interpolation of config readers extended with `%(known/parameter)s`.

(means last known option with name `parameter`).

ChangeLog

@@ -19,6 +19,8 @@ ver. 0.9.2 (2014/XX/XXX) - wanna-be-released
 
 
 - New Features:
+   - new interpolation feature for config readers - `%(known/parameter)s`.
+     (means last known option with name `parameter`).
    - new options for jail introduced addfailregex/addignoreregex: extends regex 
      specified in filter (opposite to failregex/ignoreregex that overwrites it)
      see gh-867.

fail2ban/client/configparserinc.py

@@ -226,6 +226,11 @@ after = 1.conf
 						if isinstance(s, dict):
 							s2 = alls.get(n)
 							if isinstance(s2, dict):
+								# save previous known values, for possible using in local interpolations later:
+								for k, v in s2.iteritems():
+									if not k.startswith('known/'):
+										s2['known/'+k] = v
+								# merge section
 								s2.update(s)
 							else:
 								alls[n] = s.copy()

fail2ban/tests/clientreadertestcase.py

@@ -436,6 +436,11 @@ class JailsReaderTest(LogCaptureTestCase):
 			 ['set', 'test2failregex', 'addfailregex', 'failure 1 <IP>'], 
 			 ['set', 'test2failregex', 'addfailregex', 'failure 2 <IP>'],
 			 ['start', 'test2failregex'],
+			 ['add', 'test3known-interp', 'auto'],
+			 ['set', 'test3known-interp', 'addfailregex', 'failure test 1 (filter.d/test.conf) <HOST>'],
+			 ['set', 'test3known-interp', 'addfailregex', 'failure test 2 (filter.d/test.local) <HOST>'],
+			 ['set', 'test3known-interp', 'addfailregex', 'failure test 3 (jail.local) <HOST>'],
+			 ['start', 'test3known-interp'],
 			 ['add', 'missinglogfiles', 'auto'],
 			 ['set', 'missinglogfiles', 'addfailregex', '<IP>'],
 			 ['add', 'brokenaction', 'auto'],

fail2ban/tests/config/filter.d/test.conf

@@ -0,0 +1,6 @@
+#[INCLUDES]
+#before = common.conf
+
+[Definition]
+failregex = failure test 1 (filter.d/test.conf) <HOST>
+

fail2ban/tests/config/filter.d/test.local

@@ -0,0 +1,7 @@
+#[INCLUDES]
+#before = common.conf
+
+[Definition]
+failregex = %(known/failregex)s
+            failure test 2 (filter.d/test.local) <HOST>
+

fail2ban/tests/config/jail.conf

@@ -27,6 +27,11 @@ filter = simple
 failregex = failure 1 <IP>
             failure 2 <IP>
 
+[test3known-interp]
+enabled = true
+filter = test
+addfailregex = failure test 3 (jail.local) <HOST>
+
 [missinglogfiles]
 enabled = true
 logpath = /weapons/of/mass/destruction