C::Blocks Advent Day 6

This is the C::Blocks Advent Calendar, in which I release a new treat each day about the C::Blocks library. Over the last few days I have illustrated how to use C::Blocks to write procedural code, how to get data across the Perl/C divide, including using types to do that concisely, and how to write code that is shared across modules and scripts. Yesterday I provided some benchmarks that I hope give a sense for the performance of C::Blocks, and start to indicate the circumstances when it might be useful. Today I am going to illustrate the many ways you can generate and/or modify your C code using C::Blocks including source filters, interpolation blocks, and the good old string eval.

Dist::Zilla Tempate

It is still POD day here at the Dist-Pen

I spent the day trying to get a little deeper into POD::Weaver to understand how it works rather than just aping the three lines I have seen in the odd tutorial or should I say tuturial-ette;

[@Default]

[-Transformer / List]
transformer = List
The fist thing to know about POD::Weaver is if you want to use it any deeper than the above then don't bother going to its home-page on CPAN there is not much there to get started on.

Not faulting the documentation at all it is quite comprehensive and perfect if you are going to create a project like podweaver.

meta::hack 2016

MetaCPAN is the community developed and maintained website and api for finding and learning about Perl modules. This year, we dedicated a long weekend to improving it and oh what a weekend it was!

You can import your Metacpan favorites into perlmodules.net!

PerlModules.net is a website that notifies you when your favorite modules get updated, via e-mail or RSS.

As of today, you can now import your favorites from metacpan.org into perlmodules.net.

And if your metacpan favorites list changes in the future, no worries: the corresponding feed in your perlmodules.net account will adapt accordingly.

C::Blocks Advent Day 4

This is the C::Blocks Advent Calendar, in which I release a new treat each day about the C::Blocks library. Yesterday I showed how to get information across the boundary between Perl and C with minimal boiler plate. Today I explain how to declare and use C functions. I also explain the killer feature of C::Blocks: declaring C functions and other things within a module that can be used throughout your code.

Dist::Zilla and Weaver. Play Nice!

Small problem solving day here in the Dist-Pen.

Just a quick post-ette today to resolve the problem I was having in my last post, where I was trying to get [PodWeaver] to work with 'Pod::Elemental::Transformer'.

I was trying to get this;

=head1 Table Of Contents
=for :list
* Database::Accessor::Tutorial::GettingStarted
* Database::Accessor::Tutorial::Basics
=cut 
to work for my POD but it just did not want to play ball with me. I know this should work as I have seen it used in all sorts of other places and in the two tutorials I ran across.

Static code analysis with Perl and SonarQube

When managing code quality for bigger projects, SonarQube is the de-facto standard for many programming languages. Not for perl, as there has not been any perl integration into SonarQube yet.

We have Perl::Critic, a fantastic linting tool, but what if we could track our Perl::Critic issues in our projects over time? What if we had a webinterface where we could extract statistics about certain issue types? What if we could combine this with code coverage information? All this is about to come...

Come join me on my new open source project "sonar-perl": https://github.com/otrosien/sonar-perl -- I'm looking forward to it!

Perl 5 Porters Mailing List Summary: November 21st-30th

Hey everyone,

Following is the p5p (Perl 5 Porters) mailing list summary for the past week and a half.

Enjoy!

meta::hack Wrap-up Report

We had a great four days at meta::hack a couple of weeks ago. I've tried to briefly summarize what we accomplished.

He's Back!!!

Just when you think the Dist::Zilla is gone, I am going to go back to the Dist-Pen for the next few posts.

I could just spend the next thirty posts or so writing up a new POD each day and posting the results here. I wouldn't learn anything though, I alreay know how to write POD, and I am sure I would loose any readers I might of gained over the last few weeks. So I think I will spare us that and instead re-visit Dist-Zilla today.

I am going to re-vist how I am using [PodWeaver] plugin, as I am facing some thirty POD files that will have a good deal of boiler plate in them and I would like to have some things just done for me.

To investigate how Pod::Weaver works I created only a single POD today 'Manual.pod' with just this in it

Introducing Net::ACME

I’ve recently finished porting cPanel’s implementation of Let’s Encrypt’s ACME (Automatic Certificate Management Envirionment) protocol to a new CPAN module, Net::ACME.

Net::ACME offers a number of attractive features:

- It’s based closely on cPanel’s widely used Let’s Encrypt plugin.

- Memory usage is light: no Moose/Moo/etc.

- It can run in pure Perl, as long as you have an OpenSSL binary. (Otherwise, it needs Crypt::OpenSSL::RSA.)

- Thorough error checking—even Perl calling context!

- Errors are represented as typed, queryable exceptions. (The framework includes its own exception class hierarchy.)

- It’s “global clean”: no careless overwriting of variables like $@, $!, $?, etc.

The object hierarchy also closely mirrors ACME’s own object hierarchy: separate classes exist to represent ACME registrations, authorizations, challenges, and certificates.

The distribution includes example scripts that demonstrate usage of the module and should also give a good feel for the protocol itself.

I hope it’s useful!

Backticks and tests in Perl 6

Perl was created for systems administration, and Perl 6 has all the chops you've come to expect from the brand. Here I needed to use MD5 checksums from my collaborator to verify that I downloaded all their data without errors. Each data "$file" has an accompanying "$file.md5" that looks like this:

$ cat HOT232_1_0770m/prodigal.gff.md5
a36e4adfaa62cc4adb8cea44c4f7825f  HOT232_1_0770m/prodigal.gff

So I need to read the contents of this file, get just the first field, then execute my local "md5" (or "md5sum") program on the file without the ".md5" extension and determine if they are the same. All standard stuff, and I think Perl 6 gives us elegant ways to accomplish all of these, including a dead-simple testing framework. Here's my solution:

Security release - use after free in DBD::mysql when using prepared statements

DBD::mysql is the perl DBI driver for MySQL and the primary way Perl applications and scripts access MySQL and MariaDB databases. The source repository is at https://github.com/perl5-dbi/DBD-mysql.

A vulnerability was discovered that can lead to a use after free when using prepared statements. This vulnerability is present in all releases at least back to versions 3.0 of the driver, which were released in 2005.

The CVE identifier for this vulnerability is CVE-2016-1251.

Version 4.041, including the fix for this vulnerability, is available on CPAN at https://metacpan.org/pod/DBD::mysql

Users of DBD::mysql with prepared statements are advised to patch their installations as soon as possible.

Many thanks to Pali Rohár for discovering and fixing the vulnerability.

The DBD::mysql maintainers, Patrick Galbraith Michiel Beijen

No Dist::Zilla

I guess it is the POD-pen now.

The third POD post in as many days and really noting to do with Dist::Zilla so I guess I will have to find some other pictures to post.

After yesterday's post I took some time and had a look at a large number of different CPAN modules to get some ideas on the contents and style of my Accessor POD.

One thing that I have seem many modules do is break their documentation into separate PODs, under the names-pace and I will do that with Accessor as well.

I am going to keep some things in the Accessor.pm proper as it is good to have some basic info present, most of the other items I have been working on over the past few days I think I will break into separate POD.

So here is the first draft (outline) of my documentation in all its glory by Names-pace

Database::Accessor

  • Abstract
  • Synopsis
  • Description
  • Getting Started
  • Resources

Shadertoy progress - playlists

The last two weeks, I didn't do much programming with OpenGL and GLSL. I used the weekend to catch up with some of the bug reports on Github and made the application more robust against missing input data or broken shaders. The net result is that it now can also cycle through a set of shaders:

MetaCPAN operational view

This is the third in a series of articles about MetaCPAN. The first article described the two main parts that make up the MetaCPAN project, the API and the search interface. The second article gave a high level summary of how the API uses Elasticsearch to hold and search information about CPAN distributions and authors.

In this post we'll look at how MetaCPAN links to other parts of the CPAN ecosystem, how the physical setup has changed with MetaCPAN v1, and another service that v1 has made available.

This post is brought to you by Booking.com, our second platinum sponsor. Booking.com is one of the largest Perl shops in the world, and have done a lot to support our community over the years. Thank you to Booking.com for supporting meta::hack.

WebService::Fake - but still usable!

I released a new simple module/application WebService::Fake and wrote about it in my main blog. I'd love to read any feedback providing any insight, negative included of course (provided they're honest and polite).

And oh! I really hope to see Learning Perl 6 spring to life! I opted for the "early versions" pledge because I'm too curious to see what it will be...

Dist::Zilla Goes to SKULE

Another boring day in the POD-pen

I am getting sick of writing up PO of well necessary evil I guess at least my post will be sort for the next few days.

Today I managed to get my methods and attributes all written up but that left me with a layout dilemma that I have to solve. Should I go with the very traditional POD alphabetical grouping like this

  • Methods
    • add_condition
    • add_element
    • add_filter
    • add_gather
    • add_link
    • add_sort
    • create
    • delete
    • new
    • retrieve
    • update
  • Attributes
    • available_drivers
    • conditions
    • delete_requires_condition
    • dynamic_conditions
    • dynamic_elements
    • dynamic_filters
    • dynamic_gathers
    • available_drivers
    • dynamic_links
    • dynamic_sorts
    • elements
    • ...

No need to put up all the attributes up there as the list goes on a bit.

At first glance it looks ok but if I was interested in the 'elements' attribute I would have to look in at least three different places to gather all the info I may need.

My present 'Elements' entry looks something like this

elements (RO) ARRAY-REF

An array ref of Element, Param, Function or Expression classes that are passed to the underlying DAD. ...

C::Blocks Advent Day 3

This is the C::Blocks Advent Calendar, in which I release a new treat each day about the C::Blocks library. Yesterday I showed how to get information across the boundary between Perl and C. Today I show how to do that for a number of types, including packed arrays, with minimal boiler-plate.

Meta::Hack - MetaCPAN Upgrade

A small group of us got together for a 4 day hackathon (17th to 21st of Nov 2016) in Chicargo, with the goal of switching https://metacpan.org over to the new https://fastapi.metacpan.org/v1/. This has been a massive project, upgrading our core backend from Elasticsearch 0.20.2 to 2.4.0. The project has taken over 2 and a half years to get to where we are now.

Oh, I should point out, day 2, we achieved our goal - after that we then fixed issues, added more features and made plans!

For MetaCPAN I take on a sysadmin style role, even though my in day job I'm manager / code reviewer mostly.

I had already set up Elasticsearch 2.4.0 on a cluster (we had the old version on a single node before!) and at Meta::Hack reviewed the configuration with Brad (seems I mostly got it right!).

Day -1 (on the plane)

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