Integrating Go with C: the ZooKeeper binding experience

Posted on 2010/12/10 by niemeyer

ZooKeeper is a clever generic coordination server for distributed systems, and is one of the core softwares which facilitate the development of Ensemble (project for automagic IaaS deployments which we push at Canonical), so it was a natural choice to experiment with.

Gozk is a complete binding for ZooKeeper which explores the native features of Go to facilitate the interaction with a ZooKeeper server. To avoid reimplementing the well tested bits of the protocol in an unstable way, Gozk is built on top of the standard C ZooKeeper library.

The experience of integrating ZooKeeper with Go was certainly valuable on itself, and worked as a nice way to learn the details of integrating the Go language with a C library. If you’re interested in learning a bit about Go, ZooKeeper, or other details related to the creation of bindings and asynchronous programming, please fasten the seatbelt now.

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Posted in Architecture, Article, C/C++, Go, Project, Snippet | 3 Comments

Removing seatbelts with the Go language for mmap support

Posted on 2010/11/28 by niemeyer

Continuing the sequence of experiments I’ve been running with the Go language, I’ve just made available a tiny but useful new package: gommap. As one would imagine, this new package provides access to low-level memory mapping for files and devices, and it allowed exploring a few new edges of the language implementation. Note that, strictly speaking, some of the details ahead are really more about the implementation than the language itself.

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Posted in Architecture, Go, Python, Snippet | 8 Comments

Interfaces and the design of software

Posted on 2010/11/09 by niemeyer

A while ago Martin Pool made a very interesting post on the design of interfaces, inspired by a talk from Rusty Russel from 2003.

Besides the interesting scale of interface quality explained there, this is a very insightful comment, often overlooked:

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Posted in Architecture, Article, Test | Leave a comment

Gocheck: A rich testing library for Go

Posted on 2010/11/06 by niemeyer

It’s time to release my “side project” which has been evolving over the last several months: Gocheck. I’ve been watching Go for some time, and have been getting more and more interested in the language. My first attempt to write something interesting in it made it obvious that there would be benefit in having a richer testing platform than what is available in the standard library. That said, I do understand why the standard one is slim: it’s pretty minimalist, because it’s used by itself to test the rest of the platform. With Gocheck, though, I don’t have that requirement. I’m able to trust that the standard library works well, and focus on having features which will make me more productive while writing tests, including features such as:

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Posted in Architecture, Go, Project, Test | 4 Comments

Introducing The Hacking Sandbox

Posted on 2010/09/25 by niemeyer

When I started programming in Python long ago, one of the features which really hooked me up was the quality interactive interpreter offered with the language implementation. It was (and still is) a fantastic way to experiment with syntax, semantics, modules, and whatnot. So much so that many first-class Python practitioners will happily tell you that the interactive interpreter is used not only as a programming sandbox, but many times as the their personal calculator too. This kind of interactive interpreter is also known as a REPL, standing for Read Eval Print Loop, and many languages have pretty advanced choices in that area by now.

After much rejoice with Python’s REPL, though, and as a normal human being, I’ve started wishing for more. The problem has a few different levels, which are easy to understand.

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Posted in C/C++, Erlang, Go, Haskell, Java, Lua, Perl, Ruby | 10 Comments

Python has a GIL, and lots of complainers

Posted on 2010/07/09 by niemeyer

I’ve just read a post by Brett Cannon where, basically, he complains about complainers.

If you don’t know who Brett is, you’re probably not a heavy Python user. Brett is a very important Python core developer which has been around for a while and who does a great job at it. His post, though, makes me a bit sad.

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Posted in Erlang, Go, Python | 36 Comments

Support for Launchpad and Bazaar in goinstall

Posted on 2010/07/03 by niemeyer

The patch submitted last weekend to support Launchpad and Bazaar in goinstall went in!

This means that once the next release of Go is out (or you sync up with the tip code) you’ll be able to host modules for Go in Launchpad and people will be able to install it by running something similar to:

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Posted in Go, Patch, RCS | Leave a comment

Mocker 1.0 for Python released!

Posted on 2010/06/20 by niemeyer

After a few years in development, version 1.0 of Mocker is now available! Check out the changes since 0.10.1, the supported features, or go straight to the download page.

Posted in Project, Python, Test | 4 Comments

Integrating IRC with LDAP and two-way SMSing

Posted on 2010/06/19 by niemeyer

A bit of history

I don’t know exactly why, but I’ve always enjoyed IRC bots. Perhaps it’s the fact that it emulates a person in an easy-to-program way, or maybe it’s about having a flexible and shared “command line” tool, or maybe it’s just the fact that it helps people perceive things in an asynchronous way without much effort. Probably a bit of everything, actually.

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Posted in Architecture, Cloud, Erlang, Mobile, Project, Python | 1 Comment

Released editmoin 1.15

Posted on 2010/06/19 by niemeyer

Version 1.15 of editmoin is now available.

The following changes were made:

  • Moin used to work with numerical IDs for identification, and editmoin was still based on this model. This release adds support for direct authentication as available in current Moin releases. This was inspired by Reimar Bauer.
  • The new file ~/.moin_users is now parsed to obtain usernames, supporting the feature above. Shortcuts are also supported in this file.
  • Added support for textcha question handling.
Posted in Project, Python | Leave a comment