ssh: support using ssh-configured useroptional-ssh-user

Let ssh use the user configured in its configuration files when the
target user is set to the empty string.

Closes https://github.com/krebs/krops/issues/2

1 files changed, 7 insertions, 5 deletions

diff --git a/pkgs/populate/default.nix b/pkgs/populate/default.nix
index 1367a50..f78aa4a 100644
--- a/pkgs/populate/default.nix
+++ b/pkgs/populate/default.nix
@@ -162,8 +162,10 @@ let
         --delete-excluded \
         "$source_path" \
         ${quote (
-          optionalString (!isLocalTarget target)
-                         "${target.user}@${target.host}:" +
+          optionalString (!isLocalTarget target) (
+            (optionalString (target.user != "") "${target.user}@") +
+            "${target.host}:"
+          ) +
           target.path
         )} \
       >&2
@@ -176,13 +178,13 @@ let
         ${ssh' target} ${quote target.host} ${quote script}
       '';
 
-  ssh' = target: concatMapStringsSep " " quote [
+  ssh' = target: concatMapStringsSep " " quote (flatten [
     "${openssh}/bin/ssh"
-    "-l" target.user
+    (optionals (target.user != "") ["-l" target.user])
     "-o" "ControlPersist=no"
     "-p" target.port
     "-T"
-  ];
+  ]);
 
 in