Giacomo Vacca

I've presented a workshop at Kamailio World 2016 . It focused on tools to help automating the build, deployment and test of Kamailio -based applications using Jenkins , Docker and a few other technologies. It's been also an opportunity to show a sample usage of the new http_async_client module, designed to perform non-blocking HTTP queries from Kamailio. The interested reader can find the slides here: Continuous Integration and Kamailio from Giacomo Vacca And if you have an hour to spare, here's the full video: Any feedback or question you may have, please get in touch. I have a post on the event in progress, but there are so many things to highlight that it will require some more time. Many thanks to Daniel and Elena-Ramona ( more info here ), event hosts, and Pascom.net for video streaming, recording and editing.

From time to time I need to verify that the audio inside a trace is as expected. Not much in terms of quality, but more often content and duration. A few years ago I wrote a small program to transform a pcap into a wav file - the codec in use was SILK. These days I'm dealing with Opus , and I have to say things are greatly simplified, in particular if you consider opus-tools , a set of utilities to handle opus files and traces. One of those tools, opusrtp , can do live captures and write the interpreted payload into a .opus file. Still, what I needed was to achieve the same result but from a pcap already existing, i.e. "offline". So I come up with a small - quite shamlessly copy&pasted - patch to opusrtc, which is now in this fork . Once you have a pcap with an RTP stream with opus (say in input.pcap ) you can retrieve the .opus equivalent (in rtpdump.opus ) with: ./opusrtp --extract input.pcap Then you can generate an audible wav file with: ./opusd...

"I’ve been following  TADHack  and its related events for some time, and finally this month I got the opportunity to attend  TADHack-mini Paris . Participants can join from remote too, but the personal full immersion is something different (even, ironically, when the topic is Real Time Communications, and more in particular  WebRTC  and Telecom APIs. We met in central Paris [...] " This is the beginning of the behind-the-scenes story about my TADHack participation. You can read  my full article here .

I was very happy to see the news of the release of a new Kamailio module, authored by Victor Sveva . CFGT can be used to test call scenarios and see what routing logic was triggered in Kamailio. Test calls need to be marked with a specific, configurable Call-ID pattern ('callid_prefix'). A JSON report is generated, with the possibility to choose what variables to dump into it. This is going to greatly simplify testing, while potentially keep the logging to a minimum. Highly recommended.

This is a topic I really care about. Please take a look at the slides (they are quite verbose) used in a seminar at a local developers group: Docker and Puppet for Continuous Integration from Giacomo Vacca

There are scenarios where TLS 1.2 is not just enabled, but the only one accepted. In these cases many clients fail to connect over HTTPS. I needed to be able to use 'git clone https://...' on CentOS 7, and since it was failing and I spent some time on a work around, I'm sharing it here. The system is a CentOS 7 host on DigitalOcean, with kernel Linux 3.10.0-123.8.1.el7.x86_64 git is 1.8.3 , the stock version nss is 3.19.1-5.el7_1 If I do something like curl  --tlsv1.2  https://freeswitch.org the connection is successful, but a command like GIT_CURL_VERBOSE=1 git clone  https://freeswitch.org/stash/ scm/fs/freeswitch.git was giving a connection error with this code: NSS error -12190 (SSL_ERROR_PROTOCOL_VERSION_ ALERT) (freeswitch.org only accepts TLSv1.2). Long story short, I read somewhere that git 2.6 had support for configuring TLSv1.2, and I downloaded the source code of git 2.6.0 from  https://www.kernel.org/ pub/software/...

The other day I was browsing the slides of "Continuous Deployment with Jenkins" , from PuppetLabs . One sentence in particular I found relevant for what I was doing, and important in general: Puppet manifests are code too. To be honest, I don't think I need to sale this very hard, so I'll proceed to a practical consequence: unit testing for puppet modules . Unsurprisingly, there's a app tool for that: rspec-puppet . At least this is what I've been using for some time and find very useful and easy to use. I've even created some Jenkins jobs just to unit test Puppet modules. You can find a tutorial for rspec-puppet here . Feel free to leave this article, read the tutorial, experiment a little and come back later. What I wanted to share is some tricks/settings that I had to use, which I haven't found in one single place so far. As you can see in the tutorial, rspec-puppet generates a dir skeleton for you (with the command 'rspec-puppet in...