EventSnap/.env.example

# ── Domain ────────────────────────────────────────────────────────────────────
# Public domain Caddy will serve and obtain a TLS certificate for.
#
# The DNS A record must already point at this server BEFORE the first `up -d`: Caddy
# requests a certificate on boot, and Let's Encrypt allows only 5 failed validations per
# hostname per hour. Never delete the caddy_data volume — it holds the certificate and
# the ACME account key.
DOMAIN=my-event.example.com

# ── Image version ─────────────────────────────────────────────────────────────
# Tag pulled for the `app` and `frontend` services (docker-compose.yml). Production runs
# prebuilt images from the registry and never compiles — see DEPLOYMENT_RUNBOOK.md.
# Always an immutable tag, never `latest`: rollback is `EVENTSNAP_VERSION=<previous>`
# + `docker compose up -d`, which works offline if that image is still resident locally.
#
# ⚠ THIS TAG DOES NOT EXIST YET. The newest git tag is v0.12.0; v0.13.0 is the release you
# cut for the event. Build and push it (plus its identical rollback twin v0.13.0-a) BEFORE
# the first `docker compose up -d` — see DEPLOYMENT_RUNBOOK.md §6 (build) and §9 (rollback).
# Copying this file and starting the stack without that step fails with `manifest unknown`.
#
# Do NOT "fix" this by dropping back to v0.12.0: no image was ever built for it, and a
# 6-migration tree booting against a 31-migration database returns VersionMissing and
# crash-loops forever behind a live Caddy. §9 covers this in full.
EVENTSNAP_VERSION=v0.13.0

# ── App server ────────────────────────────────────────────────────────────────
APP_PORT=3000
# Set to `production` in real deployments. This activates the secret guard that
# refuses to boot with placeholder JWT_SECRET / ADMIN_PASSWORD_HASH values.
# (docker-compose.yml already sets APP_ENV=production for the app service.)
APP_ENV=production

# ── Database ──────────────────────────────────────────────────────────────────
# Set a strong password and keep it in sync between DATABASE_URL and
# POSTGRES_PASSWORD. Generate one with: openssl rand -hex 24
#
# SET THIS BEFORE THE FIRST `docker compose up -d`. Postgres reads POSTGRES_PASSWORD
# only when it initialises its data directory, on that very first boot. Change it
# afterwards and the app authenticates with the new password against a volume still
# holding the old one — a permanent restart loop ("password authentication failed").
# The only ways out are restoring the old password or `docker compose down -v`, which
# deletes the database, the media and the exports. In production the app refuses to
# boot while this is still the placeholder below, so it cannot be missed by accident.
DATABASE_URL=postgres://eventsnap:CHANGE_ME_use_a_strong_password@db:5432/eventsnap
POSTGRES_USER=eventsnap
POSTGRES_PASSWORD=CHANGE_ME_use_a_strong_password
POSTGRES_DB=eventsnap
# Connection pool size. The code default is 15 (DEFAULT_MAX_CONNECTIONS in backend/src/db.rs),
# and docker-compose.yml pins this value in `app.environment` so an edit here cannot reach the
# container. That pin is deliberate: since the value became boot-FATAL when unparseable — so an
# operator tuning a knob that never took effect gets told, instead of silently staying on the
# default — a stray quote or a trailing inline comment in `.env` would crash-loop the app behind
# a live Caddy. Change the pin in compose, not this line.
#
# SIZE IT TO THE CORES, NOT TO THE GUESTS. The earlier advice here was ~30, reasoned from
# "~100 guests polling the feed at once" back when a feed page cost ~449 ms and connections
# were spent waiting. Migration 024 replaced the feed view's GROUP BY with scalar subqueries
# and a page now costs well under a millisecond, so concurrency is no longer where the time
# goes. On a 2 vCPU box 30 simultaneous queries cannot run — they queue on the CPU instead of
# on the pool, which is the same wait wearing a different hat, and 30 Postgres backends plus
# shared_buffers is snug in the 1G that docker-compose.yml allots `db`.
#
# 15 on 2 vCPU / 4 GB. Raise toward 30 only alongside more cores AND a bigger `db` memory
# limit — an OOM in Postgres doesn't degrade one feature, it takes the whole event down.
DATABASE_MAX_CONNECTIONS=15

# Log level: see the "Logging" section near the bottom of this file.
#
# Defined THERE and nowhere else, deliberately. This file used to assign RUST_LOG twice —
# once here and once there — and Compose takes the LAST assignment, so editing this line to
# `debug` to chase a problem during the event changed nothing at all, silently. A key that
# appears twice in a .env is a trap regardless of which value is better.

# ── Authentication ────────────────────────────────────────────────────────────
# Generate with: openssl rand -hex 64
JWT_SECRET=change_me_to_a_random_64_byte_hex_string
SESSION_EXPIRY_DAYS=30

# Admin dashboard password (bcrypt hash).
# Generate with an image the stack already pulls (htpasswd needs apache2-utils, which
# a stock VPS does not have):
#   docker run --rm caddy:2-alpine caddy hash-password --plaintext 'yourpassword'
# IMPORTANT: keep the SINGLE QUOTES. A bcrypt hash is full of `$` (e.g. $2b$12$…$…),
# and both Docker Compose's env_file interpolation and dotenvy's variable substitution
# would otherwise eat the `$…` segments (reading them as unset vars) and corrupt the
# hash — every admin login then 401s. Single quotes make both read it literally.
ADMIN_PASSWORD_HASH='$2y$12$placeholder_replace_me'

# ── Event ─────────────────────────────────────────────────────────────────────
EVENT_NAME=Max & Maria's Wedding
EVENT_SLUG=max-maria-2026

# ── Storage ───────────────────────────────────────────────────────────────────
MEDIA_PATH=/media
# Export archives (Gallery.zip / Memories.zip). MUST be outside MEDIA_PATH —
# /media is publicly served, so exports here would be downloadable without auth.
EXPORT_PATH=/exports

# ── Runtime settings (upload limits, rate limits, capacity) ───────────────────
# NOTE: These are NOT environment variables. Upload size caps, rate limits, guest
# count and quota tolerance are stored in the database `config` table (seeded once
# at first boot) and changed at runtime from the ADMIN DASHBOARD — the backend does
# not read them from .env. Setting them here has no effect. Current seeded defaults:
#   upload rate      100 / hour / guest   (raised from 10 by migration 015)
#   feed rate         60 / minute
#   export rate        3 / day
#   max image size    20 MB
#   max video size   500 MB
#   estimated guests 100
#   quota tolerance  0.75  (see below — NOT a warning threshold)
# Adjust these in the admin UI before the event if needed.
#
# quota_tolerance is the MULTIPLIER IN THE PER-USER QUOTA FORMULA, not the point at
# which anything warns you:
#
#     divisor        = max(active_uploaders, estimated_guest_count, 1)
#     per_user_limit = max(floor(free_disk * quota_tolerance / divisor), 500 MiB)
#
# estimated_guest_count is a FLOOR ON THE DIVISOR, not decoration — it is a live knob
# (upload::quota_limit_bytes). Earlier drafts of this file and the runbook both omitted
# it and told operators it was inert; it is not.
#
# It is recomputed against LIVE free space on every upload, so in principle it self-
# throttles: guests converge on a fixed point at tolerance/(1+tolerance) of the free space
# you started with — 43% at 0.75.
#
# ON THIS BOX THAT FIXED POINT NEVER BINDS, and it is worth knowing which knob actually
# stops the disk filling. The arithmetic above used to be quoted as "~30 GB of a fresh
# 70 GB", which is an 80 GB CX33; this deploys to a CX22 with 40 GB. At ~28 GB free and
# estimated_guest_count = 100 flooring the divisor, the formula yields ~210 MB per guest —
# BELOW the 500 MiB floor — so every guest is granted the floor and the per-user quota
# stops bounding aggregate growth at all.
#
# What actually bounds it is the keepsake preflight in upload.rs: uploads are refused once
# free < media x 1.1 x 2 + 10 GB, which on 40 GB lands at ~8 GB of media (README, "Sizing
# the disk"). So if a guest reports being blocked, the number to look at is total media,
# not this one.
#
# Raising this still AUTHORISES GUESTS TO FILL MORE OF THE DISK on a larger box, and it
# still eats the headroom the keepsake needs — Gallery.zip and Memories.zip are each
# roughly a second copy of every original (both store media uncompressed). Budget for
# media + 2x media, or move exports to their own volume.
#
# 0.75 is the tested default. Lower it if the box is tight; raise it only if you have
# provisioned export headroom separately.

# ── Workers ───────────────────────────────────────────────────────────────────
# Number of parallel media compression workers. Default 2. Boot-time only.
#
# CORRECTION TO EARLIER GUIDANCE: this used to say "each worker can run an ffmpeg
# transcode, so raise the app memory limit to ~2G if you set 4". There is NO video
# transcode anywhere in this codebase — services/video.rs runs
# `ffmpeg -ss <t> -i <src> -vframes 1 -vf scale=...`, a single poster frame, and video
# originals are stored and served byte-for-byte. Poster extraction costs ~150-250 MB
# for a moment; it is not the constraint.
#
# The real memory consumer is the IMAGE path. `image` 0.25's resize builds an Rgba32F
# intermediate at 16 BYTES PER PIXEL, sized (source_width x target_height) — which the
# 256 MiB decode guard in imaging.rs does NOT cover. Peak per photo, decode + the 2048px
# display resize: ~145 MB at 12 MP, ~223 MB at 24 MP, ~354 MB at 48 MP.
#
# So on a 2 vCPU / 4 GB box (e.g. Hetzner CX22) KEEP THIS AT 2:
#   * concurrency 4 would put two giants at ~1.5 GB against the 1G app limit — OOM.
#   * and app=2G + db=1G + frontend/caddy 256M each + ~370 MB of OS/Docker exceeds the
#     ~3910 MiB a "4 GB" VM actually reports. Raising the limit oversubscribes the host.
# 4 is only reasonable on the 4 vCPU / 8 GB box README.md documents.
#
# The "two 48 MP photos at once" worst case this number used to be sized against is no
# longer reachable: compression.rs takes an EXCLUSIVE `heavy` permit for any job whose
# estimated peak exceeds HEAVY_IMAGE_BYTES (150 MiB), so two giants serialise no matter what
# this is set to. What concurrency 2 now buys is two ORDINARY phone photos in parallel
# (~145 MB peak each), which is both memory-safe and short enough not to starve the two
# tokio worker threads a 2 vCPU box gets.
#
# Do NOT drop this to 1 hoping to protect the CPU. It halves throughput on the common light
# path for a heavy path that is already serialised, and a longer compression backlog means
# more feed tiles served from full-size originals (VirtualFeed falls back to /original while
# derivatives are pending) — trading a little CPU for a lot of venue-wifi bandwidth.
#
# Throughput at 2 is not the bottleneck anyone thinks it is: ~2.5s per 12 MP photo, so
# 100 photos is ~250 CPU-seconds spread over an entire evening.
COMPRESSION_WORKER_CONCURRENCY=2

# ── Comments ──────────────────────────────────────────────────────────────────
# Master switch for the comment feature. Boot-time only (NOT in the admin UI), so it
# needs a `docker compose up -d` to apply. Anything other than false/0/no/off is on.
#
# When false the backend rejects NEW comments with 403 and the frontend hides the whole
# comment UI, including in the offline keepsake viewer. Likes and captions are entirely
# separate features and are unaffected. Existing comments stay in the database (hidden),
# so flipping it back restores them.
#
# Note it gates POSTING only: GET /upload/{id}/comments still serves already-existing
# comments, and the keepsake's data.json still embeds their text. Irrelevant if the flag
# is off from the first boot, since no comment can ever have been written.
# NOTE for the current deployment: `docker-compose.yml` PINS this to "false" on the app
# service, and `environment` overrides `env_file` — so changing it here has no effect in
# production. Remove that line from the compose file first if you want comments back.
COMMENTS_ENABLED=true

# ── Logging ───────────────────────────────────────────────────────────────────
# SET THIS IN PRODUCTION. Without it the app falls back to
# `eventsnap_backend=debug,tower_http=debug` (see main.rs), and with TraceLayer that is a
# debug line per HTTP request — including every preview and thumbnail fetch. Combined with
# Docker's json-file driver it writes to the same filesystem as the database and the media.
# docker-compose.yml caps each service's logs at 30 MB; this keeps the volume sane in the
# first place. The e2e stack has always used exactly this value.
RUST_LOG=eventsnap_backend=info,tower_http=warn