feat: add gstack-settings-hook for atomic Claude Code hook management

DRY helper for adding/removing SessionStart hooks in ~/.claude/settings.json. Handles missing files, deduplication, malformed JSON, and atomic writes (.tmp + rename) to prevent corruption on crash or disk-full. Part of team-install-mode feature (credit: Jared Friedman). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-05-02 03:35:09 +02:00 · 2026-04-04 21:00:27 -07:00
parent 04b709d91a
commit 9c429d83ae
1 changed files with 82 additions and 0 deletions
@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+# gstack-settings-hook — add/remove SessionStart hooks in Claude Code settings.json
+#
+# Usage:
+#   gstack-settings-hook add <hook-command>     # add SessionStart hook
+#   gstack-settings-hook remove <hook-command>  # remove SessionStart hook
+#
+# Requires: bun (already a gstack hard dependency)
+# Writes atomically: .tmp + rename to prevent corruption on crash/disk-full.
+
+set -euo pipefail
+
+ACTION="${1:-}"
+HOOK_CMD="${2:-}"
+SETTINGS_FILE="${GSTACK_SETTINGS_FILE:-$HOME/.claude/settings.json}"
+
+if [ -z "$ACTION" ] || [ -z "$HOOK_CMD" ]; then
+  echo "Usage: gstack-settings-hook {add|remove} <hook-command>" >&2
+  exit 1
+fi
+
+if ! command -v bun >/dev/null 2>&1; then
+  echo "Error: bun is required but not installed." >&2
+  exit 1
+fi
+
+case "$ACTION" in
+  add)
+    bun -e "
+      const fs = require('fs');
+      const settingsPath = '$SETTINGS_FILE';
+      const hookCmd = $(printf '%s' "$HOOK_CMD" | bun -e "process.stdout.write(JSON.stringify(require('fs').readFileSync('/dev/stdin','utf8')))");
+
+      let settings = {};
+      try { settings = JSON.parse(fs.readFileSync(settingsPath, 'utf8')); } catch {}
+
+      if (!settings.hooks) settings.hooks = {};
+      if (!settings.hooks.SessionStart) settings.hooks.SessionStart = [];
+
+      // Dedup: check if hook command already registered
+      const exists = settings.hooks.SessionStart.some(entry =>
+        entry.hooks && entry.hooks.some(h => h.command && h.command.includes('gstack-session-update'))
+      );
+
+      if (!exists) {
+        settings.hooks.SessionStart.push({
+          hooks: [{ type: 'command', command: hookCmd }]
+        });
+      }
+
+      const tmp = settingsPath + '.tmp';
+      fs.writeFileSync(tmp, JSON.stringify(settings, null, 2) + '\n');
+      fs.renameSync(tmp, settingsPath);
+    " 2>/dev/null
+    ;;
+  remove)
+    [ -f "$SETTINGS_FILE" ] || exit 0
+    bun -e "
+      const fs = require('fs');
+      const settingsPath = '$SETTINGS_FILE';
+
+      let settings = {};
+      try { settings = JSON.parse(fs.readFileSync(settingsPath, 'utf8')); } catch { process.exit(0); }
+
+      if (settings.hooks && settings.hooks.SessionStart) {
+        settings.hooks.SessionStart = settings.hooks.SessionStart.filter(entry =>
+          !(entry.hooks && entry.hooks.some(h => h.command && h.command.includes('gstack-session-update')))
+        );
+        if (settings.hooks.SessionStart.length === 0) delete settings.hooks.SessionStart;
+        if (Object.keys(settings.hooks).length === 0) delete settings.hooks;
+      }
+
+      const tmp = settingsPath + '.tmp';
+      fs.writeFileSync(tmp, JSON.stringify(settings, null, 2) + '\n');
+      fs.renameSync(tmp, settingsPath);
+    " 2>/dev/null
+    ;;
+  *)
+    echo "Unknown action: $ACTION (expected add or remove)" >&2
+    exit 1
+    ;;
+esac