return self._get_image(image_url) |
364 | 1e28ba40 | Christos Stavrakakis | |
365 | 2db7d9df | Christos Stavrakakis | @handle_backend_exceptions
|
366 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
|
367 | cda71050 | Christos Stavrakakis | def register(self, name, image_url, metadata): |
368 | cda71050 | Christos Stavrakakis | # Validate that metadata are allowed
|
369 | cda71050 | Christos Stavrakakis | if "id" in metadata: |
370 | cda71050 | Christos Stavrakakis | raise ValueError("Passing an ID is not supported") |
371 | cda71050 | Christos Stavrakakis | store = metadata.pop("store", "pithos") |
372 | cda71050 | Christos Stavrakakis | if store != "pithos": |
373 | cda71050 | Christos Stavrakakis | raise ValueError("Invalid store '%s'. Only 'pithos' store is" |
374 | cda71050 | Christos Stavrakakis | "supported" % store)
|
375 | cda71050 | Christos Stavrakakis | disk_format = metadata.setdefault("disk_format",
|
376 | cda71050 | Christos Stavrakakis | settings.DEFAULT_DISK_FORMAT) |
377 | cda71050 | Christos Stavrakakis | if disk_format not in settings.ALLOWED_DISK_FORMATS: |
378 | cda71050 | Christos Stavrakakis | raise ValueError("Invalid disk format '%s'" % disk_format) |
379 | cda71050 | Christos Stavrakakis | container_format =\ |
380 | cda71050 | Christos Stavrakakis | metadata.setdefault("container_format",
|
381 | cda71050 | Christos Stavrakakis | settings.DEFAULT_CONTAINER_FORMAT) |
382 | cda71050 | Christos Stavrakakis | if container_format not in settings.ALLOWED_CONTAINER_FORMATS: |
383 | cda71050 | Christos Stavrakakis | raise ValueError("Invalid container format '%s'" % |
384 | cda71050 | Christos Stavrakakis | container_format) |
385 | cda71050 | Christos Stavrakakis | |
386 | cda71050 | Christos Stavrakakis | # Validate that 'size' and 'checksum' are valid
|
387 | cda71050 | Christos Stavrakakis | account, container, object = split_url(image_url) |
388 | cda71050 | Christos Stavrakakis | |
389 | cda71050 | Christos Stavrakakis | meta = self._get_meta(image_url)
|
390 | cda71050 | Christos Stavrakakis | |
391 | cda71050 | Christos Stavrakakis | size = int(metadata.pop('size', meta['bytes'])) |
392 | cda71050 | Christos Stavrakakis | if size != meta['bytes']: |
393 | cda71050 | Christos Stavrakakis | raise ValueError("Invalid size") |
394 | cda71050 | Christos Stavrakakis | |
395 | cda71050 | Christos Stavrakakis | checksum = metadata.pop('checksum', meta['hash']) |
396 | cda71050 | Christos Stavrakakis | if checksum != meta['hash']: |
397 | cda71050 | Christos Stavrakakis | raise ValueError("Invalid checksum") |
398 | cda71050 | Christos Stavrakakis | |
399 | cda71050 | Christos Stavrakakis | # Fix permissions
|
400 | cda71050 | Christos Stavrakakis | is_public = metadata.pop('is_public', False) |
401 | cda71050 | Christos Stavrakakis | if is_public:
|
402 | cda71050 | Christos Stavrakakis | permissions = {'read': ['*']} |
403 | cda71050 | Christos Stavrakakis | else:
|
404 | cda71050 | Christos Stavrakakis | permissions = {'read': [self.user]} |
405 | cda71050 | Christos Stavrakakis | |
406 | d58ea30a | Christos Stavrakakis | # Extract the properties dictionary from metadata, and store each
|
407 | d58ea30a | Christos Stavrakakis | # property as a separeted, prefixed metadata
|
408 | d58ea30a | Christos Stavrakakis | properties = metadata.pop("properties", {})
|
409 | d58ea30a | Christos Stavrakakis | meta = dict([(PROPERTY_PREFIX + k, v) for k, v in properties.items()]) |
410 | 3a528c36 | Christos Stavrakakis | # Add creation(register) timestamp as a metadata, to avoid extra
|
411 | 3a528c36 | Christos Stavrakakis | # queries when retrieving the list of images.
|
412 | 3a528c36 | Christos Stavrakakis | meta['created_at'] = time()
|
413 | d58ea30a | Christos Stavrakakis | # Update rest metadata
|
414 | cda71050 | Christos Stavrakakis | meta.update(name=name, status='available', **metadata)
|
415 | cda71050 | Christos Stavrakakis | |
416 | cda71050 | Christos Stavrakakis | # Do the actualy update in the Pithos backend
|
417 | cda71050 | Christos Stavrakakis | self._update_meta(image_url, meta)
|
418 | cda71050 | Christos Stavrakakis | self._update_permissions(image_url, permissions)
|
419 | 62d3ea53 | Christos Stavrakakis | logger.debug("User '%s' created image '%s'('%s')", self.user, |
420 | 62d3ea53 | Christos Stavrakakis | image_url, name) |
421 | cda71050 | Christos Stavrakakis | return self._get_image(image_url) |
422 | cda71050 | Christos Stavrakakis | |
423 | 14c94c48 | Christos Stavrakakis | def _list_images(self, user=None, filters=None, params=None): |
424 | d19e8f77 | Giorgos Verigakis | filters = filters or {}
|
425 | 1e28ba40 | Christos Stavrakakis | |
426 | 14c94c48 | Christos Stavrakakis | # TODO: Use filters
|
427 | 14c94c48 | Christos Stavrakakis | # # Fix keys
|
428 | 14c94c48 | Christos Stavrakakis | # keys = [PLANKTON_PREFIX + 'name']
|
429 | 14c94c48 | Christos Stavrakakis | # size_range = (None, None)
|
430 | 14c94c48 | Christos Stavrakakis | # for key, val in filters.items():
|
431 | 14c94c48 | Christos Stavrakakis | # if key == 'size_min':
|
432 | 14c94c48 | Christos Stavrakakis | # size_range = (val, size_range[1])
|
433 | 14c94c48 | Christos Stavrakakis | # elif key == 'size_max':
|
434 | 14c94c48 | Christos Stavrakakis | # size_range = (size_range[0], val)
|
435 | 14c94c48 | Christos Stavrakakis | # else:
|
436 | 14c94c48 | Christos Stavrakakis | # keys.append('%s = %s' % (PLANKTON_PREFIX + key, val))
|
437 | 14c94c48 | Christos Stavrakakis | _images = self.backend.get_domain_objects(domain=PLANKTON_DOMAIN,
|
438 | 14c94c48 | Christos Stavrakakis | user=user) |
439 | 14c94c48 | Christos Stavrakakis | |
440 | 14c94c48 | Christos Stavrakakis | images = [] |
441 | 14c94c48 | Christos Stavrakakis | for (location, meta, permissions) in _images: |
442 | 14c94c48 | Christos Stavrakakis | image_url = "pithos://" + location
|
443 | 14c94c48 | Christos Stavrakakis | meta["modified"] = meta["version_timestamp"] |
444 | 14c94c48 | Christos Stavrakakis | images.append(image_to_dict(image_url, meta, permissions)) |
445 | 14c94c48 | Christos Stavrakakis | |
446 | 14c94c48 | Christos Stavrakakis | if params is None: |
447 | 14c94c48 | Christos Stavrakakis | params = {} |
448 | aed77afe | Christos Stavrakakis | key = itemgetter(params.get('sort_key', 'created_at')) |
449 | aed77afe | Christos Stavrakakis | reverse = params.get('sort_dir', 'desc') == 'desc' |
450 | aed77afe | Christos Stavrakakis | images.sort(key=key, reverse=reverse) |
451 | aed77afe | Christos Stavrakakis | return images
|
452 | 1e28ba40 | Christos Stavrakakis | |
453 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
|
454 | 14c94c48 | Christos Stavrakakis | def list_images(self, filters=None, params=None): |
455 | 14c94c48 | Christos Stavrakakis | return self._list_images(user=self.user, filters=filters, |
456 | 14c94c48 | Christos Stavrakakis | params=params) |
457 | 14c94c48 | Christos Stavrakakis | |
458 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
|
459 | 14c94c48 | Christos Stavrakakis | def list_shared_images(self, member, filters=None, params=None): |
460 | 14c94c48 | Christos Stavrakakis | images = self._list_images(user=self.user, filters=filters, |
461 | 14c94c48 | Christos Stavrakakis | params=params) |
462 | 14c94c48 | Christos Stavrakakis | is_shared = lambda img: not img["is_public"] and img["owner"] == member |
463 | 14c94c48 | Christos Stavrakakis | return filter(is_shared, images) |
464 | 14c94c48 | Christos Stavrakakis | |
465 | 3347a30c | Georgios D. Tsoukalas | @commit_on_success
|
466 | 14c94c48 | Christos Stavrakakis | def list_public_images(self, filters=None, params=None): |
467 | 14c94c48 | Christos Stavrakakis | images = self._list_images(user=None, filters=filters, params=params) |
468 | 14c94c48 | Christos Stavrakakis | return filter(lambda img: img["is_public"], images) |
469 | 1e28ba40 | Christos Stavrakakis | |
470 | 1e28ba40 | Christos Stavrakakis | |
471 | cda71050 | Christos Stavrakakis | class ImageBackendError(Exception): |
472 | cda71050 | Christos Stavrakakis | pass
|
473 | 1e28ba40 | Christos Stavrakakis | |
474 | 1e28ba40 | Christos Stavrakakis | |
475 | cda71050 | Christos Stavrakakis | class ImageNotFound(ImageBackendError): |
476 | cda71050 | Christos Stavrakakis | pass
|
477 | f13aab5d | Christos Stavrakakis | |
478 | f13aab5d | Christos Stavrakakis | |
479 | cda71050 | Christos Stavrakakis | class Forbidden(ImageBackendError): |
480 | cda71050 | Christos Stavrakakis | pass
|
481 | 14c94c48 | Christos Stavrakakis | |
482 | 14c94c48 | Christos Stavrakakis | |
483 | 0efb43cd | Christos Stavrakakis | class InvalidMetadata(ImageBackendError): |
484 | 0efb43cd | Christos Stavrakakis | pass
|
485 | 0efb43cd | Christos Stavrakakis | |
486 | 0efb43cd | Christos Stavrakakis | |
487 | 14c94c48 | Christos Stavrakakis | def image_to_dict(image_url, meta, permissions): |
488 | 14c94c48 | Christos Stavrakakis | """Render an image to a dictionary"""
|
489 | 14c94c48 | Christos Stavrakakis | account, container, name = split_url(image_url) |
490 | 14c94c48 | Christos Stavrakakis | |
491 | 14c94c48 | Christos Stavrakakis | image = {} |
492 | 14c94c48 | Christos Stavrakakis | if PLANKTON_PREFIX + 'name' not in meta: |
493 | 125c682c | Christos Stavrakakis | logger.warning("Image without Plankton name!! url %s meta %s",
|
494 | 125c682c | Christos Stavrakakis | image_url, meta) |
495 | 125c682c | Christos Stavrakakis | image[PLANKTON_PREFIX + "name"] = "" |
496 | 14c94c48 | Christos Stavrakakis | |
497 | 14c94c48 | Christos Stavrakakis | image["id"] = meta["uuid"] |
498 | 14c94c48 | Christos Stavrakakis | image["location"] = image_url
|
499 | 14c94c48 | Christos Stavrakakis | image["checksum"] = meta["hash"] |
500 | 3a528c36 | Christos Stavrakakis | created = meta.get("created_at", meta["modified"]) |
501 | 3a528c36 | Christos Stavrakakis | image["created_at"] = format_timestamp(created)
|
502 | 14c94c48 | Christos Stavrakakis | deleted = meta.get("deleted", None) |
503 | 14c94c48 | Christos Stavrakakis | image["deleted_at"] = format_timestamp(deleted) if deleted else "" |
504 | 14c94c48 | Christos Stavrakakis | image["updated_at"] = format_timestamp(meta["modified"]) |
505 | 14c94c48 | Christos Stavrakakis | image["size"] = meta["bytes"] |
506 | 14c94c48 | Christos Stavrakakis | image["store"] = "pithos" |
507 | 14c94c48 | Christos Stavrakakis | image['owner'] = account
|
508 | 14c94c48 | Christos Stavrakakis | |
509 | 14c94c48 | Christos Stavrakakis | # Permissions
|
510 | 14c94c48 | Christos Stavrakakis | image["is_public"] = "*" in permissions.get('read', []) |
511 | 14c94c48 | Christos Stavrakakis | |
512 | d58ea30a | Christos Stavrakakis | properties = {} |
513 | 14c94c48 | Christos Stavrakakis | for key, val in meta.items(): |
514 | 14c94c48 | Christos Stavrakakis | # Get plankton properties
|
515 | 14c94c48 | Christos Stavrakakis | if key.startswith(PLANKTON_PREFIX):
|
516 | 14c94c48 | Christos Stavrakakis | # Remove plankton prefix
|
517 | 14c94c48 | Christos Stavrakakis | key = key.replace(PLANKTON_PREFIX, "")
|
518 | 14c94c48 | Christos Stavrakakis | # Keep only those in plankton meta
|
519 | 14c94c48 | Christos Stavrakakis | if key in PLANKTON_META: |
520 | d58ea30a | Christos Stavrakakis | if key != "created_at": |
521 | 3a528c36 | Christos Stavrakakis | # created timestamp is return in 'created_at' field
|
522 | 3a528c36 | Christos Stavrakakis | image[key] = val |
523 | d58ea30a | Christos Stavrakakis | elif key.startswith(PROPERTY_PREFIX):
|
524 | d58ea30a | Christos Stavrakakis | key = key.replace(PROPERTY_PREFIX, "")
|
525 | d58ea30a | Christos Stavrakakis | properties[key] = val |
526 | d58ea30a | Christos Stavrakakis | image["properties"] = properties
|
527 | 14c94c48 | Christos Stavrakakis | |
528 | 14c94c48 | Christos Stavrakakis | return image
|
529 | 9393d4ee | Kostas Papadimitriou | |
530 | 9393d4ee | Kostas Papadimitriou | |
531 | 9393d4ee | Kostas Papadimitriou | class JSONFileBackend(object): |
532 | 9393d4ee | Kostas Papadimitriou | """
|
533 | 9393d4ee | Kostas Papadimitriou | A dummy image backend that loads available images from a file with json
|
534 | 9393d4ee | Kostas Papadimitriou | formatted content.
|
535 | 9393d4ee | Kostas Papadimitriou |
|
536 | 9393d4ee | Kostas Papadimitriou | usage:
|
537 | 9393d4ee | Kostas Papadimitriou | PLANKTON_BACKEND_MODULE = 'synnefo.plankton.backend.JSONFileBackend'
|
538 | 9393d4ee | Kostas Papadimitriou | PLANKTON_IMAGES_JSON_BACKEND_FILE = '/tmp/images.json'
|
539 | 9393d4ee | Kostas Papadimitriou |
|
540 | 9393d4ee | Kostas Papadimitriou | # loading images from an existing plankton service
|
541 | 9393d4ee | Kostas Papadimitriou | $ curl -H "X-Auth-Token: <MYTOKEN>" \
|
542 | 9393d4ee | Kostas Papadimitriou | https://cyclades.synnefo.org/plankton/images/detail | \
|
543 | 9393d4ee | Kostas Papadimitriou | python -m json.tool > /tmp/images.json
|
544 | 9393d4ee | Kostas Papadimitriou | """
|
545 | 9393d4ee | Kostas Papadimitriou | def __init__(self, userid): |
546 | 9393d4ee | Kostas Papadimitriou | self.images_file = getattr(settings, |
547 | 9393d4ee | Kostas Papadimitriou | 'PLANKTON_IMAGES_JSON_BACKEND_FILE', '') |
548 | 9393d4ee | Kostas Papadimitriou | if not os.path.exists(self.images_file): |
549 | 9393d4ee | Kostas Papadimitriou | raise Exception("Invalid plankgon images json backend file: %s", |
550 | 9393d4ee | Kostas Papadimitriou | self.images_file)
|
551 | 9393d4ee | Kostas Papadimitriou | fp = file(self.images_file) |
552 | 9393d4ee | Kostas Papadimitriou | self.images = json.load(fp)
|
553 | 9393d4ee | Kostas Papadimitriou | fp.close() |
554 | 9393d4ee | Kostas Papadimitriou | |
555 | 9393d4ee | Kostas Papadimitriou | def iter(self, *args, **kwargs): |
556 | 9393d4ee | Kostas Papadimitriou | return self.images.__iter__() |
557 | 9393d4ee | Kostas Papadimitriou | |
558 | 9393d4ee | Kostas Papadimitriou | def list_images(self, *args, **kwargs): |
559 | 9393d4ee | Kostas Papadimitriou | return self.images |
560 | 9393d4ee | Kostas Papadimitriou | |
561 | 9393d4ee | Kostas Papadimitriou | def get_image(self, image_uuid): |
562 | 9393d4ee | Kostas Papadimitriou | try:
|
563 | 9393d4ee | Kostas Papadimitriou | return filter(lambda i: i['id'] == image_uuid, self.images)[0] |
564 | 9393d4ee | Kostas Papadimitriou | except IndexError: |
565 | 9393d4ee | Kostas Papadimitriou | raise Exception("Unknown image uuid: %s" % image_uuid) |
566 | 9393d4ee | Kostas Papadimitriou | |
567 | 9393d4ee | Kostas Papadimitriou | def close(self): |
568 | 9393d4ee | Kostas Papadimitriou | pass
|
569 | 9393d4ee | Kostas Papadimitriou | |
570 | 9393d4ee | Kostas Papadimitriou | |
571 | 9393d4ee | Kostas Papadimitriou | def get_backend(): |
572 | 9393d4ee | Kostas Papadimitriou | backend_module = getattr(settings, 'PLANKTON_BACKEND_MODULE', None) |
573 | 9393d4ee | Kostas Papadimitriou | if not backend_module: |
574 | 9393d4ee | Kostas Papadimitriou | # no setting set
|
575 | 9393d4ee | Kostas Papadimitriou | return ImageBackend
|
576 | 9393d4ee | Kostas Papadimitriou | |
577 | 9393d4ee | Kostas Papadimitriou | parts = backend_module.split(".")
|
578 | 9393d4ee | Kostas Papadimitriou | module = ".".join(parts[:-1]) |
579 | 9393d4ee | Kostas Papadimitriou | cls = parts[-1]
|
580 | 9393d4ee | Kostas Papadimitriou | try:
|
581 | 9393d4ee | Kostas Papadimitriou | return getattr(importlib.import_module(module), cls) |
582 | 9393d4ee | Kostas Papadimitriou | except (ImportError, AttributeError), e: |
583 | 9393d4ee | Kostas Papadimitriou | raise ImportError("Cannot import plankton module: %s (%s)" % |
584 | 9393d4ee | Kostas Papadimitriou | (backend_module, e.message)) |