nixpkgs-update: move worker to bash script

hosts/build02/nixpkgs-update.nix

@@ -56,59 +56,7 @@ let
       StandardOutput = "journal";
     };
 
-    script = ''
+    script = builtins.readFile ./worker.bash;
-      mkdir -p "$LOGS_DIRECTORY/~workers/"
-      # This is for public logs at nixpkgs-update-logs.nix-community.org/~workers
-      exec  > >(rotatelogs -eD "$LOGS_DIRECTORY"'/~workers/%Y-%m-%d-${name}.stdout.log' 86400)
-      exec 2> >(rotatelogs -eD "$LOGS_DIRECTORY"'/~workers/%Y-%m-%d-${name}.stderr.log' 86400 >&2)
-
-      socket=/run/nixpkgs-update-supervisor/work.sock
-
-      function run-nixpkgs-update {
-        exit_code=0
-        set -x
-        timeout 6h ${nixpkgs-update-bin} update-batch --pr --outpaths --nixpkgs-review "$attr_path $payload" || exit_code=$?
-        set +x
-        if [ $exit_code -eq 124 ]; then
-          echo "Update was interrupted because it was taking too long."
-        fi
-        msg="DONE $attr_path $exit_code"
-      }
-
-      msg=READY
-      while true; do
-        response=$(echo "$msg" | socat -t5 UNIX-CONNECT:"$socket" - || true)
-        case "$response" in
-          "") # connection error; retry
-            sleep 5
-            ;;
-          NOJOBS)
-            msg=READY
-            sleep 60
-            ;;
-          JOB\ *)
-            read -r attr_path payload <<< "''${response#JOB }"
-            # If one worker is initializing the nixpkgs clone, the other will
-            # try to use the incomplete clone, consuming a bunch of jobs and
-            # throwing them away. So we use a crude locking mechanism to
-            # run only one worker when there isn't a nixpkgs directory yet.
-            # Once the directory exists and this initial lock is released,
-            # multiple workers can run concurrently.
-            lockdir="$XDG_CACHE_HOME/.nixpkgs.lock"
-            if [ ! -e "$XDG_CACHE_HOME/nixpkgs" ] && mkdir "$lockdir"; then
-              trap 'rmdir "$lockdir"' EXIT
-              run-nixpkgs-update
-              rmdir "$lockdir"
-              trap - EXIT
-              continue
-            fi
-            while [ -e "$lockdir" ]; do
-              sleep 10
-            done
-            run-nixpkgs-update
-        esac
-      done
-    '';
   };
 
   mkFetcher = name: cmd: {

hosts/build02/worker.bash

@@ -0,0 +1,51 @@
+mkdir -p "$LOGS_DIRECTORY/~workers/"
+# This is for public logs at nixpkgs-update-logs.nix-community.org/~workers
+exec  > >(rotatelogs -eD "$LOGS_DIRECTORY"'/~workers/%Y-%m-%d-${name}.stdout.log' 86400)
+exec 2> >(rotatelogs -eD "$LOGS_DIRECTORY"'/~workers/%Y-%m-%d-${name}.stderr.log' 86400 >&2)
+
+socket=/run/nixpkgs-update-supervisor/work.sock
+
+function run-nixpkgs-update {
+  exit_code=0
+  set -x
+  timeout 6h ${nixpkgs-update-bin} update-batch --pr --outpaths --nixpkgs-review "$attr_path $payload" || exit_code=$?
+  set +x
+  if [ $exit_code -eq 124 ]; then
+    echo "Update was interrupted because it was taking too long."
+  fi
+  msg="DONE $attr_path $exit_code"
+}
+
+msg=READY
+while true; do
+  response=$(echo "$msg" | socat -t5 UNIX-CONNECT:"$socket" - || true)
+  case "$response" in
+    "") # connection error; retry
+      sleep 5
+      ;;
+    NOJOBS)
+      msg=READY
+      sleep 60
+      ;;
+    JOB\ *)
+      read -r attr_path payload <<< "''${response#JOB }"
+      # If one worker is initializing the nixpkgs clone, the other will
+      # try to use the incomplete clone, consuming a bunch of jobs and
+      # throwing them away. So we use a crude locking mechanism to
+      # run only one worker when there isn't a nixpkgs directory yet.
+      # Once the directory exists and this initial lock is released,
+      # multiple workers can run concurrently.
+      lockdir="$XDG_CACHE_HOME/.nixpkgs.lock"
+      if [ ! -e "$XDG_CACHE_HOME/nixpkgs" ] && mkdir "$lockdir"; then
+        trap 'rmdir "$lockdir"' EXIT
+        run-nixpkgs-update
+        rmdir "$lockdir"
+        trap - EXIT
+        continue
+      fi
+      while [ -e "$lockdir" ]; do
+        sleep 10
+      done
+      run-nixpkgs-update
+  esac
+done