# `Image.Plug.SourceResolver.File`
[🔗](https://github.com/elixir-image/image_plug/blob/v0.1.0/lib/image/plug/source_resolver/file.ex#L1)

Source resolver that reads images from a configured root directory.

Maps `%Image.Plug.Source{kind: :path, ref: "/foo/bar.jpg"}` onto
`<root>/foo/bar.jpg`. Only `:path` sources are accepted.

Decoding is streaming-friendly: the file path is passed straight to
`Image.open/2`, which lets libvips mmap or progressively decode
rather than slurping the file into a binary first.

### Configuration

* `:root` (required) — absolute path to the directory under which
  source files live. Must exist at boot time. Symlinks pointing
  outside the root are rejected at request time.

### Security

Path-traversal is blocked at two levels: `Image.Plug.Source.path/1`
rejects `..` segments before the source even reaches the resolver,
and the resolver re-validates that the canonical resolved path is
still inside the root.

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*Consult [api-reference.md](api-reference.md) for complete listing*