[PATCH-next 25/40] lnst.Controller.Requirements: add RecipeParam class

From: Ondrej Lichtner <olichtne(a)redhat.com&gt;

RecipeParam class is a Param class that points (by name) to a different
Param object.

This can be used to parametrize the Requirements of a Recipe using it's
parameters, e.g. driver value.

Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
---
 lnst/Controller/Recipe.py       | 11 +++++---
 lnst/Controller/Requirements.py | 47 ++++++++++++++++++++++++++++++++-
 lnst/Controller/__init__.py     |  2 +-
 3 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/lnst/Controller/Recipe.py b/lnst/Controller/Recipe.py
index ddd8016..080dd46 100644
--- a/lnst/Controller/Recipe.py
+++ b/lnst/Controller/Recipe.py
@@ -87,9 +87,7 @@ class BaseRecipe(object):
         self.params = Parameters()
         for attr in dir(self):
             val = getattr(self, attr)
-            if isinstance(val, HostReq):
-                setattr(self.req, attr, copy.deepcopy(val))
-            elif isinstance(val, Param):
+            if isinstance(val, Param):
                 if attr in kwargs:
                     param_val = kwargs.pop(attr)
                     param_val = val.type_check(param_val)
@@ -103,6 +101,13 @@ class BaseRecipe(object):
                             raise RecipeError("Parameter {} is mandatory"
                                               .format(attr))
 
+        for attr in dir(self):
+            val = getattr(self, attr)
+            if isinstance(val, HostReq):
+                new_val = copy.deepcopy(val)
+                new_val.reinit_with_params(self.params)
+                setattr(self.req, attr, new_val)
+
         if len(kwargs):
             for key in kwargs.keys():
                 raise RecipeError("Unknown parameter {}".format(key))
diff --git a/lnst/Controller/Requirements.py b/lnst/Controller/Requirements.py
index 1d2ea6f..1337df0 100644
--- a/lnst/Controller/Requirements.py
+++ b/lnst/Controller/Requirements.py
@@ -20,12 +20,18 @@ __author__ = """
 olichtne(a)redhat.com (Ondrej Lichtner)
 """
 
+import copy
 from lnst.Common.LnstError import LnstError
-from lnst.Common.Parameters import Parameters
+from lnst.Common.Parameters import Parameters, Param
 
 class RequirementError(LnstError):
     pass
 
+class RecipeParam(Param):
+    def __init__(self, name, mandatory=False, **kwargs):
+        self.name = name
+        super(RecipeParam, self).__init__(mandatory, **kwargs)
+
 class HostReq(object):
     """Specifies a Slave machine requirement
 
@@ -48,6 +54,27 @@ class HostReq(object):
                 raise RequirementError("'params' is a reserved
keyword.")
             setattr(self.params, name, val)
 
+    def reinit_with_params(self, recipe_params):
+        for name, val in self.params:
+            if isinstance(val, RecipeParam):
+                if val.name in recipe_params:
+                    new_val = getattr(recipe_params, val.name)
+                    setattr(self.params, name, new_val)
+                else:
+                    try:
+                        new_val = copy.deepcopy(val.default)
+                        setattr(self.params, name, new_val)
+                    except AttributeError:
+                        if val.mandatory:
+                            raise RequirementError(
+                                    "Recipe parameter {} is mandatory for Recipe
Requirements parameter {}"
+                                    .format(val.name, name))
+                        else:
+                            delattr(self.params, name)
+
+        for name, dev_req in self:
+            dev_req.reinit_with_params(recipe_params)
+
     def __iter__(self):
         for x in dir(self):
             val = getattr(self, x)
@@ -86,6 +113,24 @@ class DeviceReq(object):
                 raise RequirementError("'params' is a reserved
keyword.")
             setattr(self.params, name, val)
 
+    def reinit_with_params(self, recipe_params):
+        for name, val in self.params:
+            if isinstance(val, RecipeParam):
+                if val.name in recipe_params:
+                    new_val = getattr(recipe_params, val.name)
+                    setattr(self.params, name, new_val)
+                else:
+                    try:
+                        new_val = copy.deepcopy(val.default)
+                        setattr(self.params, name, new_val)
+                    except AttributeError:
+                        if val.mandatory:
+                            raise RequirementError(
+                                    "Recipe parameter {} is mandatory for Recipe
Requirements parameter {}"
+                                    .format(val.name, name))
+                        else:
+                            delattr(self.params, name)
+
     def _to_dict(self):
         res = {'network': self.label,
                'params': self.params._to_dict()}
diff --git a/lnst/Controller/__init__.py b/lnst/Controller/__init__.py
index 2dbb60f..106bb91 100644
--- a/lnst/Controller/__init__.py
+++ b/lnst/Controller/__init__.py
@@ -1,4 +1,4 @@
 from lnst.Controller.Controller import Controller
 from lnst.Controller.Recipe import BaseRecipe
-from lnst.Controller.Requirements import HostReq, DeviceReq
+from lnst.Controller.Requirements import HostReq, DeviceReq, RecipeParam
 from lnst.Controller.NetNamespace import NetNamespace
-- 
2.17.0