Add opcode parameter descriptions

These will be used in automatically generated parts of the RAPI
documentation. Not all opcodes are documented so far, but each added
opcode's parameters need to be fully documented (verified by an
assertion).

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

test/ganeti.opcodes_unittest.py

@@ -30,6 +30,7 @@ from ganeti import opcodes
 from ganeti import ht
 from ganeti import constants
 from ganeti import errors
+from ganeti import compat
 
 import testutils
 
@@ -156,12 +157,17 @@ class TestOpcodes(unittest.TestCase):
         self.assert_(test is None or test is ht.NoType or callable(test),
                      msg=("Invalid type check for %s.%s" %
                           (cls.OP_ID, attr_name)))
-        self.assertTrue(doc is None)
+        self.assertTrue(doc is None or isinstance(doc, basestring))
 
         if callable(aval):
           self.assertFalse(callable(aval()),
                            msg="Default value returned by function is callable")
 
+      # If any parameter has documentation, all others need to have it as well
+      has_doc = [doc is not None for (_, _, _, doc) in cls.OP_PARAMS]
+      self.assertTrue(not compat.any(has_doc) or compat.all(has_doc),
+                      msg="%s does not document all parameters" % cls)
+
   def testValidateNoModification(self):
     class OpTest(opcodes.OpCode):
       OP_PARAMS = [