Nick Sellen

My late 7th weekly update entry. Trip is ongoing.

This will be very minimal. I have no time to reflect right now!

My 6th weekly update entry. Trip begins!

My 5th weekly update entry. New Lanark, social.coop, Debt, Wobbly, 35c3…

My 4th weekly update entry. One day late this time. Maybe two by the time I’ve finished writing.

Lots on social.coop infrastructure, hosting my parents, …

Edition 3 of my weekly entries.

Moving into house, pondering about FareShare, bit of code stuff, buying a bike…

What I did last week

Visit foodsharing Edinburgh

I visited foodsharing Edinburgh and met up with Nicola Wilson from The Shrub Co-op. I hadn’t really planned what I was going to say, but gave a walk through of Karrot including how it works on the android app. I was pretty pleased with how it looked and worked :)

It seemed to fit their needs quite well - co-ordinating regularly scheduled pickups and recording the weight afterwards. At the moment they get people to sign up to a regular pickup, but that might just be because it is too hard to have a more dynamic structure - that’s something that Karrot allows more easily.

I have never been someone who is singularly focused on doing one thing really well. At various times I might feel admiration, appreciation, or jealously towards those people. It seems like it might be easier live like that and to know what to do at any given moment.

In any case, I am not like that. Maybe those people aren’t like that either.

At any one time there are many different directions that interest me - maybe I should work hard and save up some £££ so I can do some kind of project with it, maybe I should get more involved with existing initiatives that seem good and can use some of my skills, maybe I should find a bit of forest to live, maybe I should do more bike touring, walking, hitch-hiking, exploring, maybe I should finally leave the comforts of being in the first world, maybe I should stay in/near a city for long enough to get involved properly, maybe I should push to start a family, … I could probably go on.

I am liable to drift in between all of these things though, so want more tools to help that process.

I left this blog quite for a long time, I never really wrote much on it anyway. It was going to be for technical articles, probably to build my online presence as a computer programmer. It might still become that, but it will also be my general blog now too, where I write about my pondering, travelling, etc.

I also have my ponderings github repo, I am not sure how the content on these two sites should overlap.

Anyhow! I recently started nomadic bike touring again (nomadic meaning I don’t have a fixed base to go back to). I did this 5/6 years ago (see ontheroad.nicksellen.co.uk) and stopped because:

1. my money was decreasing, it clearly had an end, if not now then when…
2. I had a compelling offer to go back down south and do some work

Just a tiny script containing one sed command to escape input suitable for use with adb shell input text command.

#!/bin/sh
sed 's/\([`\(\)<>|;&\*\\~"'"'"'\$]\)/\\\1/g' <&0

Make it exectuable then move it somewhere on your path :)

Makes it possible to enter complex passwords for example. Example in combination with pass:

adb shell input text $(pass amazon | adb-escape-text)

For a recent project I was wondering what the best way to share node.js code across projects without publishing modules publically to npm.

The node.js ecosystem is all about sharing code publically and it’s super easy to do this entirely from the comfort of the command line with npm publish and friends. It’s quite a joy actually.

However, sometimes the code must stay private, but you still want nice modular npm modules. This scenario is less well supported by npm - npm themselves says:

Lots of companies using Node.js love the “many small modules” pattern that is part of the Node culture. However, splitting internal applications and private code up into small modules has been inconvenient, requiring git dependencies or other workarounds to avoid publishing sensitive code to the public registry.

Difficulties related this topic are well discussed:

• https://gist.github.com/branneman/8048520#comment-972519 - this is about 1.5 years worth of discussion on the topic, including some of the key node.js community
• http://injoin.io/2015/01/31/nodejs-require-problem-es6.html
• https://github.com/npm/npm/issues/7426

I actually found a solution pretty quickly that I’m happy with but I wanted to dig a bit deeper into the alternatives.

I was using Clojure to process github repos for use in libsearch.nicksellen.co.uk and ran into a problem. I had a function that was going through each repository and pulling out the useful information. This is quite time consuming as I use multiple API calls per repository and so I wanted to print some output to show progress.

The problem was that I was only seeing output printed after the entire operation had finished.

I'm quite new to Clojure and there are multiple things that might have been involved:

• Clojure uses lazy sequences in a lot of places - values are only calculated when needed
• in functional languages side effects are kind of special, and writing to stdout is a side effect
• I was running the code inside Emacs Live in a Leiningen REPL - that's a lot of layers in which to add behaviour

I've been working on a framework for building apps by describing them as a sequence of connected operations forming a graph. It's an early stage but reasonably functional. It's not publicly available at the moment.

It has some relationship to:

• Storm
• Flow Based Programming
• noflo.js

This is a quick overview of a few aspects of it.

For the next 10 days I’ll be somewhere in the Atlantic on this boat – Independent Voyager.

You can track it’s progress and see general details on the Marine Traffic website. Don’t worry if it disappears in the middle of the Atlantic, it doesn’t appear to track the boats all the way across.

The problem

Installing mysql2 (0.2.6) with native extensions /Users/nick/.rvm/rubies/ruby-1.8.7-p334/lib/ruby/site_ruby/1.8/rubygems/installer.rb:533:in `build_extensions': ERROR: Failed to build gem native extension. (Gem::Installer::ExtensionBuildError)

        /Users/nick/.rvm/rubies/ruby-1.8.7-p334/bin/ruby extconf.rb 
checking for rb_thread_blocking_region()... no
checking for mysql.h... no
checking for mysql/mysql.h... no
-----
mysql.h is missing.  please check your installation of mysql and try again.
-----

Ok, so we need the headers

Fortunately you can download MAMP source form their website - this gives you a .dmg with lots of .tar.gz files, you just need the mysql one.

I tried just copying the include directory as it was - but loads of the header files have variables that need replacing.

Let's compile this thing

compilation uses cmake, so ensure you have that first.

tar zxvf mysql-5.5.9.tar.gz
cd mysql-5.5.9
cmake .
make
mkdir /Applications/MAMP/include/
cp -r include/* /Applications/MAMP/include/
cp libmysql/*.dylib /Applications/MAMP/Library/lib

yay!

Installing mysql2 (0.2.6) with native extensions  
Your bundle is complete!

I don't often require this but always forget the command each time. Previously I had used:

pkgchk -l  | grep Pathname

...but whilst stumbling around I found the much more succinct (and undocumented as far as I can see):

pkgchk -L 

It turns out the nokogiri build script makes a few too many assumptions:

1. it tests for Solaris-ness by checking target_os is solaris2 where on Solaris 10 it is solaris2.10
2. it assumes gcc and sets a bunch of invalid CFLAGS such as -Wall
3. it doesn't let me specify a custom lib/include directories - it failed to find my iconv because of this (furthermore after adding the paths manually misleadingly it still said it couldn't find them but the problem was the options passed to cc were incorrect)
4. further down the line something decided it knew where Sun Studio was. It was wrong. to be fair this probably wasn't nokogiri's fault.

Update

I've ended up using gcc for compiling ruby related things which knocks out problems 2-4.

However I started seeing problems with a vasprintf symbol not found (similar to this problem). The problem is the same as my point 1 above (in ext/nokogiri/extconf.rb line:22):

elsif Config::CONFIG['target_os'] == 'solaris2'
  $CFLAGS << " -DUSE_INCLUDED_VASPRINTF"

should read

elsif Config::CONFIG['target_os'] =~/solaris/
  $CFLAGS << " -DUSE_INCLUDED_VASPRINTF"

For reference

# ruby -rrbconfig -e "puts Config::CONFIG['target_os']"
solaris2.10

Update 2

It's fixed by this commit

This is a quick roundup of the tools that can be used to extract text from PDFs or Word documents.

A common thing to expect from a web app is some kind of event feed:

peter liked your photo joe is also going to see blur next week your mum returned home

Another common thing is to receive emails when things happen:

your photo has been approved you are now friends with angie john sent you a message

I've noticed a few things have a similar pattern of working:

1. analyse environment and makes plans (logical orderly "left brain" thinking)
2. get immersed in immediate goal, following intuition along the way (more creative "right brain" thinking)
3. get lost or confused so goto step 1 (broken brain thinking)

• it actually works, yay!
• I appear to be able to cycle straight through buildings
• I can't cycle very fast
• this is a gross self inflicted invasion of privacy