Create PDF files from Markdown sources in OSX

Create PDF files from Markdown sources in OSX

When Markdown appeared more than 10 years ago, it aimed to make it easier to express ideas in an easy-to-write plain text format. It offers a simple syntax that takes the writer focus away from the formatting, thus giving her time to focus on the actual content.

The market abunds of editors to be used for help with markdown. After a few attempts, I settled to Sublime and its browser preview plugin, which work great for me and have a small memory footprint to accomplish that. To pass the results around to other people, less technical, a markdown file and a bunch of images is not the best approach, so converting it to a more robust format like PDF seems like a much better choice.

Pandoc is the swiss-army knife of converting documents between various formats. While being able to deal with heavy-weight formats like docx and epub, we will need it for the more lightweight markdown. To be able to generate PDF files, we need LaTeX. On OSX, the solution of choice is usually MacTeX.

Setup Pandoc for document conversion

Choose the easy brew way:

$ brew update
$ brew install pandoc

If the above solution is not working, the alternative is to take the cabal route:

$ brew install ghc cabal-install
$ cabal update
$ cabal install pandoc

For those interested, the install page covers each aspect in more depth.

Setup Mactex for PDF generation

$ brew tap phinze/cask
$ brew install brew-cask
$ brew cask install mactex

Generating PDF files

We will use the current article as the example we want to export as PDF. The markdown source is available as a gist.

When trying the output command from the pandoc documentation, we notice there is a problem, as it can’t find pdflatex.

$ pandoc -o out.pdf osx-pdf-from-markdown.markdown
pandoc: pdflatex not found. pdflatex is needed for pdf output.

Let’s check it’s been properly installed and symlink it correctly.

$ ls -lsa /usr/texbin/pdflatex
$ sudo ln -s /usr/texbin/pdflatex /usr/local/bin/

Re-running the output command works correctly and gives us a shiny new PDF file.

$ pandoc -o out.pdf osx-pdf-from-markdown.markdown

Create Beautiful UML Diagrams in Minutes from the JetBrains IDE

A few days ago I needed to assemble together several disparate pieces of information about the current project. Our technology stack is complex, and people have different backgrounds, so I realised that a visual representation in UML would be the best fit.
The current article details how to prepare a working environment using Graphviz and PlantUML in PHPStorm, then goes through the process of creating a simple sequence diagram to use them.

Diagrams: the “why” and the “how”

Created by the Object Management Group, UML is the de-facto standard design language in the software community. If you are not familiar with it, or just need a quick refresher, this article on the developerWorks website is very good.

As I tried a couple of online services, it became increasingly clear that they were not fit for my complex set of interacting components. I then turned to my favorite diagramming, tool Graphviz. It turned out there was no straightforward editor on top of it to do sequence diagrams. Luckily, I pretty quickly found PlantUML, which uses Graphviz for all it diagrams but sequence ones. I was impressed by the amount of integrations it offers so I decided to give it a try, and was amazed with the speed of which I produced the end result.

In the next sections we’ll learn how to get our environment up and running, and then draw a quick example sequence diagram.



Installing Graphviz using brew worked perfectly for me.

$ brew install graphviz

If you prefer an alternate method, you can download the package instead.


Internally, our company uses PHPStorm as an IDE for developing PHP code, and IntelliJ idea for the Java bits. I will present details for the PHPStorm users, but the steps should be easy to replicate in other IDEs of the same vendor.

Let’s open the preferences and start looking for new plugins.


We need to search for “PlantUML” and install it.


After restarting the IDE, we notice there are new filetypes available for us to create:


Sequence Diagram example

Let’s create a new UML Sequence diagram, named “demo”. Notice how the .puml extension was automatically added.


The diagram I actually needed to produce is very heavy, and not fit for the purpose of this quick introduction. Then I remembered checking the Clean Coders Yahoo group the other day, and found some Ruby sourcecode they were talking about. I thought it would be a good example to try our new diagram superpowers on, as it’s short.

The first step is to define the participants in our diagram. It’s easier to list them all in the beginning, because this way we can choose the order in which they appear.


We will now add the sequence of events. The PlantUML website has a great page on the various options available, so make sure to check it out.


The stock look and feel is nice and gets us far. I however felt the need to prettify the end result by introducing some nice formatting options. The manual page for the skinparam command is very helpful.



After installing Graphviz and PlantUML extension for PHPStorm, we were able to produce a sequence diagram in a few minutes. You can take a look at the final version of the code as we obtained it. The advantage of having these tools available straight from the IDE is that the diagrams can be part of the project code, and be managed together.

HowTo Quickly Erase All Documents from an ElasticSearch Index

Let’s say you are locally developing things using the amazing ElasticSearch technology, and would like to quickly wipe out all documents from a specific index.

Assuming you have ES installed on localhost, and the index name is playground, here’s how you would do it:

curl -XDELETE 'http://localhost:9200/playground/?pretty=true'

And the index is now empty, waiting for test data!

Fix Vagrant problems after Mavericks update

Updated the OSX to 10.9 over the weekend.

While most of the troubles I encountered were caused by PHP 5.3 being completely wiped out and the system getting a stock install of 5.4, there were other minor things which didn’t go quite smoothly.

I use a VirtualBox + Vagrant + puppet combination to work on some side projects, and this was affected in a pretty mysterious way, as can be seen below:

➜  centos64 (master) ✗  vagrant up
Bringing machine 'default' up with 'virtualbox' provider...
[default] Importing base box 'theCentos64'...
[default] Matching MAC address for NAT networking...
[default] Setting the name of the VM...
[default] Clearing any previously set forwarded ports...
[default] Creating shared folders metadata...
[default] Clearing any previously set network interfaces...
There was an error while executing `VBoxManage`, a CLI used by Vagrant
for controlling VirtualBox. The command and stderr is shown below.

Command: ["hostonlyif", "create"]

Stderr: 0%...
Progress state: NS_ERROR_FAILURE
VBoxManage: error: Failed to create the host-only adapter
VBoxManage: error: VBoxNetAdpCtl: Error while adding new interface: failed to open /dev/vboxnetctl: No such file or directory

VBoxManage: error: Details: code NS_ERROR_FAILURE (0x80004005), component HostNetworkInterface, interface IHostNetworkInterface
VBoxManage: error: Context: "int handleCreate(HandlerArg*, int, int*)" at line 68 of file VBoxManageHostonly.cpp

This was not an easy task to fix, as Mavericks is pretty new, and Google doesn’t help very much with finding the solution.

In my case, I discovered that if I restarted VirtualBox things will be working again.

sudo /Library/StartupItems/VirtualBox/VirtualBox restart

So this is not strictly related to Vagrant itself, rather to the VirtualBox provider I was using.

HowTo Easily Upgrade Ruby on Mountain Lion

The default Ruby version coming with Mountain Lion is a bit old
➜  ruby -v
ruby 1.8.7 (2012-02-08 patchlevel 358) [universal-darwin12.0]

If only for staying up-to-date with the latest Ruby version, you will want at least 1.9 on your local machine.

There are multiple ways to achieve this, but I found it easiest to use the Ruby Version Manager. This clever command-line tool gives you the freedom you want, at a minimal cost.

Let’s start by installing it:

➜ curl -L | bash -s stable --ruby

At the time of this writing, the latest Ruby version was 1.9.3, and RVM already installed it on your machine.

All you need to do now is to type
➜ rvm use 1.9.3
➜ ruby -v
ruby 1.9.3p385 (2013-02-06 revision 39114) [x86_64-darwin12.2.1]

In case you will need to return to the default ruby version, this is easily accomplished by
➜ rvm system

The screencast has even more detailed RVM usage, geared towards developers.

Easy Setup of Sencha Command on Your Mac

Prerequisite: If you haven’t done this already, setup Sencha Touch SDK.

Step 1: Download Sencha Cmd from the dedicated page.

Download latest Sencha Cmd from the website


Step 2: Move the archive to a working folder. I used ~/Documents/Work/learn/sencha.

Step 3: Unpack by double-clicking it. You should find the installer in your working directory, like in the picture below.

Step 4: Launch the setup by double-clicking the installer. Proceed to the next step. Accept the license agreement and click Next once more.

Make a note of the installation folder you choose in this step. I used /Users/g/bin. Proceed to the end of the wizard and click Finish.

Step 5: Verify that everything went okay. This is achieved from the command-line, by navigating to the SDK setup folder and launching the sencha command.

Note 1: The Sencha Cmd installer automatically adds its dependencies to the .bashrc settings file. if your favorite shell is not bash, you need to perform an extra-step before the verification works. If you’re a zsh user like me, at the end of your .zshrc file you need to add 2 lines to make this work.

export PATH=/Users/g/bin/Sencha/Cmd/$PATH
export SENCHA_CMD_3_0_0="/Users/g/bin/Sencha/Cmd/"

Don’t forget to reload the settings file:

. ~/.zshrc

Note 2: If you had previous versions of Sencha installed, it’s a good time to cleanup your .bashrc (or .zshrc) file from those occurrences.

Easy Setup of Sencha Touch SDK on Your Mac

Step 1: Go to the download page of the Sencha Touch product.

In the Free Commercial Version form, enter your email address and click the Download button.

At the time of this writing, the latest stable SDK version is 2.1.1, which you will find referenced in the paragraphs below.

Step 2: Click the download link in your email. This will open a browser window and start the sdk download process. The result should be a file in your Downloads folder.

Step 3: Move the sdk archive to a working folder. I used ~/Documents/learn/sencha/ as the final destination.

Step 4: Unarchive the sdk. This should create a folder ~/Documents/learn/sencha/touch-2.1.1 on your machine.

That’s it!

Now, when you see instructions on the Sencha documentation that look like

#  Make sure the current working directory is the Sencha Touch 2 SDK
cd /path/to/sencha-touch-2-sdk

you will need to do use the path obtained in step 4 above. In my case, this means:
cd ~/Documents/learn/sencha/touch-2.1.1