10 # FOR A PARTICULAR PURPOSE. |
10 # FOR A PARTICULAR PURPOSE. |
11 # |
11 # |
12 |
12 |
13 __docformat__ = 'restructuredtext' |
13 __docformat__ = 'restructuredtext' |
14 |
14 |
15 |
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16 # import standard library |
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17 |
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18 # import interfaces |
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19 from z3c.form.interfaces import IFileWidget as IBaseFileWidget |
15 from z3c.form.interfaces import IFileWidget as IBaseFileWidget |
20 from zope.annotation.interfaces import IAttributeAnnotatable |
16 from zope.annotation.interfaces import IAttributeAnnotatable |
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17 from zope.interface import Attribute, Interface, implementer |
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18 from zope.lifecycleevent import ObjectModifiedEvent |
21 from zope.lifecycleevent.interfaces import IObjectModifiedEvent |
19 from zope.lifecycleevent.interfaces import IObjectModifiedEvent |
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20 from zope.schema import Bytes, BytesLine, Choice, Int, Text, TextLine |
22 from zope.schema.interfaces import IBytes |
21 from zope.schema.interfaces import IBytes |
23 |
22 |
24 # import packages |
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25 from zope.interface import implementer, Interface, Attribute |
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26 from zope.lifecycleevent import ObjectModifiedEvent |
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27 from zope.schema import Bytes, BytesLine, Int, Text, TextLine, Choice |
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28 |
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29 from pyams_file import _ |
23 from pyams_file import _ |
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24 |
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25 |
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26 # |
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27 # Blobs references manager |
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28 # |
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29 |
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30 class IBlobReferenceManager(Interface): |
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31 """Blobs references manager |
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32 |
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33 This utility interface is used to manage references to blobs: each file contains a |
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34 link to a ZODB "Blob" object which is used to store it's data; when a content is duplicated, |
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35 all it's blobs references are updated but the blob itself is not duplicated to reduce space usage. |
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36 As long as a blob data is not modified, the same content can be shared between several versions |
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37 of a same content. So it's only when all references to a given blob have been removed that |
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38 the blob file is deleted and can be garbaged collected. |
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39 """ |
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40 |
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41 def add_reference(self, blob, reference): |
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42 """Add a reference to given blob""" |
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43 |
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44 def drop_reference(self, blob, reference): |
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45 """Remove reference from given blob |
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46 |
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47 Blob is deleted if no more referenced. |
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48 """ |
30 |
49 |
31 |
50 |
32 # |
51 # |
33 # Main file objects interfaces |
52 # Main file objects interfaces |
34 # |
53 # |
60 def get_size(self): |
79 def get_size(self): |
61 """Returns the byte-size of object's data""" |
80 """Returns the byte-size of object's data""" |
62 |
81 |
63 def get_blob(self, mode='r'): |
82 def get_blob(self, mode='r'): |
64 """Get Blob file associated with this object""" |
83 """Get Blob file associated with this object""" |
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84 |
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85 def add_blob_reference(self, reference): |
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86 """Add a reference to file internal blob""" |
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87 |
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88 def free_blob(self): |
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89 """Free blob associated with this object""" |
65 |
90 |
66 |
91 |
67 class IMediaFile(IFile): |
92 class IMediaFile(IFile): |
68 """Multimedia file""" |
93 """Multimedia file""" |
69 |
94 |