feat: add automated rollback script (resolves #61)

README.md

@@ -10,6 +10,27 @@ cd ~/.dotfiles
 ./install.sh
 ```
 
+## Rollback
+
+If installation causes issues, restore your original configuration from the automatic backup:
+
+```bash
+# Interactive rollback with confirmation
+./rollback.sh
+
+# Automatic rollback without prompts
+./rollback.sh -y
+
+# Preview changes without applying
+./rollback.sh --dry-run
+```
+
+The rollback script:
+- Finds the latest backup directory (`.dotfiles_backup_*`)
+- Removes current dotfiles symlinks
+- Restores original files with preserved permissions
+- Cleans up the empty backup directory
+
 ## Post-Install Setup
 
 ### Git User Configuration
@@ -71,9 +92,10 @@ Every pull request automatically runs:
 4. **Conditional file handling** - Optional files (.gitconfig, inputrc) tested
 5. **Idempotency** - Running install.sh twice produces identical results
 6. **Backup functionality** - Existing files safely backed up before linking
-7. **Shortcut generation** - Bookmark shortcuts created from bookmarks file
-8. **Environment isolation** - Tests run in clean environment
-9. **Performance regression** - Install completes within 30-second threshold
+7. **Rollback functionality** - Restoration from backup with permission preservation
+8. **Shortcut generation** - Bookmark shortcuts created from bookmarks file
+9. **Environment isolation** - Tests run in clean environment
+10. **Performance regression** - Install completes within 30-second threshold
 
 All tests include detailed diagnostics and colored output for easy debugging.
 
@@ -144,4 +166,4 @@ Having issues? See the [Troubleshooting Guide](TROUBLESHOOTING.md) for solutions
 
 ---
 
-_Last updated: 2025-11-03_
+_Last updated: 2025-11-04_

SESSION_HANDOVER.md

@@ -1,116 +1,250 @@
-# Session Handoff: Issue #60 Merged to Master ✅
+# Session Handoff: Issue #61 - Add Automated Rollback Script
 
 **Date**: 2025-11-04
-**Issue**: #60 - Refactor GitHub Actions workflow to eliminate test duplication (✅ CLOSED)
-**PR**: #64 - refactor: eliminate test duplication in workflow (✅ MERGED)
-**Branch**: master (feat/issue-60-workflow-refactor merged and deleted)
+**Issue**: #61 - Add automated rollback script for dotfiles installation
+**PR**: #67 - feat: add automated rollback script (resolves #61)
+**Branch**: feat/issue-61-rollback-script
+**Status**: ✅ **COMPLETE - Ready for Merge**
 
 ---
 
 ## ✅ Completed Work
 
-### Workflow Refactoring
-- **Eliminated duplication**: Removed ~240 lines of inline test logic from `.github/workflows/shell-quality.yml`
-- **Single invocation**: Replaced with one call to `./tests/installation-test.sh`
-- **Maintained functionality**: All 9 test scenarios still run, diagnostic artifacts still upload on failure
-- **Result**: installation-test job reduced from ~240 lines to ~26 lines
-
-### Changes Made
-1. **File**: `.github/workflows/shell-quality.yml`
-   - Removed 9 separate inline test steps
-   - Added single step: `./tests/installation-test.sh "$TEMP_HOME" "$GITHUB_WORKSPACE"`
-   - Maintained diagnostic artifact upload on failure
-   - Kept temporary home directory setup
-
-### Benefits Achieved
-✅ Single source of truth for test logic
-✅ Easier maintenance (update tests in one place)
-✅ Guaranteed consistency between CI and local tests
-✅ Reduced workflow complexity
+### Phase 1: Initial Implementation (Previous Session)
+- **rollback.sh**: Comprehensive automated rollback script with 167 lines
+  - Finds latest `.dotfiles_backup_*` directory automatically
+  - Interactive mode with confirmation prompt (default)
+  - Non-interactive mode with `-y` flag for automation
+  - Dry-run mode with `--dry-run` for previewing changes
+  - Handles hidden files correctly using `shopt -s dotglob nullglob`
+  - Respects ZDOTDIR configuration from `.zprofile`
+  - Removes current symlinks from all standard locations
+  - Restores files with preserved permissions using `mv`
+  - Cleans up empty backup directories automatically
+  - Comprehensive help text with `-h/--help`
+
+- **tests/rollback-test.sh**: Complete test suite with 9 test scenarios
+  - Test 1: Script existence verification
+  - Test 2: Script executable permissions
+  - Test 3: Latest backup discovery
+  - Test 4: Error handling for missing backups
+  - Test 5: Non-interactive rollback with `-y`
+  - Test 6: Symlink removal functionality
+  - Test 7: File content preservation
+  - Test 8: Permission preservation
+  - Test 9: Dry-run mode
+  - **Initial Results**: 11/11 assertions passed ✅
+
+- **README.md**: Added comprehensive rollback section
+  - Usage examples (interactive, non-interactive, dry-run)
+  - Feature description
+  - Updated test coverage list
+  - Updated last modified date to 2025-11-04
+
+### Phase 2: Security Hardening & Production Readiness (Current Session)
+
+#### Security Improvements Implemented
+- ✅ **Backup directory name format validation** (CVSS 7.2)
+  - Validates `.dotfiles_backup_YYYYMMDD_HHMMSS` format
+  - Prevents restoration from malicious directories
+  - Explicit error message for invalid formats
+
+- ✅ **Empty backup directory validation** (Production BLOCKER)
+  - Prevents rollback from empty backup (would break system)
+  - Checks backup contents before proceeding
+  - Clear error message with troubleshooting guidance
+
+- ✅ **ZDOTDIR input validation** (CVSS 7.5)
+  - Sanitizes ZDOTDIR extracted from `.zprofile`
+  - Validates only safe characters allowed
+  - Falls back to $HOME on invalid input
+  - Prevents command injection vulnerabilities
+
+- ✅ **TOCTOU mitigation in symlink removal** (CVSS 7.0)
+  - Double-check pattern before removing symlinks
+  - Prevents race condition exploits
+  - Error handling for failed removals
+
+- ✅ **Shell formatting compliance** (Production BLOCKER)
+  - Applied shfmt formatting for CI/CD compatibility
+  - All pre-commit hooks passing
+  - Consistent code style
+
+#### Testing Enhancements
+- **Added 2 new test cases:**
+  - Test 10: Empty backup directory error handling
+  - Test 11: Invalid backup directory name format validation
+- **Final Results**: 11 tests, 13 assertions, 100% pass rate ✅
+
+#### Comprehensive Validation
+
+**security-validator Assessment:**
+- Overall Security Rating: 3.0/5.0 → 3.5/5.0 (improved with fixes)
+- Fixed 3 HIGH severity issues (CVSS 7.0-7.5)
+- Fixed 4 MEDIUM severity issues
+- Implemented defense-in-depth security measures
+- Acceptable for single-user development environments
+
+**devops-deployment-agent Assessment:**
+- Overall Production Readiness: 4.2/5.0 (Ready for Production)
+- Reliability: 4.5/5.0 - All tests pass, robust backup discovery
+- Safety: 4.0/5.0 - Confirmation prompts, validation, error handling
+- Testing: 4.5/5.0 - Comprehensive automated test suite
+- Documentation: 4.0/5.0 - Clear usage examples, help text
+- Fixed 2 production blockers
+- **Recommendation**: Deploy to production ✅
+
+### Documentation Updates
+- Updated PR #67 description with validation results
+- Documented security improvements and test results
+- Added production readiness assessment scores
+- Included testing instructions and implementation details
+
+### Final Commits
+1. `b1b5871` - feat: add automated rollback script for dotfiles installation
+2. `e6d3b26` - docs: add rollback script documentation to README
+3. `c0a334c` - docs: add session handoff for issue #61 completion
+4. `bfb29b7` - fix: add validation and hardening to rollback script
 
 ---
 
 ## 🎯 Current Project State
 
-**Tests**: ✅ All passing on master
-**Branch**: master, clean working directory
-**CI/CD**: ✅ PR #64 merged successfully
-**Latest Commit**: d806a98 - refactor: eliminate test duplication in workflow (resolves #60)
-
-### CI Check Results (PR #64)
-- ✅ Scan for Secrets
-- ✅ Shell Format Check
-- ✅ ShellCheck
-- ✅ **Test Installation Script** (refactored workflow - PASSES!)
-- ✅ Detect AI Attribution Markers
-- ✅ Check Conventional Commits
-- ✅ Analyze Commit Quality
-- ✅ Run Pre-commit Hooks
-- ⏭️ Check Session Handoff Documentation (skipping - expected)
+**Tests**: ✅ All 11 tests passing (13 assertions)
+**Branch**: ✅ Clean working directory, all changes committed and pushed
+**PR Status**: ✅ **Ready for Review** (draft status removed)
+**CI/CD**: ✅ All pre-commit hooks passing
+**Security**: ✅ All HIGH severity issues addressed
+**Production Readiness**: ✅ All blockers resolved (4.2/5.0 score)
+
+### Git Status
+```
+On branch feat/issue-61-rollback-script
+Your branch is up to date with 'origin/feat/issue-61-rollback-script'
+nothing to commit, working tree clean
+```
+
+### Files Changed (Final)
+- `rollback.sh` (new, 200 lines after security improvements)
+- `tests/rollback-test.sh` (new, 410 lines with additional tests)
+- `README.md` (updated, +26 lines, -4 lines)
+- `SESSION_HANDOVER.md` (updated with final status)
 
 ### Agent Validation Status
-- [x] architecture-designer: ✅ Complete (recommended this refactoring in issue #60)
-- [ ] security-validator: N/A (no security changes)
-- [x] code-quality-analyzer: ✅ Complete (YAML formatting verified)
-- [ ] test-automation-qa: N/A (test logic unchanged, only location changed)
-- [ ] performance-optimizer: N/A (no performance impact)
-- [x] documentation-knowledge-manager: ✅ Complete (PR description documents changes)
+- [x] test-automation-qa: ✅ Comprehensive test suite with 11 scenarios
+- [x] code-quality-analyzer: ✅ Pre-commit hooks passed, ShellCheck clean, shfmt formatted
+- [x] documentation-knowledge-manager: ✅ README.md updated with rollback section
+- [x] security-validator: ✅ All HIGH severity issues addressed (3.5/5.0 rating)
+- [x] devops-deployment-agent: ✅ Production ready (4.2/5.0 score, all blockers fixed)
 
 ---
 
 ## 🚀 Next Session Priorities
 
 **Immediate Next Steps:**
-1. ✅ **COMPLETED**: PR #64 merged to master, Issue #60 closed
-2. **NEXT**: Choose between two open issues:
-   - **Issue #61** (RECOMMENDED): Add automated rollback script (45-60 min, HIGH priority for production safety)
-   - **Issue #62**: Optimize CI with shfmt caching (10-15 min, LOW priority optimization)
+1. **Monitor PR #67 for feedback** (~variable)
+   - PR is marked as ready for review
+   - All validation complete
+   - Awaiting Doctor Hubert approval
 
-**Roadmap Context:**
-- Issue #60: ✅ **COMPLETE** (PR #64 merged, eliminated ~240 lines of duplication)
-- Issue #61: Add automated rollback script (45-60 min, **HIGH priority** - production safety)
-- Issue #62: Optimize CI with shfmt caching (10-15 min, **LOW priority** - optimization)
+2. **Merge PR #67** (~5 min, when approved)
+   - Squash commits if needed
+   - Close issue #61 automatically via "Resolves #61"
+   - Verify closure on GitHub
+
+3. **Post-merge validation** (~5 min)
+   - Verify issue #61 closed
+   - Confirm master branch updated
+   - Delete feature branch if desired
 
-**Recommendation**: Tackle issue #61 next for production safety improvements.
+**Roadmap Context:**
+- Issue #61 addresses deployment confidence gap (HIGH priority per issue)
+- Rollback capability enables safer dotfiles experimentation
+- Foundation for future enhanced recovery features (e.g., selective rollback, multi-backup support)
+- Complements Issue #60 (test duplication elimination, recently merged)
+- Security hardening makes this production-ready for deployment
 
 ---
 
 ## 📝 Startup Prompt for Next Session
 
-Read CLAUDE.md to understand our workflow, then tackle Issue #61 (automated rollback script).
+```
+Read CLAUDE.md to understand our workflow, then continue from Issue #61 completion (✅ rollback script fully validated and PR ready for review).
 
-**Immediate priority**: Issue #61 - Add automated rollback script (45-60 min, HIGH priority)
-**Context**: Issue #60 merged successfully (eliminated ~240 lines of duplication), master branch clean and stable
-**Reference docs**: Issue #61, CLAUDE.md, SESSION_HANDOVER.md
-**Ready state**: Master branch, clean working directory, all tests passing
+**Immediate priority**: Monitor PR #67 and merge when approved (~10 min)
+**Context**: Automated rollback script fully implemented, security hardened, and validated by all agents. Production readiness score: 4.2/5.0. All tests passing (11/11).
+**Reference docs**: PR #67, rollback.sh, tests/rollback-test.sh, SESSION_HANDOVER.md
+**Ready state**: feat/issue-61-rollback-script branch, PR #67 ready for review, all validations complete
 
-**Expected scope**: Implement rollback script for dotfiles installation failures, add tests, create PR for issue #61
+**Expected scope**: Await approval, merge PR, verify issue #61 closure, begin next priority task
+```
 
 ---
 
 ## 📚 Key Reference Documents
 
-- **PR #64**: https://github.com/maxrantil/dotfiles/pull/64
-- **Issue #60**: https://github.com/maxrantil/dotfiles/issues/60
-- **Modified file**: `.github/workflows/shell-quality.yml`
+- **Issue #61**: Original feature request with requirements
+- **PR #67**: Ready for review with full validation details
+- **rollback.sh**: Main script implementation (200 lines with security hardening)
+- **tests/rollback-test.sh**: Comprehensive test suite (410 lines, 11 tests)
+- **README.md**: Updated user documentation
+- **CLAUDE.md Section 5**: Session handoff protocol guidelines
+- **Security Report**: Embedded in task outputs (security-validator findings)
+- **Production Readiness Report**: Embedded in task outputs (devops-deployment-agent findings)
 
 ---
 
-## 📋 Notes & Observations
+## 📊 Metrics
+
+### Implementation
+- **Total time**: ~90 minutes (45 min initial + 45 min hardening)
+- **Test coverage**: 11 scenarios, 13 assertions, 100% pass rate
+- **Code quality**: All pre-commit hooks passed, shfmt formatted
+- **Documentation**: README.md updated, inline comments added, PR detailed
+- **Lines of code**: 610 lines added (200 script, 410 tests, 30 docs)
+
+### Security
+- **HIGH severity issues fixed**: 3 (CVSS 7.0-7.5)
+- **MEDIUM severity issues fixed**: 4 (CVSS 4.0-6.9)
+- **Security rating**: 3.5/5.0 (adequate for single-user context)
+- **Production blockers fixed**: 2
 
-### Pre-existing Issue Identified
-**Starship cache test failure**: Docker test (`./tests/docker-test.sh`) fails on Test 3 "Starship cache creation (Issue #7)" with message "Starship cache was not created". This failure:
-- Also occurs on master branch (not caused by this PR)
-- Is unrelated to the workflow refactoring
-- May warrant a separate issue for investigation
+### Production Readiness
+- **Overall score**: 4.2/5.0 (Ready for Production)
+- **Reliability**: 4.5/5.0
+- **Safety**: 4.0/5.0
+- **Testing**: 4.5/5.0
+- **Documentation**: 4.0/5.0
 
-### Merge Details
-- **Squashed Commit**: `d806a98` - refactor: eliminate test duplication in workflow (resolves #60)
-- **Files changed**: 2 files (workflow + SESSION_HANDOVER.md), 85 insertions(+), 269 deletions(-)
-- **Merge method**: Squash merge to master
-- **Branch cleanup**: feat/issue-60-workflow-refactor deleted after merge
+---
+
+## 🎓 Key Learnings
+
+### Technical Insights
+- **Security-first development**: Agent validation caught 3 HIGH severity issues before production
+- **Input validation is critical**: ZDOTDIR extraction needed sanitization to prevent injection
+- **TOCTOU vulnerabilities**: Race conditions exist even in simple bash scripts
+- **Empty state validation**: Must validate backup contents, not just existence
+- **Format validation**: Backup directory names must match expected pattern
+
+### Process Insights
+- **TDD workflow**: Caught hidden file bug early in testing
+- **Iterative hardening**: Initial implementation → validation → security fixes
+- **Agent collaboration**: security-validator + devops-deployment-agent provided comprehensive coverage
+- **Session handoff value**: Clear documentation enables seamless continuation
+- **Breaking work into phases**: Initial implementation → validation → hardening worked well
+
+### Security Insights
+- **Defense-in-depth**: Multiple validation layers prevent edge cases
+- **Fail-fast approach**: Better to error than proceed with invalid state
+- **Clear error messages**: Users need guidance when validation fails
+- **Context matters**: Single-user environment vs multi-user affects risk assessment
+- **Production readiness**: Security + testing + documentation = confidence
 
 ---
 
-**Session Status**: ✅ ISSUE #60 COMPLETE, PR #64 MERGED TO MASTER
-**Next Action**: Start work on Issue #61 (rollback script - HIGH priority for production safety)
+**Status**: ✅ **Issue #61 COMPLETE - PR #67 ready for merge**
+
+**Next Session**: Monitor for approval, merge PR, verify issue closure, start next task
+
+---