Mercurial > repos > shellac > guppy_basecaller
annotate env/lib/python3.7/site-packages/cachecontrol/filewrapper.py @ 0:26e78fe6e8c4 draft
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
author | shellac |
---|---|
date | Sat, 02 May 2020 07:14:21 -0400 |
parents | |
children |
rev | line source |
---|---|
0
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
1 from io import BytesIO |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
2 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
3 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
4 class CallbackFileWrapper(object): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
5 """ |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
6 Small wrapper around a fp object which will tee everything read into a |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
7 buffer, and when that file is closed it will execute a callback with the |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
8 contents of that buffer. |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
9 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
10 All attributes are proxied to the underlying file object. |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
11 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
12 This class uses members with a double underscore (__) leading prefix so as |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
13 not to accidentally shadow an attribute. |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
14 """ |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
15 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
16 def __init__(self, fp, callback): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
17 self.__buf = BytesIO() |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
18 self.__fp = fp |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
19 self.__callback = callback |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
20 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
21 def __getattr__(self, name): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
22 # The vaguaries of garbage collection means that self.__fp is |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
23 # not always set. By using __getattribute__ and the private |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
24 # name[0] allows looking up the attribute value and raising an |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
25 # AttributeError when it doesn't exist. This stop thigns from |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
26 # infinitely recursing calls to getattr in the case where |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
27 # self.__fp hasn't been set. |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
28 # |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
29 # [0] https://docs.python.org/2/reference/expressions.html#atom-identifiers |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
30 fp = self.__getattribute__('_CallbackFileWrapper__fp') |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
31 return getattr(fp, name) |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
32 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
33 def __is_fp_closed(self): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
34 try: |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
35 return self.__fp.fp is None |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
36 except AttributeError: |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
37 pass |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
38 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
39 try: |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
40 return self.__fp.closed |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
41 except AttributeError: |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
42 pass |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
43 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
44 # We just don't cache it then. |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
45 # TODO: Add some logging here... |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
46 return False |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
47 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
48 def _close(self): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
49 if self.__callback: |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
50 self.__callback(self.__buf.getvalue()) |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
51 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
52 # We assign this to None here, because otherwise we can get into |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
53 # really tricky problems where the CPython interpreter dead locks |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
54 # because the callback is holding a reference to something which |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
55 # has a __del__ method. Setting this to None breaks the cycle |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
56 # and allows the garbage collector to do it's thing normally. |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
57 self.__callback = None |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
58 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
59 def read(self, amt=None): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
60 data = self.__fp.read(amt) |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
61 self.__buf.write(data) |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
62 if self.__is_fp_closed(): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
63 self._close() |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
64 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
65 return data |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
66 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
67 def _safe_read(self, amt): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
68 data = self.__fp._safe_read(amt) |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
69 if amt == 2 and data == b'\r\n': |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
70 # urllib executes this read to toss the CRLF at the end |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
71 # of the chunk. |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
72 return data |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
73 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
74 self.__buf.write(data) |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
75 if self.__is_fp_closed(): |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
76 self._close() |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
77 |
26e78fe6e8c4
"planemo upload commit c699937486c35866861690329de38ec1a5d9f783"
shellac
parents:
diff
changeset
|
78 return data |