sambacc: make FileOpener a common type

Move the private implementation of the minimal FileOpener opener type to
the opener.py module. This will allow other parts of sambacc to reuse
that opener. Update the config test to match the changes.

Signed-off-by: John Mulligan <[email protected]>

Author: phlogistonjohn

sambacc/config.py

@@ -25,7 +25,7 @@
 import sys
 import typing
 
-from .opener import Opener
+from .opener import Opener, FileOpener
 
 _VALID_VERSIONS = ["v0"]
 
@@ -155,11 +155,6 @@ def _check_config_valid(
                 raise
 
 
-class _FileOpener:
-    def open(self, path: str) -> typing.IO:
-        return _open(path, "rb")
-
-
 def read_config_files(
     fnames: list[str],
     *,
@@ -175,7 +170,7 @@ def read_config_files(
     # users will be split from the main config (for security reasons) but
     # it would be nicer to have a good merge algorithm handle everything
     # smarter at some point.
-    opener = opener or _FileOpener()
+    opener = opener or FileOpener()
     gconfig = GlobalConfig()
     readfiles = set()
     for fname in fnames:

sambacc/opener.py

@@ -43,7 +43,7 @@ def __init__(
         open_fn: typing.Optional[typing.Callable[..., typing.IO]] = None,
     ) -> None:
         self._openers = openers
-        self._open_fn = open_fn or open
+        self._open_fn = open_fn or FileOpener.open
 
     def open(self, path_or_uri: str) -> typing.IO:
         for opener in self._openers:
@@ -55,3 +55,11 @@ def open(self, path_or_uri: str) -> typing.IO:
 
     def _open(self, path: str) -> typing.IO:
         return self._open_fn(path)
+
+
+class FileOpener:
+    """Minimal opener that only supports opening local files."""
+
+    @staticmethod
+    def open(path: str) -> typing.IO:
+        return open(path, "rb")

tests/test_config.py

@@ -22,6 +22,7 @@
 import unittest
 
 import sambacc.config
+import sambacc.opener
 
 config1 = """
 {
@@ -451,7 +452,7 @@ def test_tesd_config_files_realerr_rootok(monkeypatch):
     def err_open(*args):
         raise OSError("test!")
 
-    monkeypatch.setattr(sambacc.config, "_open", err_open)
+    monkeypatch.setattr(sambacc.opener.FileOpener, "open", err_open)
     fname = "/etc/foobar"
     with pytest.raises(OSError):
         sambacc.config.read_config_files([fname])