Using mod_http_file_share with an external upload service

Normally, mod_http_file_share handles both the XMPP and the HTTP parts of the XEP-0363: HTTP File Upload protocol. The module does however support letting a 3rd party service handle the HTTPS part, using a JWT token to authenticate.

This is not for running behind a reverse proxy.

For such use case see general HTTP server settings.

Using a separate HTTP upload service

To use an external upload service, specify the base URL of via http_file_share_base_url and configure a strong shared secret via http_file_share_secret, which must also be specified in the configuration of the external upload service.

Component "upload.example.org" "http_file_share"
http_file_share_secret = "U2VjcmV0VG9rZW4wMzYz"
http_file_share_base_url = "https://share.example.com/upload.php/"

External upload protocol details

The external protocol works by passing various details in a JSON Web Token in an Authorization header.

Example payload:

{
   "exp" : 1612113460,
   "expires" : 1612717960,
   "filename" : "picture.png",
   "filesize" : 7168,
   "filetype" : "image/png",
   "iat" : 1612113160,
   "slot" : "RVbKAgWPcrUYAodj",
   "sub" : "user@example.com"
}

This is normally signed with the HS256 algorithm (HMAC-SHA-256). The fields are as follows:

slot: Unique identifier for this upload.
iat: UNIX timestamp of when the token was issued.
exp: UNIX timestamp after which the token should be considered expired.
sub: Identity of the uploader, for per-user quotas.
filename: Name of the file being upload.
filesize: Size of the file, in bytes. Ensure this matches the size of the upload.
filetype: MIME type of the file. Ensure this is the content type the file is served with.
expires: UNIX timestamp after which the file should be considered expired.

Example request (line breaks for readability):

PUT /base_path/RVbKAgWPcrUYAodj/picture.png
Content-Type: image/png
Content-Length: 7168
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.
    eyJmaWxlbmFtZSI6InBpY3R1cmUucG5nIiwic2xvdCI6IlJWYktBZ1dQ
    Y3JVWUFvZGoiLCJmaWxlc2l6ZSI6NzE2OCwiZXhwIjoxNjEyMTEzNDYw
    LCJzdWIiOiJ1c2VyQGV4YW1wbGUuY29tIiwiZmlsZXR5cGUiOiJpbWFn
    ZS9wbmcifQ.7iiwBKcxCSx-UJQaVmj3CpYvIAve4SCmGJwiw4Fmjgc

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A simpler external upload protocol can be found in the community module mod_http_upload_external.