# Deployment bootstrap

ZDDC tools (archive, transmittal, classifier, mdedit, landing) are single-file
HTML bundles. The bootstrap pattern lets you install once on a deployment and
update by editing a few lines, without re-uploading multi-megabyte HTML files.

End users install via a short copy-paste shell snippet from the home page's
"Install on your server" section. The snippet uses `curl` to fetch either
the current stable HTMLs (self-contained) or tiny level-2 stubs (channel
trackers) into the deployment directory. The published stubs live under
`https://zddc.varasys.io/bootstrap/`:

- `bootstrap/level1/<tool>.html` — same-origin level-1 stubs (4 tools, no
  landing — landing only lives at deployment root).
- `bootstrap/track-{stable,beta,alpha}/<tool>.html` — per-channel level-2
  stubs (5 tools each).

Both directories are produced by the project's top-level `build.sh` from
`bootstrap/level{1,2}.html.tmpl`.

## The two-level model

A typical `zddc-server` deployment looks like this:

```
<ZDDC_ROOT>/
  index.html                # landing tool (or bootstrap)
  archive.html              # archive tool (or bootstrap; site-wide channel switch lives here)
  transmittal.html
  classifier.html
  mdedit.html
  <project-A>/
    archive.html            # level-1 bootstrap → fetches ../archive.html
    transmittal.html
    classifier.html
    mdedit.html
    <project files…>
  <project-B>/
    archive.html            # level-1 bootstrap (or pinned to a specific version)
    …
```

- **Level-1 stubs** at `<project>/<tool>.html` always fetch the same-origin
  `../<tool>.html`. They never touch `zddc.varasys.io`. Install them once;
  they don't need to change.
- **At deployment root** (`<ZDDC_ROOT>/<tool>.html`), put either:
  - the actual built tool HTML — fully self-contained install, no external
    dependencies; or
  - a level-2 bootstrap — resolves the desired channel against
    `https://zddc.varasys.io/releases/manifest.json` (or skips that step for an
    explicit `?v=X.Y.Z` pin) and fetches the asset from
    `https://zddc.varasys.io/releases/<tag>/<tool>_v<X.Y.Z>.html`. Caddy at
    `zddc.varasys.io` reverse-proxies that to the corresponding Codeberg
    release-asset URL.

The site administrator switches the whole site to a channel by re-running
the `track-<channel>` install snippet from the home page — that overwrites
the root `<tool>.html` files with the matching level-2 stubs. A single
project can override one tool by editing just `<project-X>/<tool>.html`
(replace the relative `upstream` URL with an absolute zddc.varasys.io URL).

## Why two levels

The level-1 stubs let projects share a single source of truth for "which
build of the archive tool runs here." Switching channels is one file change
at the root; pinning a single project is one file change in that directory.

`document.write()` chains across both levels: level-1 fetches and writes,
the new document's level-2 script runs and writes again, the third write
is the actual tool. Origin stays at the deployment domain throughout, so
File System Access API, `crypto.subtle`, and `localStorage` all work and
preferences stay scoped to the deployment.

## Pinning options

There are two ways to choose a version: edit the stub for a permanent
pin, or pass a `?v=` URL parameter for a per-request override.

### 1. Permanent pin (edit the stub)

The level-2 stub resolves channels via `manifest.json` at runtime, so a
"pin to current stable" is the default — no editing required. To pin
this single tool to a specific version permanently, replace the level-2
stub with one that bypasses the manifest:

| To pin                                  | Replace stub body with a fetch of                                       |
|-----------------------------------------|-------------------------------------------------------------------------|
| Exact stable version `vX.Y.Z`           | `https://zddc.varasys.io/releases/<tool>-vX.Y.Z/<tool>_vX.Y.Z.html`     |
| Specific alpha/beta build               | `https://zddc.varasys.io/releases/<tool>-vX.Y.Z-alpha.N/<tool>_vX.Y.Z-alpha.N.html` |
| Channel default (current implementation)| Resolves `<tool>-<channel>` against `releases/manifest.json` at runtime |

### 2. Per-request `?v=` parameter

Both stub levels honor a `?v=` URL parameter. The parameter survives the
`document.write()` chain, so it flows through level-1 → level-2 →
upstream automatically.

| URL parameter                  | Behavior                                              |
|--------------------------------|-------------------------------------------------------|
| `?v=0.0.4` (or `?v=v0.0.4`)    | tries `<tool>_v0.0.4.html` locally, then upstream     |
| `?v=alpha`                     | switches to alpha channel                             |
| `?v=beta`                      | switches to beta channel                              |
| `?v=latest`                    | latest stable                                         |
| (omitted)                      | the default baked into the stub                       |

When level-1 has `?v=…`, it tries `../<tool>_<suffix>.html` first (useful
when the admin has staged specific versions locally) and falls back to
`../<tool>.html` if 404 — which then forwards the parameter via level-2
if one is installed. So the same URL works whether the version is
staged locally, served by a level-2 stub, or both.

Stable releases are immutable. Alpha and beta channel files are
overwritten in place each time their channel is rebuilt; expect them to
change without notice. The build label rendered on the tool page tells
you what you are running (date + commit SHA for alpha/beta, version
number for stable).

## Auditing what's installed

Every stub contains a `fallback` (level-1) or `upstream` (level-2)
constant. To see what each tool / project on the deployment points at:

```sh
grep -rn "fallback\|upstream" <ZDDC_ROOT>
```

## CORS prerequisite (level-2 only)

A level-2 fetch is cross-origin (deployment → `zddc.varasys.io`). The
upstream must serve `Access-Control-Allow-Origin: *` (or a list including
your deployment origin) on `manifest.json` and on each released asset.
Verify with:

```sh
curl -I https://zddc.varasys.io/releases/manifest.json    | grep -i access-control
curl -I https://zddc.varasys.io/releases/archive-v0.0.2/archive_v0.0.2.html \
  | grep -i access-control
```

Level-1 fetches are same-origin so no CORS is involved.

## Templates

`level1.html.tmpl` and `level2.html.tmpl` are the source of truth. The
project's top-level `build.sh` substitutes `{{TOOL}}`, `{{TOOL_TITLE}}`,
`{{CHANNEL}}`, and `{{FAVICON}}` to produce the per-tool stubs published
under `website/bootstrap/level1/` and `website/bootstrap/track-<channel>/`,
which the install snippets curl from `https://zddc.varasys.io/bootstrap/`.