Fix livereload when using serve from stdin (#56)

We must not attempt to get the file name of stdin (the current error) and we also must not try to re-read it.

Now that this case is handled specifically at `serve`, we don't need to generally expect closed files in `load_config` - it was a workaround and an insufficient one at that.

Author: oprypin

properdocs/commands/serve.py

@@ -1,10 +1,12 @@
 from __future__ import annotations
 
+import io
 import logging
 import shutil
+import sys
 import tempfile
 from os.path import isdir, isfile, join
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, BinaryIO, Callable
 from urllib.parse import urlsplit
 
 from properdocs.commands.build import build
@@ -18,7 +20,7 @@
 
 
 def serve(
-    config_file: str | None = None,
+    config_file: str | BinaryIO | None = None,
     livereload: bool = True,
     build_type: str | None = None,
     watch_theme: bool = False,
@@ -37,9 +39,22 @@ def serve(
     # Create a temporary build directory, and set some options to serve it
     site_dir = tempfile.mkdtemp(prefix='properdocs_')
 
+    get_config_file: Callable[[], str | BinaryIO | None]
+    if config_file is None or isinstance(config_file, str):
+        get_config_file = lambda: config_file
+    elif sys.stdin and config_file is sys.stdin.buffer:
+        # Stdin must be read only once, can't be reopened later.
+        config_file_content = sys.stdin.buffer.read()
+        get_config_file = lambda: io.BytesIO(config_file_content)
+    else:
+        # If closed file descriptor, reopen it through the file path instead.
+        get_config_file = lambda: (
+            config_file.name if getattr(config_file, 'closed', False) else config_file
+        )
+
     def get_config():
         config = load_config(
-            config_file=config_file,
+            config_file=get_config_file(),
             site_dir=site_dir,
             **kwargs,
         )

properdocs/config/base.py

@@ -290,9 +290,6 @@ def _open_config_file(config_file: str | IO | None) -> Iterator[IO]:
     # If it is a string, we can assume it is a path and attempt to open it.
     elif isinstance(config_file, str):
         paths_to_try = [config_file]
-    # If closed file descriptor, get file path to reopen later.
-    elif getattr(config_file, 'closed', False):
-        paths_to_try = [config_file.name]
     else:
         result_config_file = config_file
         paths_to_try = None

properdocs/tests/config/base_tests.py

@@ -118,20 +118,6 @@ def test_load_from_open_file(self, temp_path):
         # load_config will always close the file
         self.assertTrue(config_file.closed)
 
-    @tempdir()
-    def test_load_from_closed_file(self, temp_dir):
-        """
-        The `serve` command with auto-reload may pass in a closed file descriptor.
-        Ensure `load_config` reloads the closed file.
-        """
-        with open(os.path.join(temp_dir, 'properdocs.yml'), 'w') as config_file:
-            config_file.write("site_name: ProperDocs Test\ntheme: mkdocs\n")
-        os.mkdir(os.path.join(temp_dir, 'docs'))
-
-        cfg = base.load_config(config_file=config_file)
-        self.assertTrue(isinstance(cfg, defaults.ProperDocsConfig))
-        self.assertEqual(cfg.site_name, 'ProperDocs Test')
-
     @tempdir()
     def test_load_missing_required(self, temp_dir):
         """`site_name` is a required setting."""
@@ -260,7 +246,7 @@ def test_load_from_file_with_relative_paths(self, config_dir):
         docs_dir = os.path.join(config_dir, 'src')
         os.mkdir(docs_dir)
 
-        cfg = base.load_config(config_file=config_file)
+        cfg = base.load_config(config_file=config_fname)
         self.assertTrue(isinstance(cfg, defaults.ProperDocsConfig))
         self.assertEqual(cfg.site_name, 'ProperDocs Test')
         self.assertEqual(cfg.docs_dir, docs_dir)