ci-runner experiment

modules/ci-runner/default.nix

@@ -1,8 +1,15 @@
-{ lib, config, pkgs, self, ... }:
+{ lib, config, pkgs, self, dockerTools, ... }:
 
 with lib;
 let
-  bootstrap = pkgs.writeScript "bootstrap.sh" ''
+  runnerImageName = "ci-runner-docker-drone-exec";
+  runnerImage = dockerTools.buildImage {
+    name = runnerImageName;
+    tag = "latest";
+
+    fromImageName = "debian";
+
+    runAsRoot = ''
       #!/usr/bin/env bash
 
       set -e
@@ -10,7 +17,7 @@ let
       apt update
       apt install --yes curl git sudo xz-utils
 
-    adduser --system --uid 999 build
+      adduser --system --uid 9999 build
       chown build /nix
 
       sudo -u build curl -L https://nixos.org/nix/install > install
@@ -28,6 +35,11 @@ let
 
       curl -L https://github.com/drone-runners/drone-runner-exec/releases/latest/download/drone_runner_exec_linux_amd64.tar.gz | tar xz
       sudo install -t /usr/local/bin drone-runner-exec
+    '';
+  };
+
+  startup = pkgs.writeScript "startup.sh" ''
+    chown build /nix
 
     if [ ! -f /run/vars ]; then
       exit 1
@@ -38,6 +50,7 @@ let
 
     su - -s /bin/bash build sh -c "/usr/local/bin/drone-runner-exec daemon /run/runtime-vars"
   '';
+
   psCfg = config.pub-solar;
   cfg = config.pub-solar.ci-runner;
 in
@@ -62,7 +75,7 @@ in
 
     runnerEnvironment = lib.mkOption {
       description = ''
-        Additional environment vars added to the vars file on container runtime
+        Additional environment variables added to the vars file on container runtime
       '';
       default = {};
     };
@@ -84,15 +97,16 @@ in
       oci-containers = {
         backend = "docker";
         containers."drone-exec-runner" = {
-          image = "debian";
+          image = runnerImageName;
+          imageFile = runnerImage;
           autoStart = true;
           entrypoint = "bash";
-          cmd = [ "/bootstrap.sh" ];
+          cmd = [ "/startup.sh" ];
 
           volumes = [
             "${cfg.runnerVarsFile}:/run/vars"
             "${cfg.nixCacheLocation}:/nix"
-            "${bootstrap}:/bootstrap.sh"
+            "${startup}:/startup.sh"
           ];
 
           environment = cfg.runnerEnvironment;