How to use the waitress.buffers.ReadOnlyFileBasedBuffer function in waitress

def test_execute_app_returns_filewrapper_prepare_returns_True(self):
        from waitress.buffers import ReadOnlyFileBasedBuffer

        f = io.BytesIO(b"abc")
        app_iter = ReadOnlyFileBasedBuffer(f, 8192)

        def app(environ, start_response):
            start_response("200 OK", [("Content-Length", "3")])
            return app_iter

        inst = self._makeOne()
        inst.channel.server.application = app
        inst.execute()
        self.assertTrue(inst.channel.written)  # header
        self.assertEqual(inst.channel.otherdata, [app_iter])

def test_execute_app_returns_filewrapper_prepare_returns_True_nocl(self):
        from waitress.buffers import ReadOnlyFileBasedBuffer

        f = io.BytesIO(b"abc")
        app_iter = ReadOnlyFileBasedBuffer(f, 8192)

        def app(environ, start_response):
            start_response("200 OK", [])
            return app_iter

        inst = self._makeOne()
        inst.channel.server.application = app
        inst.execute()
        self.assertTrue(inst.channel.written)  # header
        self.assertEqual(inst.channel.otherdata, [app_iter])
        self.assertEqual(inst.content_length, 3)

def test_execute_app_returns_filewrapper_prepare_returns_True_badcl(self):
        from waitress.buffers import ReadOnlyFileBasedBuffer

        f = io.BytesIO(b"abc")
        app_iter = ReadOnlyFileBasedBuffer(f, 8192)

        def app(environ, start_response):
            start_response("200 OK", [])
            return app_iter

        inst = self._makeOne()
        inst.channel.server.application = app
        inst.content_length = 10
        inst.response_headers = [("Content-Length", "10")]
        inst.execute()
        self.assertTrue(inst.channel.written)  # header
        self.assertEqual(inst.channel.otherdata, [app_iter])
        self.assertEqual(inst.content_length, 3)
        self.assertEqual(dict(inst.response_headers)["Content-Length"], "3")

def _makeOne(self, file, block_size=8192):
        from waitress.buffers import ReadOnlyFileBasedBuffer

        buf = ReadOnlyFileBasedBuffer(file, block_size)
        self.buffers_to_close.append(buf)
        return buf

def test_write_soon_filewrapper(self):
        from waitress.buffers import ReadOnlyFileBasedBuffer

        f = io.BytesIO(b"abc")
        wrapper = ReadOnlyFileBasedBuffer(f, 8192)
        wrapper.prepare()
        inst, sock, map = self._makeOneWithMap()
        outbufs = inst.outbufs
        orig_outbuf = outbufs[0]
        wrote = inst.write_soon(wrapper)
        self.assertEqual(wrote, 3)
        self.assertEqual(len(outbufs), 3)
        self.assertEqual(outbufs[0], orig_outbuf)
        self.assertEqual(outbufs[1], wrapper)
        self.assertEqual(outbufs[2].__class__.__name__, "OverflowableBuffer")

def write_soon(self, data):
        if data:
            # the async mainloop might be popping data off outbuf; we can
            # block here waiting for it because we're in a task thread
            with self.outbuf_lock:
                if data.__class__ is ReadOnlyFileBasedBuffer:
                    # they used wsgi.file_wrapper
                    self.outbufs.append(data)
                    nextbuf = OverflowableBuffer(self.adj.outbuf_overflow)
                    self.outbufs.append(nextbuf)
                else:
                    self.outbufs[-1].append(data)
            # XXX We might eventually need to pull the trigger here (to
            # instruct select to stop blocking), but it slows things down so
            # much that I'll hold off for now; "server push" on otherwise
            # unbusy systems may suffer.
            return len(data)
        return 0

value = value.strip()
            mykey = rename_headers.get(key, None)
            if mykey is None:
                mykey = 'HTTP_%s' % key
            if mykey not in environ:
                environ[mykey] = value

        # the following environment variables are required by the WSGI spec
        environ['wsgi.version'] = (1, 0)
        environ['wsgi.url_scheme'] = wsgi_url_scheme
        environ['wsgi.errors'] = sys.stderr # apps should use the logging module
        environ['wsgi.multithread'] = True
        environ['wsgi.multiprocess'] = False
        environ['wsgi.run_once'] = False
        environ['wsgi.input'] = request.get_body_stream()
        environ['wsgi.file_wrapper'] = ReadOnlyFileBasedBuffer

        self.environ = environ
        return environ

def write_soon(self, data):
        if not self.connected:
            # if the socket is closed then interrupt the task so that it
            # can cleanup possibly before the app_iter is exhausted
            raise ClientDisconnected
        if data:
            # the async mainloop might be popping data off outbuf; we can
            # block here waiting for it because we're in a task thread
            with self.outbuf_lock:
                self._flush_outbufs_below_high_watermark()
                if not self.connected:
                    raise ClientDisconnected
                num_bytes = len(data)
                if data.__class__ is ReadOnlyFileBasedBuffer:
                    # they used wsgi.file_wrapper
                    self.outbufs.append(data)
                    nextbuf = OverflowableBuffer(self.adj.outbuf_overflow)
                    self.outbufs.append(nextbuf)
                    self.current_outbuf_count = 0
                else:
                    if self.current_outbuf_count > self.adj.outbuf_high_watermark:
                        # rotate to a new buffer if the current buffer has hit
                        # the watermark to avoid it growing unbounded
                        nextbuf = OverflowableBuffer(self.adj.outbuf_overflow)
                        self.outbufs.append(nextbuf)
                        self.current_outbuf_count = 0
                    self.outbufs[-1].append(data)
                    self.current_outbuf_count += num_bytes
                self.total_outbufs_len += num_bytes
                if self.total_outbufs_len >= self.adj.send_bytes:

value = value.strip()
            mykey = rename_headers.get(key, None)
            if mykey is None:
                mykey = 'HTTP_%s' % key
            if mykey not in environ:
                environ[mykey] = value

        # the following environment variables are required by the WSGI spec
        environ['wsgi.version'] = (1, 0)
        environ['wsgi.url_scheme'] = wsgi_url_scheme
        environ['wsgi.errors'] = sys.stderr # apps should use the logging module
        environ['wsgi.multithread'] = True
        environ['wsgi.multiprocess'] = False
        environ['wsgi.run_once'] = False
        environ['wsgi.input'] = request.get_body_stream()
        environ['wsgi.file_wrapper'] = ReadOnlyFileBasedBuffer

        self.environ = environ
        return environ