# source.bundesrecht

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Fetch German federal law from gesetze-im-internet.de by slug

## What it does

Resolves a gesetze-im-internet.de slug (e.g. `bgb`, `estg`, `gg`,
`stromnzv`) against the public BMJ publication site, downloads the
law's `xml.zip`, unpacks the BMJ norm XML (gii-norm DTD) and returns
it plus a metadata record. The unpacked bytes are content-addressed
(SHA-256), so the flow's audit trail pins the exact Gesetzesstand
that was processed.

Unlike EUR-Lex, gesetze-im-internet serves only the CURRENT
consolidated state — there is no URL for an older version. The
SHA-256 (plus the BMJ `builddate` from the XML header) is what makes
a later re-fetch comparable: a change upstream becomes visible
instead of silent.

Public BMJ data only; network permission is pinned to
`www.gesetze-im-internet.de`.

## How to use

```yaml
steps:
  - id: fetch
    use: source.bundesrecht@^0
    with:
      gesetz: stromnzv

  - id: normalize
    use: text.akoma-normalize@^0
    with:
      content: $fetch.xml
```

The slug is the path segment of the law's page on
gesetze-im-internet.de: `https://www.gesetze-im-internet.de/<slug>/`.

## Outputs

- `xml` — the BMJ norm XML as unpacked from the site's archive.
  Feed into `text.akoma-normalize` for the structured
  Akoma-Ntoso-aligned representation (its v0.1 BMJ adapter handles
  this format natively).
- `meta` — JSON SourceMeta: `gesetz`, `url`, `source_sha256`,
  `byte_len`, and `builddate` when the XML header carries one.

## Errors

- Unknown slug → clear invalid-input error naming the checked URL.
- Non-ZIP or XML-less download, HTML error pages → internal error
  with the reason; nothing HTML-shaped is ever passed downstream.