A Day in a Pile of Work

My personal Web development blog

Twelvth week update (from 29/06/15 to 17/07/15) in Valum

I have been very busy in the last weeks so this update will cover the work of three weeks instead of a typical bi-weekly update.

There’s no release announcement as I have been working on the assignment I have to realize with the framework and steadily worked toward the 0.2.0-beta release.

Alongside, I have been working on feature for the 0.3 serie which will introduce middlewares. I have prototyped the following:

  • HTTP authentication (basic and digest)
  • content negociation
  • static resources

I have also introduced then in Route, which is a really handy feature to create handling sequences and implemented the trailer from the chunked encoding.

Update from Colomban!

I had an unexpected update from the developer of CTPL, Colomban Wendling. We have talked a few weeks ago about the possibilities of having GObject Introspection into the library so that we could generate decent bindings for Vala.

He’s got something working and I will try to keep a good eye on the work so that we can eventually ship a better binding for the templating engine.

CTPL is a good short-term solution for templating and if the library evolves and integrates new features, it could possibly be a replacement for a possible Mustache implementation.

The two big issues with CTPL is the lack of basic features:

  • filters
  • mapping
  • array of array

Filters let one attach a function to the environment so that it can be applied on the variables instead of pre-processing the data.

Mappings could be easily implemented if Ctpl.Environ would be allowed to contain themselves.

Containers are limited to hold scalars of the same type, which is quite restrictive and prevents many usages.

Working prototype

I have a working prototype for the assignment that I will briefly describe here.

In order to expose the algorithm developed by Nicolas Scott for his Ph. D thesis, I decided to describe a RESTful API with the following endpoints:

PUT /task
GET /task/{uuid}
DELETE /task/{uuid}
GET /task/{uuid}/results
GET /tasks
GET /statistics

The task is still a very generic concept as I do not know much about what kind of data will be poured into the program.

  1. client submits a task with its data
  2. the task is created (stored in memcached) and then queued in a ThreadPool
    • the pool eventually process the task in a worker thread
  3. client requests the results of the task and either one of the following scenario occurs:
    • the task is queued or processing and a 4xx is thrown
    • the task is completed and the result is transmitted

I have finished bindings for libmemcachedutil, which provides a connection pool which has roughly doubled the throughput.

There’s still a few things to do:

  • GLib.MainLoop integration for libmemcached bindings to let the loop schedule request processing and memcached operations
  • client based on Semantic UI (in progress…)

Semantic UI has nice API mapping capabilities that will be very useful to present the data interactively.

The project will be containerized and shipped probably on Google Compute Engine as it supports Docker.


This feature is really handy as it is common to reuse the matching process for a sequence of handling callbacks. I will be introduced in the 0.3 branch as it will work nicely along middlewares.

app.get ("", (req, res, next) => {
    // step 1
}).then ((req, res, next) => {
    // step 2
}).then ((req, res) => {
    // step 3

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