psi-prod/mehari

A cross-platform library for building Gemini servers

Mehari

Mehari is a cross-platform library for building Gemini servers. It fully implements the Gemini protocol specification.

It takes heavy inspiration from Dream, a tidy, feature-complete Web framework.

Mehari provides several packages. See here. Many examples are also provided.

Installation

opam install mehari

Features

• Mirage OS friendly
• Static files serving
• MIME type inference from file content (using experimental Conan support)
• Rate limit
• Virtual hosting using SNI
• CGI
• Long-running TCP connection

Feedback

Since Mehari is in its early stages, any feedback and contributions regarding the API or security are appreciated.

Important links

• API documentation: https://docs.heyplzlookat.me/mehari/
• Tutorial: https://docs.heyplzlookat.me/mehari/index.html#tutorial
• Issues: https://github.com/Psi-Prod/Mehari/issues

License

Distributed under the LGPL-3.0 License. See license for more information.

mehari's Issues

No mime

Support gemini mime inference

Add support for .gmi file mime inference in Mehari.from_filename.

Functorize implementation of functions related to Gemini protocol

• to avoid semantic differences (like for Mehari_*.load_cert)

Configurable default response

CGI

`Gemtext.to_string` only working for the first line.

Gemtext.quote "text1\ntext2\ntext3" |> Gemtext.to_string

returns

>text1
text2
text3

Support `Mehari.stream` in `Mehari_mirage`

flush labeled is simply ignored by function which writes on socket.

Maybe redesign delayed stream body, inspired by https://aantron.github.io/dream/#type-stream.

Special route path

Pull out some convenient functions from `Dream`

Such as:

• https://aantron.github.io/dream/#val-pipeline
• https://aantron.github.io/dream/#val-no_route
• https://aantron.github.io/dream/#val-no_middleware

Timeout when parsing client request in `Mehari_eio`

SNI

Rename `Mehari_eio` to `Mehari_eio_unix`

To prevent Mirage OS runtime compatibility in the future.

Log

Add `Mehari.target`

As a shortcut for Mehari.uri req |> Uri.path.

Fastest Gemtext parsing

Performance of Mehari.Gemtext.of_string can be improved. Currently, the parser uses regex which is not very efficient.

• Use a buffer
• Speed up parser by removing regex ?

Perform more check on client request

According to specification:

In particular, the authority component is allowed and required, but its userinfo subcomponent is NOT allowed. The host subcomponent is required. The port subcomponent is optional, with a default value of 1965. The path, query and fragment components are allowed and have no special meanings beyond those defined by the generic syntax. An empty path is equivalent to a path consisting only of "/". Spaces in paths should be encoded as %20, not as +.

is a UTF-8 encoded absolute URL, including a scheme, of maximum length 1024 bytes. The request MUST NOT begin with a U+FEFF byte order mark.

Static

Improve static implementation

• Add a "go to parent directory" feature.

Catch `Eio.Exn.Io`.

This exception is introduced in eio 0.7 which is not yet available on opam.

Mehari/mehari-eio/server_impl.ml

Line 105 in a7ac1da

(*| Eio.Exn.Io (Eio.Net.E (Connection_reset _), _) ->

Client certificate in request

Support Fast CGI

Directory listing

• Mehari_eio implementation
• Mehari_lwt_unix implementation

Remove dependence to Lwt_stream in Mehari pure lib

Replace it by Seq for crossplatform

Branding.

Remove UNIX syscall in mirage-eio

Replace mirage-clock-unix by mirage-clock-eio when it becomes available.

IAMISSAM es-tu là c'est long une heure

Allow delayed response in `Mehari.response_raw`

Allow proxy

Currently, server only respond to request containing one of its own hostnames. So proxying is not allowed.

Allow flush in long live TCP stream

Middleware

Malformed header

Rate limiter

Handle more Eio exception

https://ocaml-multicore.github.io/eio/eio/Eio/Net/index.html#type-connection_failure

Improve logging related features

Inspired by https://aantron.github.io/dream/#logging.

Support CGI for Mehari_eio

Waiting for ocaml-multicore/eio#330

More accurate URL check

• Filter out scheme other than gemini
• Filter out url which have wrong host

Check well encoded UTF-8 in client request

Remove zed as dependence and use a less hacky solution.

Rate limit doc

Make `Mehari_mirage` work again.

[...]
TLSv1	Client Hello
TCP	1965 → 53946 [ACK] Seq=1 Ack=518 Win=407744 Len=0 TSval=777244924 TSecr=3541461376
// no server hello!!!!
TCP	1965 → 53946 [FIN, ACK] Seq=1 Ack=518 Win=407744 Len=0 TSval=777244925 TSecr=3541461376
TCP	53946 → 1965 [ACK] Seq=518 Ack=2 Win=408256 Len=0 TSval=3541461377 TSecr=777244925
TCP	53946 → 1965 [FIN, ACK] Seq=518 Ack=2 Win=408256 Len=0 TSval=3541461377 TSecr=777244925
TCP	1965 → 53946 [ACK] Seq=2 Ack=519 Win=407744 Len=0 TSval=777244925 TSecr=3541461377

Virtual hosts router.