From 8180922d236c53b5e09cfe1b63f6c12977bb2803 Mon Sep 17 00:00:00 2001
From: Joachim Fasting <joachifm@fastmail.fm>
Date: Tue, 25 Oct 2016 20:56:54 +0200
Subject: cjdns service: refactor cjdns hosts builder

The old version would export two lists to a bash builder and do pairwise
processing on the bash side.  In the new version we instead generate a
logic free builder on the Nix side. This is not only conceptually
simpler but reduces the amount of code and intermediate values.
---
 nixos/modules/services/networking/cjdns-hosts.sh | 11 ---------
 nixos/modules/services/networking/cjdns.nix      | 29 +++++++++++-------------
 2 files changed, 13 insertions(+), 27 deletions(-)
 delete mode 100644 nixos/modules/services/networking/cjdns-hosts.sh

(limited to 'nixos/modules/services')

diff --git a/nixos/modules/services/networking/cjdns-hosts.sh b/nixos/modules/services/networking/cjdns-hosts.sh
deleted file mode 100644
index 8a2b47e52143..000000000000
--- a/nixos/modules/services/networking/cjdns-hosts.sh
+++ /dev/null
@@ -1,11 +0,0 @@
-pubs=($pubs)
-hosts=($hosts)
-
-lines="''\n"
-for ((i = 0; i < ${#pubs[*]}; i++)); do
-    addr=$($cjdns/bin/publictoip6 ${pubs[i]})
-    lines="${lines}$addr ${hosts[i]}\n"
-done
-lines="${lines}''"
-
-echo -ne $lines > $out
diff --git a/nixos/modules/services/networking/cjdns.nix b/nixos/modules/services/networking/cjdns.nix
index 849d273a41d3..5e15e40ea0c1 100644
--- a/nixos/modules/services/networking/cjdns.nix
+++ b/nixos/modules/services/networking/cjdns.nix
@@ -28,21 +28,18 @@ let
     };
   };
 
-  peers = mapAttrsToList (n: v: v) (cfg.ETHInterface.connectTo // cfg.UDPInterface.connectTo);
-
-  pubs  = toString (map (p: if p.hostname == "" then "" else p.publicKey) peers);
-  hosts = toString (map (p: if p.hostname == "" then "" else p.hostname)  peers);
-
-  cjdnsHosts =
-    if hosts != "" then
-      import (pkgs.stdenv.mkDerivation {
-        name = "cjdns-hosts";
-        builder = ./cjdns-hosts.sh;
-
-        inherit (pkgs) cjdns;
-        inherit pubs hosts;
-      })
-    else "";
+  # Additional /etc/hosts entries for peers with an associated hostname
+  cjdnsExtraHosts = import (pkgs.runCommand "cjdns-hosts" {}
+    # Generate a builder that produces an output usable as a Nix string value
+    ''
+      exec >$out
+      echo \'\'
+      ${concatStringsSep "\n" (mapAttrsToList (k: v:
+          optionalString (v.hostname != "")
+            "echo $(${pkgs.cjdns}/bin/publictoip6 ${x.key}) ${x.host}")
+          (cfg.ETHInterface.connectTo // cfg.UDPInterface.connectTo))}
+      echo \'\'
+    '');
 
   parseModules = x:
     x // { connectTo = mapAttrs (name: value: { inherit (value) password publicKey; }) x.connectTo; };
@@ -254,7 +251,7 @@ in
       };
     };
 
-    networking.extraHosts = "${cjdnsHosts}";
+    networking.extraHosts = cjdnsExtraHosts;
 
     assertions = [
       { assertion = ( cfg.ETHInterface.bind != "" || cfg.UDPInterface.bind != "" || cfg.confFile != null );
-- 
cgit 1.4.1