puttaalu
94859fb0d6
Add GET /api/session, an unguarded probe that reports whether the request
carries valid credentials. It returns 200 with {"authenticated":bool} and never
sends WWW-Authenticate, so the static public pages can check login state without
triggering the browser's Basic-auth dialog. To keep it from being a
password-guessing oracle that bypasses the /upload limiter, a request with no
credentials is answered cheaply as false, while wrong credentials go through the
same failed-attempt limiter (429 once drained).
static/session.js, loaded by every page template, calls it and, only when
authenticated, builds a fixed toolbar: Upload / Manage links, an "Edit this"
link on photo pages (via <body data-slug>, deep-linking to /manage?edit=<slug>,
which scrolls to and focuses that row), a signed-in indicator, and a log-out
control. Logged-out visitors see nothing and get no dialog.
Log out is best-effort: HTTP Basic has no reliable sign-out (the browser caches
credentials until the window closes), so it overwrites the cached credential and
reloads, which works in some browsers but not all. A dependable logout would
need cookie sessions.
269 lines
15 KiB
Markdown
269 lines
15 KiB
Markdown
# photogallery
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Personal static photo gallery with Atom feed and upload API. Single-user.
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No database, no framework — just a Go binary that watches a directory and regenerates a static site.
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An Android app in `android/` posts to the same upload API.
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## Architecture
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```
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content/ # images + .toml sidecars (source of truth)
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public/ # generated output (served by nginx / --serve flag)
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templates/ # embedded HTML templates
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static/ # embedded CSS + JS
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android/ # Kotlin/Compose uploader app, own flake
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```
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The binary does three things at once:
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- Watches `content/` via fsnotify and rebuilds on any change
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- Serves a multipart upload API at `POST /upload`
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- In dev mode (`--serve`), also serves `public/` as static files
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Routes: `GET /upload` (HTML upload form), `POST /upload` (multipart),
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`GET /manage` (edit/delete UI), the manage API under `/api/` (see Manage),
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`GET /health`. Every route except `/health` is gated by HTTP Basic auth when
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`-htpasswd` is set (see Auth).
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In production nginx sits in front: serves `public/` directly, proxies the
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dynamic endpoints (`/upload`, `/manage`, `/api/`) to localhost, terminates TLS.
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Auth is **no longer nginx's job** — the app checks credentials itself
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(`auth.go`), so the nginx vhost just proxies. `/health` is **not** proxied, so
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only `/upload`, `/manage` and `/api/` are reachable from outside the box;
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anything new the app serves needs a matching `location` in `module.nix` or
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nginx will 404 it as a missing static file.
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## Auth
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`-htpasswd <file>` points at an Apache htpasswd file — **bcrypt only**, generate
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with `htpasswd -B`. Each `POST /upload` and `GET /upload` then needs HTTP Basic
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credentials matching a line in that file; `GET /health` stays open. `$2y$`
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(Apache) and `$2a$`/`$2b$` hashes are all accepted; non-bcrypt lines (MD5
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`$apr1$`, SHA, crypt) are skipped with a warning. Empty `-htpasswd` disables
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auth entirely (dev default) and logs a warning — `/upload` is then open.
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`GET /api/session` is a deliberately **unguarded** probe (`handleSession`): it
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reads `r.BasicAuth()`, returns `200 {"authenticated":bool}` and never sends
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`WWW-Authenticate`, so a public page can ask without triggering the browser's
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login dialog. To stop it becoming a password oracle that sidesteps the limiter,
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a request with no credentials is answered cheaply as `false`, while one with
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*wrong* credentials runs through the same failed-attempt limiter (429 once
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drained). `static/session.js` (loaded by every page template) calls it and, when
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authenticated, builds a fixed toolbar with Upload / Manage / "Edit this"
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(`/manage?edit=<slug>`, from the photo pages' `data-slug`) links and a
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signed-in indicator. "Log out" is best-effort only — HTTP Basic has no reliable
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sign-out; a dependable one would need cookie sessions.
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Verification lives in `auth.go`: unknown users still pay for one bcrypt
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comparison (against a dummy hash) so timing can't enumerate usernames, and
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**failed** attempts draw from a token-bucket limiter (`golang.org/x/time/rate`,
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~1/s, burst 10) that returns `429` once drained — successful and bulk uploads
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never touch it. Both apps (Android, Qt desktop) already send Basic auth, so no
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client change was needed. Deps: `golang.org/x/crypto/bcrypt`, `golang.org/x/time/rate`.
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## Manage (edit / delete)
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`GET /manage` is an auth-gated web page (`templates/manage.html`) for editing
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and deleting posts; it is **not linked from the public site** (reach it by URL).
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Its API, all behind the same Basic auth and handled in `manage.go`:
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- `GET /api/photos` — every post as JSON (`slug, caption, date, tags, thumb, url`), newest first.
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- `POST /api/edit` — rewrite one post's sidecar (`slug, caption, date, tags`). The slug (and URL) never changes; editing only touches the `.toml`.
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- `POST /api/tags` — bulk add/remove tags across posts (`slugs` CSV + `add`/`remove` CSV), leaving each post's caption and date intact.
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- `POST /api/delete` — move posts (`slug` repeated, or `slugs` CSV) to `content/.trash/` (timestamp-suffixed, reversible), **not** a hard delete.
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- `GET /api/trash` — list trashed items (`id` = `<slug>.<stamp>`, `slug`, `deletedAt`, `image`, `hasMeta`), newest first.
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- `POST /api/restore` — move a trashed item (`id`) back to `content/`, stripping the timestamp. Refuses with `409` if a live post already holds that slug.
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- `POST /api/trash/empty` — **hard delete** trashed items: specific `id`s (repeated), or everything with `all=1`. The only non-reversible delete in the system.
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The manage page has a Trash panel (header toggle) for restore / delete-forever /
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empty. `trash.go` handles these; filenames parse as `<slug>.<stamp><ext>` (slug
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is dot-free and the stamp is a fixed `20060102-150405`, so parts peel off
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unambiguously), and `id`s are validated the same way to block traversal.
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Each non-trash mutation triggers the same async rebuild as upload. Sidecars are written
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atomically (temp + rename) so a concurrent build never sees a half-written
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file. Slugs are validated (`resolveSlug`: bare filename only, must name an
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existing content image) which closes path traversal and dotfile access.
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Every state-changing POST (`edit`, `delete`, `tags`, `restore`, `trash/empty`)
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first passes `sameOrigin` (`server.go`): because Basic-auth credentials are
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replayed by the browser on every request to the host, a cross-site page could
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otherwise drive a logged-in user into a delete (CSRF). The check honours
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`Sec-Fetch-Site`, falls back to comparing `Origin` against `-base-url`/`Host`,
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and allows header-less non-browser clients (curl). Cross-site → `403`. (Ported
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from the independent `/manage` on `plex/trunk-ng`.)
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**Delete relies on `Build`'s prune step** (`generator.go`): a rebuild drops the
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derived HTML trees (`photo/ day/ album/ page/ grid/page/`) and regenerates them,
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and `pruneRenditions` removes `images|thumbs|medium|og` files with no backing
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photo. Without this a deleted post would linger at its old URL and in stale
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day/album pages. This also cleans up after a sidecar removed by hand.
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## Stack
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- **Go** — stdlib + `BurntSushi/toml`, `fsnotify/fsnotify`, `golang.org/x/image`, `golang.org/x/crypto` (bcrypt), `golang.org/x/time` (rate)
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- **Templates** — `html/template`, embedded via `embed.FS`
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- **Images** — four renditions per photo: original copy, 600×600 centre-cropped square thumbnail, a 1600px-longest-side "medium" for the detail page, and a 1200px "og" for link previews. Catmull-Rom resize. Outputs are skipped when newer than the source.
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- **Feed** — Atom (`encoding/xml`)
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- **NixOS** — `flake.nix` + `module.nix`, exports `nixosModules.default`
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## Sidecar format
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```toml
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caption = "Tempelhof at sunrise"
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date = "2026-06-14"
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tags = ["berlin", "sunrise"]
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```
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Missing sidecar → filename as caption, today as date. Photos sort newest first by that date.
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`tags` is optional, free-text, and defines albums (see below). Tags are
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normalized to lowercase on load/upload (`parseTags` in `albums.go`); a tag may
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contain spaces (`"berlin trip"`), and its URL slug is derived with `sanitiseSlug`.
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## Design
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- Gruvbox dark hard colour scheme
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- Crimson Pro (serif) for headings and captions — configurable via `-serif-family` / `-fonts-url`
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- Manjari for Malayalam text (bio line), via `-ml-family`
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- Two views of the same photos, both 3-column square grid → 2-column on mobile, both with infinite-scroll load-more. Page size is configurable via `-page-size` (default 60; NixOS `services.photogallery.pageSize`). Which view sits at the site root is chosen by `-default-view` (`timeline` or `grid`, default `timeline`; NixOS `services.photogallery.defaultView`): the chosen one owns `/` (`/`, `/page/2/`, …) and the other is published under `/<name>/`. `viewBase`/`pageURL` (`generator.go`) derive every page path, pager link and the Timeline↔Grid cross-links (`TimelineURL`/`GridURL` in the template data) from that one setting; `Build` removes both `timeline/` and `grid/` each run so a flipped default leaves no stale root behind.
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- **Timeline** (the default root): photos grouped by calendar day — one ISO date heading (`2026-06-14`) + count per day, then the square grid. `groupByDay` collapses the newest-first list into consecutive same-day runs; `chunkDayGroups` packs whole days into pages targeting `pageSize`, never splitting a day across a page boundary (so appended pages never duplicate a heading — the load-more JS relies on this).
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- **Grid** is the flat square grid. At `/grid/` by default, or at the root when `-default-view grid`.
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- Each timeline date heading links to a **single-day page** (`/day/<YYYY-MM-DD>/`) holding just that day's photos. `renderDayPages` writes one per `groupByDay` run; the ISO label doubles as the URL slug.
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- Single photo page with sidebar and newer/older navigation
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### Albums (tags)
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A second grouping axis, parallel to days: an album is just a tag (`albums.go`).
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`groupByTag` mirrors `groupByDay`, and `renderAlbumPages` writes a paginated
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square-grid album per tag at `/album/<slug>/` (like the grid view). `/albums/`
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is the index of every tag with counts; `/tags.json` is the machine-readable tag
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list (`[{tag, slug, count}]`, served statically like `feed.xml`). Tags show on
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each photo page and link to their album; an **Albums** link sits in the
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timeline/grid header. Tags are assigned at upload via the `tags` field on
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`POST /upload` (comma-separated) or by editing a sidecar's `tags`. All derived at
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build time — no database.
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### Link previews
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Photo pages carry Open Graph + Twitter-card meta tags so a shared link unfurls
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in WhatsApp, Telegram, etc. `generateOG` writes a dedicated `public/og/`
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rendition — 1200px longest side, quality laddered down until under ~250 KB,
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because WhatsApp drops the preview above ~300 KB and the medium rendition can
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exceed that. The `og:image` URL is absolute (`{{.BaseURL}}/...`); both crawlers
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ignore relative image paths, and previews only work against the deployed
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`-base-url`, never `http://localhost`. `og:image:width`/`height` come from
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`DecodeConfig` on the OG file, read even when the file itself was skipped as up
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to date. Both platforms cache per URL — after a deploy, re-scrape via
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`@webpagebot` (Telegram) or Facebook's sharing debugger (WhatsApp).
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### Photo page navigation
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`static/photo-nav.js` handles arrow keys and touch swipe. Both read their
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destinations from the `[data-nav="newer"]` / `[data-nav="older"]` anchors the
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template renders, so a photo with no sibling in that direction has nothing to
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find and the gesture rubber-bands. If the script fails to load the links still
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work.
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Swipe left → older, right → newer, matching ArrowRight/ArrowLeft. Constraints
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worth knowing before touching it:
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- Swipes starting within 24px of a screen edge are ignored — that strip is the browser's own back-gesture.
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- Only `pointerType === "touch"`, so desktop drag-to-save is untouched.
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- Axis locks once after 10px so vertical drags stay scrolls; `touch-action: pan-y` tells the compositor the same.
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- The image is wrapped in an `<a>` to the full-size original, so the click trailing a swipe is suppressed or it opens a new tab.
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- `EXIT_MS` in the JS must stay in sync with the transition duration in `style.css`.
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Anything added under `static/` is embedded and copied to `public/static/`
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automatically — `assets.go` embeds the whole directory and `copyStatic()` walks
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every entry, so new CSS/JS needs no generator change.
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## Running locally
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```bash
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nix develop
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go mod tidy
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go run . --serve
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# gallery: http://localhost:8080
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# upload: http://localhost:8080/upload
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```
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## Android app
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Kotlin + Jetpack Compose uploader: pick or share a photo, add caption and date, post. Credentials (HTTP Basic) are sealed with an Android Keystore AES-GCM key. See `android/README.md` for the detail.
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Its own flake, deliberately separate from the root one so NixOS consumers of `nixosModules.default` don't pull the Android SDK into their lock:
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```bash
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cd android
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nix develop
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./gradlew assembleRelease # app/build/outputs/apk/release/app-release.apk
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```
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The server needs no changes to serve it — every gap (slug collisions, EXIF, HEIC, size caps) is closed client-side. Release builds need `android/keystore.properties`; without it the signing config is skipped and only debug builds work.
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## NixOS module usage
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```nix
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inputs.photogallery.url = "github:youruser/photogallery";
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# in modules:
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inputs.photogallery.nixosModules.default
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# in configuration.nix:
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services.photogallery = {
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enable = true;
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baseURL = "https://photos.yourdomain.tld";
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# bcrypt htpasswd (`htpasswd -B`); handed to the service via LoadCredential,
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# so a root-owned 0400 secret is fine. Omit to leave /upload open.
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htpasswdFile = "/run/secrets/photogallery-htpasswd";
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nginx = {
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enable = true;
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domain = "photos.yourdomain.tld";
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};
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};
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```
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## Bootstrap (first nix build)
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```bash
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go mod tidy # generates go.sum — commit it
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nix build # fails, prints correct vendorHash
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# paste hash into flake.nix
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nix build # succeeds
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```
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## Key files
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| File | Purpose |
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| `main.go` | Flags, wires generator + watcher + server |
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| `generator.go` | Scans content dir, renders HTML + Atom feed, generates thumbs/mediums |
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| `albums.go` | Tag parsing/normalization, `groupByTag`, album pages + `/albums/` + `/tags.json` |
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| `server.go` | Upload API + optional static file serving |
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| `auth.go` | htpasswd (bcrypt) HTTP Basic auth + failed-attempt rate limit for `/upload` |
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| `manage.go` | Edit/delete API (`/api/photos`, `/api/edit`, `/api/tags`, `/api/delete`) + trash move + atomic sidecar writes |
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| `trash.go` | Trash API: list (`/api/trash`), `/api/restore`, `/api/trash/empty` (hard delete) |
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| `templates/manage.html` | Auth-gated edit/delete web UI at `/manage`, with a Trash panel |
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| `watcher.go` | fsnotify watcher with 500ms debounce |
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| `assets.go` | `//go:embed` for templates and static |
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| `templates/timeline.html` | Site root: photos grouped by day, paginated |
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| `templates/grid.html` | Flat square grid at `/grid/`, paginated |
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| `templates/day.html` | Single-day page at `/day/<date>/` |
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| `templates/album.html` | Album (tag) page at `/album/<slug>/`, paginated |
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| `templates/albums.html` | Album index at `/albums/` |
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| `templates/photo.html` | Single photo page, neighbour links and prefetch |
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| `static/photo-nav.js` | Arrow-key and swipe navigation |
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| `module.nix` | NixOS module (systemd service, tmpfiles, nginx vhost) |
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| `flake.nix` | `buildGoModule` package + devShell + nixosModules |
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| `android/flake.nix` | Android SDK dev shell (separate from the root flake) |
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## Gotchas
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- `.gitignore` patterns here must be anchored. An unanchored `photogallery` also matches the Kotlin package directory `android/app/src/main/java/ws/inflo/photogallery/` and silently swallows every source file in it.
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## What's not done yet
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- ActivityPub federation (planned later — start with RSS/Atom)
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- Edit/delete/trash in the Android and Qt apps (web `/manage` only so far; the `/api/` endpoints are there for the apps to adopt)
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- Any auth beyond the app's htpasswd Basic auth (no sessions, no per-user scopes)
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- The Android app has never been run on real hardware
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- Photo-page swipe has never been tested on a real touchscreen; the iOS Safari edge-gesture interaction is the untested part
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