feat(module): improve ability to run jobs locally

adds the correct PATH and environment variables to run it locally
similar to how it works in CI. Also split up the before_script, script
and after_script with simple echo's inbetween for easier debugging

lib/flakeModule.nix

@@ -165,6 +165,17 @@
         prependToBeforeScript = prepend "before_script";
         appendToAfterScript = append "after_script";
 
+        # filter job's variables to either only those containing store paths
+        # or those that do not
+        filterJobVariables = nix: job:
+          lib.concatMapAttrs (
+            name: value:
+              lib.optionalAttrs ((lib.hasInfix "/nix/store/" value) == nix) {
+                ${name} = value;
+              }
+          )
+          (job.variables or {});
+
         jobs = filterAttrsRec (n: v: v != null) config.ci.jobs;
         rest = filterAttrsRec (n: v: v != null) (builtins.removeAttrs config.ci ["jobs" "config"]);
         # this allows us to nix build this to get all the mentioned dependencies from the binary cache
@@ -173,15 +184,8 @@
         # we can support different architectures between runners (eg. the arch of the initial runner does not matter)
         jobsMappedForDeps =
           mapAttrs (key: job: let
-            variablesWithStorePaths =
+            variablesWithStorePaths = filterJobVariables true job;
-              lib.concatMapAttrs (
+            variableExports = lib.concatLines (
-                name: value:
-                  lib.optionalAttrs (lib.hasInfix "/nix/store/" value) {
-                    ${name} = value;
-                  }
-              )
-              (job.variables or {});
-            variableExports = lib.concatMapStrings (x: "${x}\n") (
               lib.mapAttrsToList (name: value: "export ${name}=\"${value}\"") variablesWithStorePaths
             );
           in {
@@ -194,9 +198,26 @@
           jobs;
         # allows the user to directly run the script
         jobsMappedForScript =
-          mapAttrs (key: job: {
+          mapAttrs (key: job: let
+            variablesWithStorePaths = filterJobVariables false job;
+            variableExports = lib.concatLines (
+              lib.mapAttrsToList (name: value: "export ${name}=\"${value}\"") variablesWithStorePaths
+            );
+          in {
             name = "gitlab-ci-job:${key}";
-            value = pkgs.writeShellScriptBin "gitlab-ci-job:${key}" (lib.strings.concatLines (job.before_script or [] ++ job.script ++ job.after_script or []));
+            value = pkgs.writeShellScriptBin "gitlab-ci-job:${key}" ''
+              # set up deps and environment variables containing store paths
+              . ${jobsMappedForDeps."gitlab-ci-job-deps:${key}"}
+              # normal environment variables
+              ${variableExports}
+              # run before_script, script and after_script
+              echo -e "\e[32mRunning before_script...\e[0m"
+              ${lib.concatLines (job.before_script or [])}
+              echo -e "\e[32mRunning script...\e[0m"
+              ${lib.concatLines job.script}
+              echo -e "\e[32mRunning after_script...\e[0m"
+              ${lib.concatLines (job.after_script or [])}
+            '';
           })
           jobs;
         # build the deps specific for this job before anything, this way the deps should be fetched from the cache
@@ -215,11 +236,7 @@
                 // lib.optionalAttrs job.nix.enable {
                   image = job.image;
                   variables =
-                    lib.concatMapAttrs (name: value:
+                    (filterJobVariables false job)
-                      lib.optionalAttrs (!lib.hasInfix "/nix/store/" value) {
-                        ${name} = value;
-                      })
-                    (job.variables or {})
                     // lib.optionalAttrs job.nix.disable-cache {
                       NIX_CI_DISABLE_CACHE = "yes";
                     };