add Content-Length header

src/suou/sass.py

@@ -11,7 +11,7 @@ from sass import CompileError
 from sassutils.builder import Manifest
 from importlib.metadata import version as _get_version
 
-from .codecs import quote_css_string
+from .codecs import quote_css_string, want_bytes
 from .validators import must_be
 from .asgi import _MiddlewareFactory, ASGIApp, ASGIReceive, ASGIScope, ASGISend
 from . import __version__ as _suou_version
@@ -83,16 +83,7 @@ class SassAsyncMiddleware(_MiddlewareFactory):
                     break
                 except CompileError as e:
                     logger.error(str(e))
-                    await send({
+                    resp_body = '\n'.join([
-                        'type': 'http.response.start',
-                        'status': self.error_status,
-                        'headers': [
-                            (b'Content-Type', b'text/css; charset=utf-8'),
-                        ]
-                    })
-                    await send({
-                        'type': 'http.response.body',
-                        'body': '\n'.join([
                         '/*',
                         str(e),
                         '***',
@@ -109,6 +100,18 @@ class SassAsyncMiddleware(_MiddlewareFactory):
                         '  user-select: text;'
                         '}'
                     ]).encode('utf-8')
+
+                    await send({
+                        'type': 'http.response.start',
+                        'status': self.error_status,
+                        'headers': [
+                            (b'Content-Type', b'text/css; charset=utf-8'),
+                            (b'Content-Length', want_bytes(f'{len(resp_body)}'))
+                        ]
+                    })
+                    await send({
+                        'type': 'http.response.body',
+                        'body': resp_body
                     })
 
                 async def _read_file(path):
@@ -129,6 +132,7 @@ class SassAsyncMiddleware(_MiddlewareFactory):
                     'status': 200,
                     'headers': [
                         (b'Content-Type', b'text/css; charset=utf-8'),
+                        (b'Content-Length', want_bytes(f'{len(resp_body)}'))
                     ]
                 })