--- title: "Monorepo Deploy Script — Subdirectory .git Check Pitfall" aliases: [monorepo-git-pull, deploy-script-monorepo, git-pull-monorepo] tags: [monorepo, git, bash, deploy, devops] sources: - "daily/2026-04-16.md" created: 2026-04-16 updated: 2026-04-16 --- # Monorepo Deploy Script — Subdirectory .git Check Pitfall A deploy script written for a multi-repo setup (separate git repos for backend and frontend) will silently fail to pull new code when the project is converted to a monorepo. The script checks for `.git` in subdirectories that don't exist in a monorepo, never finds them, skips the `git pull`, and exits successfully — leaving the server running old code with no warning. ## Key Points - **Silent failure**: the script exits 0 even though `git pull` never ran — nothing in stdout indicates the problem - The symptom: running `scripts/deploy.sh` reports success, but the server is still running the old version - **Fix**: in a monorepo, `git pull` runs once at the repo root — remove all subdirectory `.git` checks - The warning message (if the script emitted one) is easy to miss in CI/CD output or when tailing logs - Multi-repo scripts often check `backend/.git` and `frontend/.git` to determine if each component needs to be pulled separately ## Details ### The Anti-Pattern ```bash # scripts/deploy.sh — written for multi-repo, broken in monorepo if [ -d "backend/.git" ]; then echo "Pulling backend..." cd backend && git pull && cd .. fi if [ -d "frontend/.git" ]; then echo "Pulling frontend..." cd frontend && git pull && cd .. fi # In a monorepo: neither condition is true → git pull never runs # Script exits 0 anyway → deploy "succeeds" with stale code ``` ### The Fix ```bash # scripts/deploy.sh — monorepo version set -e ROOT_DIR="$(cd "$(dirname "$0")/.." && pwd)" cd "$ROOT_DIR" echo "Pulling latest code..." git pull echo "Rebuilding backend..." cd backend && pip install -r requirements.txt && cd .. echo "Rebuilding frontend..." cd frontend && npm ci && npm run build && cd .. echo "Restarting services..." systemctl restart myapp-backend systemctl reload nginx ``` One `git pull` at the root covers all subdirectories in a monorepo. ### Detecting the Problem If a deploy claims success but the running version doesn't match the expected commit: ```bash # On the server — check what commit is actually running git log -1 --oneline # Compare with what should be deployed git fetch origin main git log -1 --oneline origin/main ``` If they differ after a "successful" deploy, the deploy script didn't actually pull. ### Coexisting Deploy Scripts Repositories that transitioned from multi-repo to monorepo sometimes have two deploy scripts: - `full-deploy.sh` — the original multi-repo script (potentially still working for other components) - `scripts/deploy.sh` — the active script that was incorrectly carried over Always identify which script is actually invoked by the CI/CD system or cron job before modifying. ## Related Concepts - [[wiki/concepts/shell-static-deploy-patterns]] — broader deploy script patterns including cp pitfalls and web server reload - [[wiki/concepts/fastapi-mongodb-role-migration]] — the feature deployed in the same session where this bug was found - [[wiki/architecture/_index]] — Docker Compose deployment patterns used alongside these scripts ## Sources - [[daily/2026-04-16.md]] — `scripts/deploy.sh` in Ford QC web app discovered checking `backend/.git` and `frontend/.git`; monorepo never matched; fixed to `git pull` at root