Soliditas

A matrix media proxy as cloudflare worker.

Environment variables

• HOSTNAME: the hostname, for example example.org
• SERVERNAME: the servername, for example example.org

Constructing media id

Example in TypeScript, as seen in mxcId.ts:

function toBase64Url(value: string): string {
  const bytes = new TextEncoder().encode(value);
  let binary = '';

  for (const byte of bytes) {
    binary += String.fromCodePoint(byte);
  }

  return btoa(binary).replaceAll('+', '-').replaceAll('/', '_').replaceAll(/=+$/g, '');
}

function toMatrixID(fname: string, prefix: string): string {
  const base64 = toBase64Url(fname);
  return prefix + base64;
}

You can test it against the /_soliditas/adressconvert?remoteType=[remoteType]&remoteId=[remoteID] endpoint.

Supported proxied upstreams

Giphy

You need to generate a matrix id, using the algorithm as shown above.

Example:

1. The giphy id is yXPquATCb8kGk, this has been translated using the toMatrixID function, see above, to giphy_XPquATCb8kGk.
2. mxc: mxc://example.org/giphy_XPquATCb8kGk
3. will return a redirect to https://i.giphy.com/yXPquATCb8kGk.webp

Tenor

You need to generate a matrix id, using the algorithm as shown above.

Example:

To-Do

Klipy

You need to generate a matrix id, using the algorithm as shown above.

Example:

1. The path on the klipy cdn is ffd4ac143e6335ac68951b787d3c1902/e8/3a/5LM0jRpL.gif
2. mxc: mxc://example.org/klipy_ZmZkNGFjMTQzZTYzMzVhYzY4OTUxYjc4N2QzYzE5MDIvZTgvM2EvNUxNMGpScEwuZ2lm
3. will return a redirect to https://static.klipy.com/ii/ffd4ac143e6335ac68951b787d3c1902/e8/3a/5LM0jRpL.gif

Link previews

GET /_soliditas/preview_url?url=[url] answers in the shape of the Matrix /preview_url endpoint. Missing og: tags are filled from twitter: tags, <title>, <meta name="description"> and oEmbed. Twitter/X links are read from the FxTwitter API, Reddit and TikTok titles from their oEmbed endpoints, Tumblr posts without an image get the fxtumblr render, and Misskey-family notes show their images from the ActivityPub object unless marked sensitive, instead of the author's avatar.

og:image is returned as mxc://[servername]/og_[base64url of the image url]. When a post has more than one image, com.sable.images lists up to ten of them as { url, width, height }, and og:image stays the single image other clients show (the FxTwitter mosaic for tweets).

License

This project is licensed under Apache 2.0, see LICENSE.