1. 03 Mar, 2015 2 commits
    • Kirill Smelkov's avatar
      BigFile: .data can be BTreeData or None or (possibly non-empty) str · f54e3fa6
      Kirill Smelkov authored
      Current BigFile code in many places assumes .data property is either
      None or BTreeData instance. But as already shown in 4d8f0c33 (BigFile:
      Fix non-range download of just created big file) this is not true and
      .data can be an str.
      
      This leads to situations where code wants to act on an str, like on a
      BTreeData instance, e.g.
      
          def _range_request_handler():
              ...
      
              if data is not None:
                  RESPONSE.setHeader('Last-Modified', rfc1123_date(data._p_mtime))
      
      or
      
          def _read_data(... data=None):
              ...
      
              if data is None:
                  btree = BTreeData()
              else:
                  btree = data
      
              ...
              btree.write(...)
      
      and other places, and in all those situation we'll get AttributeError
      (str has neither ._p_mtime nor .write) and it will crash.
      
      ~~~~
      
      .data can be str at least because '' is the default value for `data`
      field in Data property sheet. From this proposition the code could be
      reorganised to work in "data is either BTreeData or empty (= None or '')"
      
      But we discussed with Romain and his idea is that non empty strings have
      to be too supported because of compatibility reasons and because of
      desire to support possible future automatic File-based documents
      migration to BigFiles.
      
      From this perspective for BigFile the invariant thus
      
          .data is either BTreeData or str (empty or not) or None.
      
      This patch goes through whole BigFile code and corrects places to either
      properly support str case, or None (in e.g. computing len(data) in
      index_html).
      
      In _read_data() if data is previously str - that means we are appending
      content to this file and thus it is a good idea to first convert str
      (empty or not) to BTreeData and then proceed with appending.
      Helped-by: Vincent Pelletier's avatarVincent Pelletier <vincent@nexedi.com>
      Reviewed-by: Romain Courteaud's avatarRomain Courteaud <romain@nexedi.com>
      f54e3fa6
    • Kirill Smelkov's avatar
      BigFile: Factor out "get .data mtime" into helper · 28225e1b
      Kirill Smelkov authored
      Since .data can be BTreeData or None (or as we'll see next and str),
      ._p_mtime() is not always defined on it and in several places current
      code has branches from where to get it.
      
      Move this logic out to a separate helper and the code which needs to
      know mtime gets streamlined.
      Suggested-by: Vincent Pelletier's avatarVincent Pelletier <vincent@nexedi.com>
      28225e1b
  2. 02 Mar, 2015 1 commit
  3. 23 Feb, 2015 1 commit
    • Kirill Smelkov's avatar
      BigFile: Fix non-range download of just created big file · 4d8f0c33
      Kirill Smelkov authored
      If in erp5 I go to big_file_module and 'Add Big File' action and then try to
      download just-created empty bigfile I get a crash:
      
          curl ... --data 'format=raw'  http://localhost:8889/erp5/big_file_module/18
      
          ...
          <h2>Site Error</h2>
      
          <p>An error was encountered while publishing this
           resource.</p>
      
          <p>
            <strong>Error Type:
              AttributeError
            </strong>
            <br />
            <strong>Error Value:
              'str' object has no attribute 'iterate'
            </strong>
            <br />
          </p>
      
      with exception traceback
      
          Traceback (innermost last):
            Module ZPublisher.Publish, line 138, in publish
              request, bind=1)
            Module ZPublisher.mapply, line 77, in mapply
              if debug is not None: return debug(object,args,context)
            Module ZPublisher.Publish, line 48, in call_object
              result=apply(object,args) # Type s<cr> to step into published object.
            Module Products.ERP5.Document.BigFile, line 297, in index_html
              for chunk in data.iterate():
          AttributeError: 'str' object has no attribute 'iterate'
      
      I've compared BigFile code with the sample place in File code from Zope/src/OFS
      (which is base class for BigFile)
      
          https://github.com/zopefoundation/Zope/blob/2.13/src/OFS/Image.py#L420
      
      and in index_html(), if we requested the data itself, there it sees whether
      self.data is either
      
          1) simply bytes (= str in python2), or
      
          2) linked-list of Pdata
      
      and in BigFile we currently miss handling 1) case.
      
      ~~~~
      
      BigFile, it looks, was copied-and-modified from Zope.OFS.Image.File first in
      65121be7 (Support streaming big file in DMS.) Then in index_html download there
      was only an 'iterate over btree chunks' case. Later in dff53681 (Get
      modification date from btree.) a case for
      
          if data is None:
            return ''
      
      was added before btree iteration.
      
      Here we also restore original Zope code for returning file content if it is
      string instance directly, because as it is experimentally observed, that case
      can also happen.
      
      The patch does not add tests, because currently BigFile class does not have
      tests at all (at least I could not find them).
      Reviewed-by: Romain Courteaud's avatarRomain Courteaud <romain@nexedi.com>
      4d8f0c33
  4. 21 Feb, 2015 3 commits
  5. 18 Feb, 2015 1 commit
  6. 17 Feb, 2015 30 commits
  7. 16 Feb, 2015 2 commits