BigFile: fix

bt5/erp5_big_file/TestTemplateItem/portal_components/test.erp5.testBigFile.py

@@ -28,6 +28,7 @@ from cStringIO import StringIO
 
 from ZPublisher.HTTPRequest import HTTPRequest
 from ZPublisher.HTTPResponse import HTTPResponse
+from ZPublisher.Iterators import IUnboundStreamIterator
 from Products.ERP5Type.tests.ERP5TypeTestCase import ERP5TypeTestCase
 from Products.ERP5Type.BTreeData import BTreeData
 
@@ -102,6 +103,13 @@ class TestBigFile(ERP5TypeTestCase):
   # check that object (document) method corresponding to request returns
   # result, with expected response body, status and headers
   def checkRequest(self, document, request, kw, result, body, status, header_dict):
+    assert type(result) is str
+    assert type(body) is str
+    # - result corresponds to the content returned as a string;
+    # - body corresponds to the content returned inside a stream iterator.
+    # We can't have both at the same time.
+    assert not(bool(result) == bool(body) == True)
+
     # request -> method to call
     method_name = request['REQUEST_METHOD']
     if method_name == 'GET':
@@ -112,18 +120,18 @@ class TestBigFile(ERP5TypeTestCase):
     # like in ZPublisher - returned RESPONSE means empty
     if ret is request.RESPONSE:
       ret = ''
-    self.assertEqual(ret,       result)
+    elif IUnboundStreamIterator.providedBy(ret):
+      ret = ''.join(ret)
     self.assertEqual(status, request.RESPONSE.getStatus())
     for h,v in header_dict.items():
       rv = request.RESPONSE.getHeader(h)
       self.assertEqual(v, rv, '%s: %r != %r' % (h, v, rv))
-
-    # force response flush to its stdout
-    request.RESPONSE.write('')
-    # body and headers are delimited by empty line (RFC 2616, 4.1)
-    response_body = request.RESPONSE.stdout.getvalue().split('\r\n\r\n', 1)[1]
-    self.assertEqual(body, response_body)
-
+    if result:
+      self.assertEqual(ret, result)
+    elif body:
+      self.assertEqual(ret, body)
+    else:
+      self.assertEqual(ret, '')
 
   # basic tests for working with BigFile via its public interface
   def testBigFile_01_Basic(self):
@@ -356,4 +364,3 @@ class TestBigFile(ERP5TypeTestCase):
 
 
   # TODO write big data to file and ensure it still works
-  # TODO test streaming works in chunks

product/ERP5/Document/BigFile.py

@@ -18,6 +18,7 @@ from cStringIO import StringIO
 from AccessControl import ClassSecurityInfo
 from Products.ERP5Type import Permissions, PropertySheet
 from Products.ERP5Type.Base import removeIContentishInterface
+from Products.ERP5Type.Utils import IterableAsStreamIterator
 from Products.ERP5.Document.File import File, _MARKER
 from Products.ERP5Type.BTreeData import BTreeData
 from ZPublisher.HTTPRequest import FileUpload
@@ -214,7 +215,7 @@ class BigFile(File):
           RESPONSE.setHeader('Content-Type', self.content_type)
           RESPONSE.setHeader('Content-Length', self.getSize())
           RESPONSE.setStatus(416)
-          return True
+          return ''
 
         ranges = HTTPRangeSupport.expandRanges(ranges, self.getSize())
 
@@ -233,11 +234,8 @@ class BigFile(File):
 
           # NOTE data cannot be None here (if it is - ranges are not satisfiable)
           if isinstance(data, str):
-            RESPONSE.write(data[start:end])
-            return True
-          for chunk in data.iterate(start, end-start):
-            RESPONSE.write(chunk)
-          return True
+            return data[start:end]
+          return IterableAsStreamIterator(data.iterate(start, size), size)
 
         else:
           boundary = choose_boundary()
@@ -266,33 +264,35 @@ class BigFile(File):
                   draftprefix, boundary))
           RESPONSE.setStatus(206) # Partial content
 
+          self_content_type = self.content_type
+          self_getSize = self.getSize()
+          def generator():
             for start, end in ranges:
-            RESPONSE.write('\r\n--%s\r\n' % boundary)
-            RESPONSE.write('Content-Type: %s\r\n' %
-                self.content_type)
-            RESPONSE.write(
-                'Content-Range: bytes %d-%d/%d\r\n\r\n' % (
-                    start, end - 1, self.getSize()))
+              yield '\r\n--%s\r\n' % boundary
+              yield 'Content-Type: %s\r\n' % self.content_type
+              yield 'Content-Range: bytes %d-%d/%d\r\n\r\n' % (
+                start, end - 1, self_getSize)
 
               # NOTE data cannot be None here (if it is - ranges are not satisfiable)
               if isinstance(data, str):
-              RESPONSE.write(data[start:end])
-
+                yield data[start:end]
               else:
-              for chunk in data.iterate(start, end-start):
-                RESPONSE.write(chunk)
+                for chunk in data.iterate(start, end - start):
+                  # BBB: Python 3.3+ yield from
+                  yield chunk
 
-          RESPONSE.write('\r\n--%s--\r\n' % boundary)
-          return True
+            yield '\r\n--%s--\r\n' % boundary
+          return IterableAsStreamIterator(generator(), size)
 
   security.declareProtected(Permissions.View, 'index_html')
   def index_html(self, REQUEST, RESPONSE, format=_MARKER, inline=_MARKER, **kw):
     """
       Support streaming
     """
-    if self._range_request_handler(REQUEST, RESPONSE):
-      # we served a chunk of content in response to a range request.
-      return ''
+    response_iterable = self._range_request_handler(REQUEST, RESPONSE)
+    if response_iterable is not None:
+      # we serve a chunk of content in response to a range request.
+      return response_iterable
 
     web_cache_kw = kw.copy()
     if format is not _MARKER:
@@ -327,9 +327,7 @@ class BigFile(File):
     if isinstance(data, str):
       RESPONSE.setBase(None)
       return data
-    for chunk in data.iterate():
-      RESPONSE.write(chunk)
-    return ''
+    return IterableAsStreamIterator(data.iterate(), len(data))
 
   security.declareProtected(Permissions.ModifyPortalContent,'PUT')
   def PUT(self, REQUEST, RESPONSE):

product/ERP5Type/Utils.py

@@ -58,6 +58,9 @@ from Products.PageTemplates.Expressions import getEngine
 from Products.PageTemplates.Expressions import SecureModuleImporter
 from Products.ZCatalog.Lazy import LazyMap
 
+from zope.interface import implementer
+from ZPublisher.Iterators import IStreamIterator
+
 try:
   import chardet
 except ImportError:
@@ -1795,3 +1798,24 @@ def formatRFC822Headers(headers):
         vallines = linesplit.split(str(value))
       munged.append('%s: %s' % (key, '\r\n  '.join(vallines)))
   return '\r\n'.join(munged)
+
+#####################################################
+# WSGI/Medusa compatibility
+#####################################################
+
+@implementer(IStreamIterator)
+class IterableAsStreamIterator:
+  def __init__(self, iterable, content_length):
+    self.iterable = iterable
+    self.content_length = content_length
+
+  def __iter__(self):
+    return self
+
+  def __len__(self):
+    return self.content_length
+
+  def next(self):
+    for chunk in self.iterable:
+      return chunk
+    raise StopIteration