From e0e7531f7dee948eefb7b8af925c6cd26411c70a Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Tue, 25 May 2021 19:28:08 +0200
Subject: [PATCH] Add image.enableRecommendedContents for /bin/sh and such

---
 docs/modules/ROOT/partials/NixOSOptions.adoc  | 19 ++++++++++
 examples/minimal/arion-compose.nix            |  1 +
 src/nix/modules/service/all-modules.nix       |  1 +
 src/nix/modules/service/image-recommended.nix | 36 +++++++++++++++++++
 4 files changed, 57 insertions(+)
 create mode 100644 src/nix/modules/service/image-recommended.nix

diff --git a/docs/modules/ROOT/partials/NixOSOptions.adoc b/docs/modules/ROOT/partials/NixOSOptions.adoc
index 7709010..63f83d6 100644
--- a/docs/modules/ROOT/partials/NixOSOptions.adoc
+++ b/docs/modules/ROOT/partials/NixOSOptions.adoc
@@ -197,6 +197,25 @@ Default::
 ----
 
 
+No Example:: {blank}
+
+== services.<name>.image.enableRecommendedContents
+
+Add the `/bin/sh` and `/usr/bin/env` symlinks and some lightweight
+files.
+
+
+[discrete]
+=== details
+
+Type:: boolean
+Default::
++
+----
+false
+----
+
+
 No Example:: {blank}
 
 == services.<name>.image.name
diff --git a/examples/minimal/arion-compose.nix b/examples/minimal/arion-compose.nix
index 9531a9f..54a593a 100644
--- a/examples/minimal/arion-compose.nix
+++ b/examples/minimal/arion-compose.nix
@@ -4,6 +4,7 @@
   config.services = {
 
     webserver = {
+      image.enableRecommendedContents = true;
       service.useHostStore = true;
       service.command = [ "sh" "-c" ''
                   cd "$$WEB_ROOT"
diff --git a/src/nix/modules/service/all-modules.nix b/src/nix/modules/service/all-modules.nix
index 18c0432..085f1aa 100644
--- a/src/nix/modules/service/all-modules.nix
+++ b/src/nix/modules/service/all-modules.nix
@@ -5,6 +5,7 @@
   ./host-store.nix
   ./context.nix
   ./image.nix
+  ./image-recommended.nix
   ./nixos.nix
   ./nixos-init.nix
   ../lib/assert.nix
diff --git a/src/nix/modules/service/image-recommended.nix b/src/nix/modules/service/image-recommended.nix
new file mode 100644
index 0000000..a4c5eac
--- /dev/null
+++ b/src/nix/modules/service/image-recommended.nix
@@ -0,0 +1,36 @@
+{ config, lib, pkgs, ... }:
+let
+  inherit (lib)
+    mkIf
+    mkOption
+    types
+    ;
+  inherit (types)
+    bool
+    ;
+
+  recommendedContents = { runCommand, bash, coreutils }:
+    runCommand "recommended-contents" {} ''
+      mkdir -p $out/bin $out/usr/bin $out/var/empty
+      ln -s ${bash}/bin/sh $out/bin/sh
+      ln -s ${coreutils}/bin/env $out/usr/bin/env
+    '';
+in
+{
+  options = {
+    image.enableRecommendedContents = mkOption {
+      type = bool;
+      default = false;
+      description = ''
+        Add the `/bin/sh` and `/usr/bin/env` symlinks and some lightweight
+        files.
+      '';
+    };
+  };
+
+  config = {
+    image.contents = mkIf config.image.enableRecommendedContents [
+      (pkgs.callPackage recommendedContents {})
+    ];
+  };
+}