A Day in a Pile of Work

My personal Web development blog

Progress Update in Valum

My up key stopped working, so I’m kind of forced into vim motions.

All warnings have been fixed and I’m looking forward enforcing --experimental-non-null as well.

The response head is automatically written on disposal and the body is not closed explicitly when a status is thrown.

In the mean time, I managed to backport write-on-disposal into the 0.2.12 hotfix.

I have written a formal grammar and working on an implementation that will be used to reverse rules.

VSGI Redesign

There’s some work on a slight redesign of VSGI where we would allow the ApplicationCallback to return a value. It would simplify the call of a next continuation:

app.get ("", (req, res, next) => {
    if (some_condition)
        return next (req, res);
    return res.body.write_all ("Hello world!".data, null);

In short, a boolean returned tells if the request is or will eventually be handled.

The only thing left is to decide what the server will do about not handled requests.

Update (Feb 21, 2016)

This work has been merged and it’s really great because it provides major improvements:

  • no more 404 at the bottom of perform_routing, we use the return value to determine if any route has matched
  • OPTIONS work even if no route has matched: a 404 Not Found would be thrown with the previous approach

Yeah, we are even handling OPTIONS! It produce a 0-length body with the Allow header assigned with a list of available methods for the resource.


The Response class now has a expand and expand_utf8 methods that work similarly to flatten for Request.

app.get ("", (req, res) => {
    return res.expand_utf8 ("Hello world!");

It will deal with writting the head, piping the passed buffer and close the response stream properly.

The asynchronous versions are provided if gio (>=2.44) is available during the build.

SCGI improvements

Everything is not buffered in a single step and resized on need if the request body happen not to hold in the default 4kiB buffer.

I noticed that set_buffer_size literally allocate and copy over data, so we avoid that!

I have also worked on some defensive programming to cover more cases of failure with the SCGI protocol:

  • encoded lengths are parsed with int64.try_parse, which prevented SEGFAULT
  • a missing CONTENT_LENGTH environment variable is properly handled

I noticed that SocketListener also listen on IPv6 if available, so the SCGI implementation has a touch of modernity! This is not available (yet) for FastCGI.

Right now, I’m working on supporting UNIX domain socket for SCGI and libsoup-2.4 implementations.

It’s rolling at 6k req/sec behind Lighttpd on my shitty Acer C720, so enjoy!

I have also fixed errors with the FastCGI implementation: it was a kind of major issue in the Vala language. In fact, it’s not possible to return a code and throw an exception simultaneously, which led to an inconsistent return value in OutputStream.write.

To temporairly fix that, I had to supress the error and return -1. I’ll have to hack this out eventually.

In short, I managed to make VSGI more reliable under heavy load, which is a very good thing.

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