Make optional tryton dependency. Add required/supported versions in setup and documentation

doc/index.rst

@@ -11,10 +11,10 @@ Installation
 
 This extension requires the following packages:
 
-- Sphinx 1.2
-- proteus
+- Sphinx >= 1.2
+- proteus 3.2.x
 - path.py
-- tryton
+- tryton 3.2.x (optional if you don't need ``view`` directive)
 
 Use ``pip`` to install this extension straight from the Python Package Index::
 

setup.py

@@ -8,14 +8,17 @@ with open('README') as stream:
 
 requires = [
     'path.py',
-    'proteus',
+    'proteus>=3.2, <3.4',
     'simplejson',
     'Sphinx>=1.0b2',
     ]
+extra_require = {
+    'view directive': 'tryton>=3.2, <3.4',
+    }
 
 setup(
     name='trydoc',
-    version='0.6',
+    version='0.7',
     url='https://bitbucket.org/nantic/trydoc',
     download_url='http://pypi.python.org/pypi/trydoc',
     license='BSD',
@@ -46,5 +49,6 @@ setup(
         ],
     },
     install_requires=requires,
+    extras_require=extra_require,
     namespace_packages=['sphinxcontrib'],
 )

sphinxcontrib/trydoc/__init__.py

@@ -22,16 +22,17 @@ from docutils.transforms import Transform
 from sphinx.util.compat import Directive
 
 import proteus
-import tryton
 try:
     import gtk
     import gobject
     import signal
+    import tryton
 except ImportError, e:
     print >> sys.stderr, ("gtk importation error (%s). Screenshots feature "
         "will not be available.") % e
     gtk = None
     gobject = None
+    tryton = None
 
 
 screenshot_files = []
@@ -222,6 +223,7 @@ class ViewDirective(Image):
     def run(self):
         assert gtk is not None, "gtk not imported"
         assert gobject is not None, "gobject not imported"
+        assert tryton is not None, "tryton not imported"
 
         env = self.state.document.settings.env
         if 'class' in self.options: