Close out issue 001: document CSRF/reverse-proxy requirement

The app-side fix (CSRF_TRUSTED_ORIGINS, SECURE_PROXY_SSL_HEADER in
settings.py) was already committed as d458cd3 after the first Cloud-VM-1
deployment hit "CSRF verification failed" on login behind Apache. This
finishes the rest of that issue's checklist: documents
DJANGO_CSRF_TRUSTED_ORIGINS in deploy/env.example, adds the required
X-Forwarded-Proto header to the Apache/Caddy examples in
cloud_agent_deploy.md (plus a checklist item that verifies via an actual
login, not just an unauthenticated capabilities curl), and adds the same
proxy-agnostic guidance to docs/deployment.md.

Also introduces issues/, a tracked one-file-per-issue log for the project
going forward.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
This commit is contained in:
peter 2026-09-02 12:28:41 +01:00
parent d458cd3673
commit f2f2a9c96b
5 changed files with 114 additions and 3 deletions

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# 001 — CSRF verification fails behind a TLS-terminating reverse proxy
**Status:** Fixed
## Description
Deploying Daybook behind Apache (TLS-terminating reverse proxy → plain HTTP
to the container) on `cloud-vm-1`, login failed with:
```
Forbidden (403)
CSRF verification failed. Request aborted.
```
**Root cause:** `daybook_project/settings.py` set `ALLOWED_HOSTS` from an env
var but never set `CSRF_TRUSTED_ORIGINS` or `SECURE_PROXY_SSL_HEADER`. Without
the latter, Django has no way to know the original request was HTTPS — the
proxy terminates TLS and forwards plain HTTP — so it treats every request as
insecure, which breaks CSRF checks on any POST (including login) once a
browser connects over `https://`.
This isn't specific to `cloud-vm-1` — it'll happen on any reverse-proxied
deployment (Apache, Nginx, Traefik, a cloud load balancer), which is the
explicitly recommended setup in `deploy/cloud_agent_deploy.md` §8. The
runbook doesn't mention CSRF or proxy-awareness anywhere.
## Fix
**App (`daybook_project/settings.py`):**
```python
CSRF_TRUSTED_ORIGINS = [origin.strip() for origin in os.environ.get("DJANGO_CSRF_TRUSTED_ORIGINS", "").split(",") if origin.strip()]
SECURE_PROXY_SSL_HEADER = ("HTTP_X_FORWARDED_PROTO", "https")
```
Committed locally as `d458cd3` ("Fix CSRF failure behind a TLS-terminating
reverse proxy") — **needs to be pushed to `main`**, the deploy agent that
made this fix didn't have push access to the Forgejo repo.
**Deploy env (`deploy/env.example` / runbook):** needs a new var,
`DJANGO_CSRF_TRUSTED_ORIGINS`, set to the public HTTPS origin, e.g.:
```
DJANGO_CSRF_TRUSTED_ORIGINS=https://daybook.example.com
```
**Proxy config:** `SECURE_PROXY_SSL_HEADER` only works if the proxy actually
sends that header. The Apache example in `cloud_agent_deploy.md` §8 is
missing it — needs:
```apache
RequestHeader set X-Forwarded-Proto "https"
```
inside the `<VirtualHost *:443>` block (requires `a2enmod headers`). The
equivalent for Nginx is `proxy_set_header X-Forwarded-Proto $scheme;`, worth
adding to `docs/deployment.md`'s reverse-proxy notes too since that doc
mentions Nginx/Traefik as options without this caveat.
## Resolution
- [x] Pushed commit `d458cd3` to `main`.
- [x] Added `DJANGO_CSRF_TRUSTED_ORIGINS` to `deploy/env.example` with an
explanatory comment.
- [x] Updated `cloud_agent_deploy.md` §8's Apache example to include
`RequestHeader set X-Forwarded-Proto "https"`, plus a Caddy equivalent
and a checklist item that verifies by actually logging in through the
proxy (not just curling `/api/capabilities`, which is unauthenticated
GET and wouldn't have caught this).
- [x] Updated `docs/deployment.md`'s "Reverse Proxy Notes" and checklist with
the same requirement, plus an Nginx/Apache/Caddy header cheat sheet.