# Session 0017: Modular Sync/Promote/Rebuild Architecture

**Date:** 2026-02-22
**Status:** Paused (context checkpoint)
**Origin:** MDF Webseiten session 0032

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## Work Done

- [x] Fixed `SL detect_env()` — was returning "seriousletter" instead of the env name; now scans path components for first match after "data"
- [x] Fixed `MDF list_backups()` indentation bug — try block was at same level as for loop, only parsed the last backup file
- [x] Added `promote` config to `registry.yaml` for mdf (rsync), seriousletter (git), ringsaday (git) — each defines promote type, branch mapping, post-pull behavior
- [x] Added `promote` Typer command to SL `sync.py` — git fetch, diff preview, git pull, Dockerfile change detection, container rebuild/restart, health check; only dev→int and int→prod allowed
- [x] Added `cmd_promote` to ops CLI — delegates to project CLI with `--from`/`--to` args
- [x] Added `cmd_rebuild` to ops CLI — starts containers, waits for health, restores latest backup
- [x] Created 4 new FastAPI routers in ops-dashboard:
  - `promote.py` — SSE streaming promote endpoint
  - `sync_data.py` — SSE streaming sync endpoint
  - `registry.py` — exposes project list + environments + promote config as JSON
  - `rebuild.py` — SSE streaming rebuild/disaster-recovery endpoint
- [x] Updated `backups.py` to read project list from registry API instead of hardcoding
- [x] Added "Operations" page to dashboard sidebar with three sections: Promote Code, Sync Data, Rebuild (Disaster Recovery)
- [x] Operations page uses SSE modal with dry-run toggle; project/direction buttons populated dynamically from `/api/registry/`
- [x] Verified all 7 test categories pass

## Key Decisions / Learnings

- All long-running ops commands (promote, sync, rebuild) use SSE streaming — consistent with existing backup/restore pattern. The `stream_ops_host()` helper is the standard interface.
- Registry is the single source of truth for project/environment/promote config. Dashboard reads it dynamically — no hardcoded project names in API routers.
- Promote direction validation lives in the project CLI (`sync.py`), not in the ops CLI or dashboard — keeps enforcement close to the implementation.
- `ops rebuild` is the disaster recovery entry point: bring up containers → wait for healthy → restore latest backup. Simple, composable.
- `detect_env()` path parsing must handle the full `/opt/data/seriousletter/{env}/code/...` structure — scanning for VALID_ENVS after "data" in path components is robust.

## Files Changed

- `/opt/data/seriousletter/{dev,int,prod}/code/scripts/sync/sync.py` — fix `detect_env`, add `promote` command
- `Code/mdf-system/scripts/sync/sync.py` (local + deployed to dev) — fix `list_backups` indentation
- `/opt/infrastructure/servers/hetzner-vps/registry.yaml` — add `promote` config per project
- `/opt/infrastructure/ops` — add `cmd_promote`, `cmd_rebuild`
- `/opt/data/ops-dashboard/app/routers/promote.py` — new SSE promote endpoint
- `/opt/data/ops-dashboard/app/routers/sync_data.py` — new SSE sync endpoint
- `/opt/data/ops-dashboard/app/routers/registry.py` — new registry JSON endpoint
- `/opt/data/ops-dashboard/app/routers/rebuild.py` — new SSE rebuild endpoint
- `/opt/data/ops-dashboard/app/routers/backups.py` — dynamic project list from registry
- `/opt/data/ops-dashboard/app/main.py` — register 4 new routers
- `/opt/data/ops-dashboard/static/js/app.js` — Operations page UI + SSE modal
- `/opt/data/ops-dashboard/static/index.html` — nav link + ops-modal HTML

## Next Steps (at time of pause)

- [ ] Test backup creation from dashboard UI
- [ ] Test full promote dry-run via dashboard (Operations page)
- [ ] Test sync dry-run via dashboard
- [ ] Commit infrastructure and code repo changes on server
- [ ] DNS cutover mdf-system.de → .ch
- [ ] Disaster recovery test (destroy + rebuild SL dev)

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**Tags:** #Session #OpsDashboard #OpsCLI #Promote #Sync #Rebuild #Registry