move container generation to its own file

Signed-off-by: ahuston-0 <aliceghuston@gmail.com>

lib/container-utils.nix

@@ -0,0 +1,43 @@
+{ lib, ... }:
+
+{
+  # Given a attrset of images and a function which generates an image spec,
+  # generates a set of containers (although this could in theory be used for
+  # other things... I'd like to see people try)
+  #
+  # container set must be in the below format
+  # { container-name = {image = "image-uri"; scale = n;}; }
+  # where image-uri gets passed in to the container-spec function as a custom
+  # parameter, and scale is an integer that generates the containers
+  #
+  # container-spec must be a function which accepts two parameter (the
+  # container name and image name) and ideally returns an oci-compliant
+  # container.
+  #
+  # args:
+  # containers: an AttrSet which specifies the imageUri and scale of each
+  #   container
+  # container-spec: a function which produces an oci-compliant container spec
+  #
+  # type:
+  # AttrSet -> (String -> AttrSet -> AttrSet) -> AttrSet
+  createTemplatedContainers =
+    containers: container-spec:
+    builtins.listToAttrs (
+      lib.flatten (
+        lib.mapAttrsToList (
+          name: value:
+          (map (
+            num:
+            let
+              container-name = "${name}-${toString num}";
+            in
+            {
+              name = container-name;
+              value = container-spec container-name value.image;
+            }
+          ) (lib.lists.range 1 value.scale))
+        ) containers
+      )
+    );
+}

lib/default.nix

@@ -3,6 +3,7 @@
   # create rad-dev namespace for lib
   rad-dev = rec {
     systems = import ./systems.nix { inherit lib; };
+    container-utils = import ./container-utils.nix { inherit lib; };
 
     # any(), but checks if any value in the list is true
     #
@@ -57,76 +58,5 @@
     # fileList :: Path -> String -> [Path]
     fileList = dir: map (file: dir + "/${file}") (ls dir);
 
-    # Given a attrset of images and a function which generates an image spec,
-    # generates a set of containers (although this could in theory be used for
-    # other things... I'd like to see people try)
-    #
-    # container set must be in the below format
-    # { container-name = {image = "image-uri"; scale = n;}; }
-    # where image-uri gets passed in to the container-spec function as a custom
-    # parameter, and scale is an integer that generates the containers
-    #
-    # container-spec must be a function which accepts two parameter (the
-    # container name and image name) and ideally returns an oci-compliant
-    # container.
-    #
-    # args:
-    # containers: an AttrSet which specifies the imageUri and scale of each
-    #   container
-    # container-spec: a function which produces an oci-compliant container spec
-    #
-    # type:
-    # AttrSet -> (String -> AttrSet -> AttrSet) -> AttrSet
-    createTemplatedContainers =
-      containers: container-spec:
-      builtins.listToAttrs (
-        lib.flatten (
-          lib.mapAttrsToList (
-            name: value:
-            (map (
-              num:
-              let
-                container-name = "${name}-${toString num}";
-              in
-              {
-                name = container-name;
-                value = container-spec container-name value.image;
-              }
-            ) (lib.lists.range 1 value.scale))
-          ) containers
-        )
-      );
-
-    # Converts an integer into a string
-    #
-    # Given that trying to do this the way you'd do it in languages like python
-    # ("str" + int) causes the program to error out, I assume this is some sort
-    # of cardinal sin of nix. However, I want templated docker containers so
-    # here we are.
-    #
-    # Fun fact: if you want to parse a negative number (I know, scary right?),
-    # you first need to surround it in parentheses (ie. parseInt (-1000)) as nix
-    # interprets negative numbers as a function and will think you're trying to
-    # do some really weird function application magic if you try to call this
-    # normally (ie. parseInt -1000).
-    #
-    # args:
-    # num: an integer to convert
-    #
-    # type:
-    # parseInt :: Integer -> String
-    parseInt =
-      num:
-      let
-        digits = "0123456789";
-        mod = num: (lib.trivial.mod num 10);
-      in
-      if num > 9 then
-        ((parseInt (builtins.div num 10)) + (lib.substring (mod num) 1 digits))
-      else if num < 0 then
-        "-" + (parseInt (builtins.mul num (-1)))
-      else
-        lib.substring (mod num) 1 digits;
   };
-
 }