factor out withEnv (#572)

Reviewed-on: fediversity/fediversity#572

deployment/run/default.nix

@@ -15,7 +15,7 @@ let
     str
     submodule
     ;
-  inherit (pkgs.callPackage ../utils.nix { }) toBash withPackages tfApply;
+  inherit (pkgs.callPackage ../utils.nix { }) withPackages withEnv tfApply;
   writeConfig =
     {
       system,
@@ -244,9 +244,7 @@ in
                 pkgs.jq
               ])
               ''
-                env ${
+                env ${withEnv environment} bash ./deployment/run/ssh-single-host/run.sh
-                  toString (lib.mapAttrsToList (k: v: "${k}=\"${toBash v}\"") environment)
-                } bash ./deployment/run/ssh-single-host/run.sh
               '';
         };
       };

deployment/utils.nix

@@ -5,6 +5,15 @@
   ...
 }:
 rec {
+  mapKeys =
+    keyMapper:
+    lib.mapAttrs' (
+      k: value: {
+        name = keyMapper k;
+        inherit value;
+      }
+    );
+
   evalModel =
     module:
     (lib.evalModules {
@@ -51,6 +60,10 @@ rec {
     ];
   };
 
+  filterNull = lib.filterAttrs (_: v: v != null);
+
+  withEnv = environment: toString (lib.mapAttrsToList (k: v: "${k}=\"${toBash v}\"") environment);
+
   tfApply =
     {
       directory,
@@ -62,14 +75,8 @@ rec {
     }:
     let
       env-vars = ''
-        ${
+        ${withEnv (mapKeys (k: "TF_VAR_${k}") (filterNull environment))} \
-          toString (
+        ${withEnv (filterNull httpBackend.value)} \
-            lib.mapAttrsToList (k: v: "TF_VAR_${k}=\"${toBash v}\"") (
-              lib.filterAttrs (_: v: v != null) environment
-            )
-          )
-        } \
-        ${toString (lib.mapAttrsToList (k: v: "${k}=\"${toBash v}\"") httpBackend.value)} \
       '';
       tfPackage = pkgs.callPackage ./run/${directory}/tf.nix { };
       tf-env = pkgs.callPackage ./run/tf-env.nix {