From f4c0df84eeccbf27c0a3937cbd2aabff0a2420bd Mon Sep 17 00:00:00 2001
From: Joey Hess <joey@kitenet.net>
Date: Sat, 19 Apr 2014 01:55:32 -0400
Subject: [PATCH] secondaryFor

---
 Propellor/Property/Dns.hs | 20 +++++++++++++++++---
 config-joey.hs            | 14 +++++++-------
 2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/Propellor/Property/Dns.hs b/Propellor/Property/Dns.hs
index 4c93799..68ce757 100644
--- a/Propellor/Property/Dns.hs
+++ b/Propellor/Property/Dns.hs
@@ -2,6 +2,7 @@ module Propellor.Property.Dns (
 	module Propellor.Types.Dns,
 	primary,
 	secondary,
+	secondaryFor,
 	mkSOA,
 	rootAddressesFrom,
 	writeZoneFile,
@@ -71,10 +72,23 @@ primary hosts domain soa rs = withwarnings (check needupdate baseprop)
 
 -- | Secondary dns server for a domain.
 --
+-- The primary server is determined by looking at the properties of other
+-- hosts to find which one is configured as the primary.
+--
 -- Note that if a host is declared to be a primary and a secondary dns
 -- server for the same domain, the primary server config always wins.
-secondary :: [Host] -> Domain -> HostName -> Property
-secondary hosts domain master = pureAttrProperty desc (addNamedConf conf)
+secondary :: [Host] -> Domain -> Property
+secondary hosts domain = secondaryFor masters hosts domain
+  where
+	masters = M.keys $ M.filter ismaster $ hostAttrMap hosts
+	ismaster attr = case M.lookup domain (_namedconf attr) of
+		Nothing -> False
+		Just conf -> confType conf == Master && confDomain conf == domain
+
+-- | This variant is useful if the primary server does not have its DNS
+-- configured via propellor.
+secondaryFor :: [HostName] -> [Host] -> Domain -> -> Property
+secondaryFor masters hosts domain = pureAttrProperty desc (addNamedConf conf)
 	`requires` servingZones
   where
  	desc = "dns secondary for " ++ domain
@@ -82,7 +96,7 @@ secondary hosts domain master = pureAttrProperty desc (addNamedConf conf)
 		{ confDomain = domain
 		, confType = Secondary
 		, confFile = "db." ++ domain
-		, confMasters = hostAddresses master hosts
+		, confMasters = concatMap (\m -> hostAddresses m hosts) masters
 		, confLines = ["allow-transfer { }"]
 		}
 
diff --git a/config-joey.hs b/config-joey.hs
index 7fadd8b..a130612 100644
--- a/config-joey.hs
+++ b/config-joey.hs
@@ -246,15 +246,15 @@ cleanCloudAtCost = propertyList "cloudatcost cleanup"
 
 myDnsSecondary :: Property
 myDnsSecondary = propertyList "dns secondary for all my domains"
-	[ Dns.secondary hosts "kitenet.net" master
-	, Dns.secondary hosts "joeyh.name" master
-	, Dns.secondary hosts "ikiwiki.info" master
-	, Dns.secondary hosts "olduse.net" master
-	, Dns.secondary hosts "branchable.com" branchablemaster
+	[ Dns.secondaryFor wren hosts "kitenet.net"
+	, Dns.secondaryFor wren hosts "joeyh.name"
+	, Dns.secondaryFor wren hosts "ikiwiki.info"
+	, Dns.secondary hosts "olduse.net"
+	, Dns.secondaryFor branchable hosts "branchable.com"
 	]
   where
-	master = "wren.kitenet.net"
-	branchablemaster = "branchable.com"
+	wren = ["wren.kitenet.net"]
+	branchable = ["branchable.com"]
 
 main :: IO ()
 main = defaultMain hosts