From f9ec52dedceb3904b49c27d49076a881c43ba4cf Mon Sep 17 00:00:00 2001
From: Valentin Shirokov <regellosigkeitsaxiom@yandex.ru>
Date: Tue, 4 Jul 2017 01:58:48 +0300
Subject: [PATCH] Added networking.extraLocalHosts option

It adds its contents to '127.0.0.1' line of /etc/hosts
It makes possible to point multiple domains to localhost in correct way
---
 nixos/modules/config/networking.nix | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/nixos/modules/config/networking.nix b/nixos/modules/config/networking.nix
index d503f5a8b20..ea9e8b712c6 100644
--- a/nixos/modules/config/networking.nix
+++ b/nixos/modules/config/networking.nix
@@ -20,12 +20,24 @@ in
 
   options = {
 
+    networking.extraLocalHosts = lib.mkOption {
+      type = types.listOf types.str;
+      default = [];
+      example = [ "localhost.localdomain" "workinprogress.example.com" ];
+      description = ''
+        Additional entries to be appended to 127.0.0.1 entry in <filename>/etc/hosts</filename>.
+      '';
+    };
+
+
     networking.extraHosts = lib.mkOption {
       type = types.lines;
       default = "";
       example = "192.168.0.1 lanlocalhost";
       description = ''
         Additional entries to be appended to <filename>/etc/hosts</filename>.
+        Note that entries for 127.0.0.1 will not always work correctly if added from here.
+        They should be added via <literal>networking.extraLocalHosts</literal>.
       '';
     };
 
@@ -187,11 +199,11 @@ in
         "rpc".source = pkgs.glibc.out + "/etc/rpc";
 
         # /etc/hosts: Hostname-to-IP mappings.
-        "hosts".text =
+        "hosts".text = let foo = concatStringsSep " " cfg.extraLocalHosts; in
           ''
-            127.0.0.1 localhost
+            127.0.0.1 localhost ${foo}
             ${optionalString cfg.enableIPv6 ''
-              ::1 localhost
+              ::1 localhost ${foo}
             ''}
             ${cfg.extraHosts}
           '';