1 files changed, 91 insertions, 0 deletions
diff --git a/serial/__init__.py b/serial/__init__.py
new file mode 100644
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+++ b/serial/__init__.py
@@ -0,0 +1,91 @@
+#!/usr/bin/env python
+#
+# This is a wrapper module for different platform implementations
+#
+# This file is part of pySerial. https://github.com/pyserial/pyserial
+# (C) 2001-2020 Chris Liechti <cliechti@gmx.net>
+#
+# SPDX-License-Identifier:    BSD-3-Clause
+
+from __future__ import absolute_import
+
+import sys
+import importlib
+
+from serial.serialutil import *
+#~ SerialBase, SerialException, to_bytes, iterbytes
+
+__version__ = '3.5'
+
+VERSION = __version__
+
+# pylint: disable=wrong-import-position
+if sys.platform == 'cli':
+    from serial.serialcli import Serial
+else:
+    import os
+    # chose an implementation, depending on os
+    if os.name == 'nt':  # sys.platform == 'win32':
+        from serial.serialwin32 import Serial
+    elif os.name == 'posix':
+        from serial.serialposix import Serial, PosixPollSerial, VTIMESerial  # noqa
+    elif os.name == 'java':
+        from serial.serialjava import Serial
+    else:
+        raise ImportError("Sorry: no implementation for your platform ('{}') available".format(os.name))
+
+
+protocol_handler_packages = [
+    'serial.urlhandler',
+]
+
+
+def serial_for_url(url, *args, **kwargs):
+    """\
+    Get an instance of the Serial class, depending on port/url. The port is not
+    opened when the keyword parameter 'do_not_open' is true, by default it
+    is. All other parameters are directly passed to the __init__ method when
+    the port is instantiated.
+
+    The list of package names that is searched for protocol handlers is kept in
+    ``protocol_handler_packages``.
+
+    e.g. we want to support a URL ``foobar://``. A module
+    ``my_handlers.protocol_foobar`` is provided by the user. Then
+    ``protocol_handler_packages.append("my_handlers")`` would extend the search
+    path so that ``serial_for_url("foobar://"))`` would work.
+    """
+    # check and remove extra parameter to not confuse the Serial class
+    do_open = not kwargs.pop('do_not_open', False)
+    # the default is to use the native implementation
+    klass = Serial
+    try:
+        url_lowercase = url.lower()
+    except AttributeError:
+        # it's not a string, use default
+        pass
+    else:
+        # if it is an URL, try to import the handler module from the list of possible packages
+        if '://' in url_lowercase:
+            protocol = url_lowercase.split('://', 1)[0]
+            module_name = '.protocol_{}'.format(protocol)
+            for package_name in protocol_handler_packages:
+                try:
+                    importlib.import_module(package_name)
+                    handler_module = importlib.import_module(module_name, package_name)
+                except ImportError:
+                    continue
+                else:
+                    if hasattr(handler_module, 'serial_class_for_url'):
+                        url, klass = handler_module.serial_class_for_url(url)
+                    else:
+                        klass = handler_module.Serial
+                    break
+            else:
+                raise ValueError('invalid URL, protocol {!r} not known'.format(protocol))
+    # instantiate and open when desired
+    instance = klass(None, *args, **kwargs)
+    instance.port = url
+    if do_open:
+        instance.open()
+    return instance