Initial Commit

lib/cherrypy/lib/__init__.py

@@ -0,0 +1,85 @@
+"""CherryPy Library"""
+
+# Deprecated in CherryPy 3.2 -- remove in CherryPy 3.3
+from cherrypy.lib.reprconf import unrepr, modules, attributes
+
+def is_iterator(obj):
+    '''Returns a boolean indicating if the object provided implements
+     the iterator protocol (i.e. like a generator). This will return
+     false for objects which iterable, but not iterators themselves.'''
+    from types import GeneratorType
+    if isinstance(obj, GeneratorType):
+        return True
+    elif not hasattr(obj, '__iter__'):
+        return False
+    else:
+        # Types which implement the protocol must return themselves when
+        # invoking 'iter' upon them.
+        return iter(obj) is obj
+        
+def is_closable_iterator(obj):
+    
+    # Not an iterator.
+    if not is_iterator(obj):
+        return False
+    
+    # A generator - the easiest thing to deal with.
+    import inspect
+    if inspect.isgenerator(obj):
+        return True
+    
+    # A custom iterator. Look for a close method...
+    if not (hasattr(obj, 'close') and callable(obj.close)):
+        return False
+    
+    #  ... which doesn't require any arguments.
+    try:
+        inspect.getcallargs(obj.close)
+    except TypeError:
+        return False
+    else:
+        return True
+
+class file_generator(object):
+
+    """Yield the given input (a file object) in chunks (default 64k). (Core)"""
+
+    def __init__(self, input, chunkSize=65536):
+        self.input = input
+        self.chunkSize = chunkSize
+
+    def __iter__(self):
+        return self
+
+    def __next__(self):
+        chunk = self.input.read(self.chunkSize)
+        if chunk:
+            return chunk
+        else:
+            if hasattr(self.input, 'close'):
+                self.input.close()
+            raise StopIteration()
+    next = __next__
+
+
+def file_generator_limited(fileobj, count, chunk_size=65536):
+    """Yield the given file object in chunks, stopping after `count`
+    bytes has been emitted.  Default chunk size is 64kB. (Core)
+    """
+    remaining = count
+    while remaining > 0:
+        chunk = fileobj.read(min(chunk_size, remaining))
+        chunklen = len(chunk)
+        if chunklen == 0:
+            return
+        remaining -= chunklen
+        yield chunk
+
+
+def set_vary_header(response, header_name):
+    "Add a Vary header to a response"
+    varies = response.headers.get("Vary", "")
+    varies = [x.strip() for x in varies.split(",") if x.strip()]
+    if header_name not in varies:
+        varies.append(header_name)
+    response.headers['Vary'] = ", ".join(varies)