Use setuptools extras_require to offer paramiko[gssapi]1311-int

2 files changed, 33 insertions, 10 deletions

diff --git a/setup.py b/setup.py
index e6c4a077..cf063c44 100644
--- a/setup.py
+++ b/setup.py
@@ -74,4 +74,11 @@ setup(
         "Programming Language :: Python :: 3.8",
     ],
     install_requires=["bcrypt>=3.1.3", "cryptography>=2.5", "pynacl>=1.0.1"],
+    extras_require={
+        "gssapi": [
+            "pyasn1>=0.1.7",
+            'gssapi>=1.4.1;platform_system!="Windows"',
+            'pywin32>=2.1.8;platform_system=="Windows"',
+        ]
+    },
 )
diff --git a/sites/www/installing.rst b/sites/www/installing.rst
index 1e50e685..cffdba5f 100644
--- a/sites/www/installing.rst
+++ b/sites/www/installing.rst
@@ -95,11 +95,33 @@ In general, you'll need one of the following setups:
 Optional dependencies for GSS-API / SSPI / Kerberos
 ===================================================
 
-In order to use GSS-API/Kerberos & related functionality, a couple of
-additional dependencies are required:
+In order to use GSS-API/Kerberos & related functionality, additional
+dependencies are required. It hopefully goes without saying but **all
+platforms** need **a working installation of GSS-API itself**, e.g. Heimdal.
+
+.. note::
+    If you use Microsoft SSPI for kerberos authentication and credential
+    delegation, make sure that the target host is trusted for delegation in the
+    active directory configuration. For details see:
+    http://technet.microsoft.com/en-us/library/cc738491%28v=ws.10%29.aspx
+
+The ``gssapi`` "extra" install flavor
+-------------------------------------
+
+If you're installing via ``pip`` (recommended), you should be able to get the
+optional Python package requirements by changing your installation to refer to
+``paramiko[gssapi]`` (from simply ``paramiko``), e.g.::
+
+    pip install "paramiko[gssapi]"
+
+(Or update your ``requirements.txt``, or etc.)
+
+Manual dependency installation
+------------------------------
+
+If you're not using ``pip`` or your ``pip`` is too old to support the "extras"
+functionality, the optional dependencies are as follows:
 
-* It hopefully goes without saying but **all platforms** need **a working
-  installation of GSS-API itself**, e.g. Heimdal.
 * All platforms need `pyasn1 <https://pypi.org/project/pyasn1/>`_ ``0.1.7`` or
   later.
 * **Unix** needs: `gssapi <https://pypi.org/project/gssapi/>`__ ``1.4.1`` or better.
@@ -111,9 +133,3 @@ additional dependencies are required:
 
 * **Windows** needs `pywin32 <https://pypi.python.org/pypi/pywin32>`_ ``2.1.8``
   or better.
-
-.. note::
-    If you use Microsoft SSPI for kerberos authentication and credential
-    delegation, make sure that the target host is trusted for delegation in the
-    active directory configuration. For details see:
-    http://technet.microsoft.com/en-us/library/cc738491%28v=ws.10%29.aspx