on web development.
Yay. I have made it to PyCon UK again this year.
I’m starting on day 2 this year but still glad to be here.
As usual the friendly Python community are making everyone feel welcome.
I shall be posting notes and tips I pick up over the next few days.
Visit the conference site for more information about PyConUK.
Look out for the video uploads of the talks post conference too.
I really enjoyed refreshing my Scrum practice, when I recently attended Scrum master training with Paul Goddard from Agilify. Below is a quick overview of Scrum.
Scrum is an Agile framework for software development.
The ability to respond to change and deliver useful quality products quickly through incremental development and client participation.
Scrum makes use of…
Cross skilled self-organising groups that work at a sustainable rate.
This leads to my favourite outcome:
Sane happy people make nice code!
Scrum has a manifesto of core principles which I will paraphrase below as:
This role is to facilitate and coach the team. To assist in the application of the Scrum framework. As teams are self-managing, this role must support the group developing the product not dictate to the team nor assign tasks.
Essentially the client. Scrum relies on strong client participation, co-locating with the team. Continual prioritisation of tasks and feedback help to deliver a relevant product and high customer satisfaction.
The doers – makers, fixers, testers, designers, sysadmins, developers, … Scrum teams tend to be made up of between 4 to 9 people. Smaller teams are more likely to suffer from a lack of a range of skills.
Starting with a short fun overview of key Scrum concepts – muppets included.
Scrum for Schmucks https://www.youtube.com/watch?v=oJV-kgj4m68&feature=youtu.be
Learn about Scrum https://www.scrumalliance.org/why-scrum
What is Scrum https://www.scrum.org/resources/what-is-scrum
R – an interpreted programming environment for statistical computing and graphics
Coming to R from Python and other programming languages, my notes are comparative versus exhaustive. See the following for a good guide.
There is a mechanism for installing R local packages (akin to the usage of virtualenv for isolated Python package installations)
install.packages
Lists are like dictionaries
$ is a key (like [‘sfsf’] or dot)
data.frames are like pandas
dot just a naming convention
<- and <= assignment
Speed tips:
Vectorise (map/reduce like functions) vs looping in r
Can easily import/export CSV
Space tip – If you need to store large amounts of data, consider using binary vs ASCII or other plain text files.
Can access DBs directly, using data frames
Note to self, look up NETCDF (commonly used as a climate data format)
Nice built in datasets
Very easily generate charts and save the output to jpeg, pdf, etc. See for more options:
Loving the application installer extension to homebrew OS X package manager – http://caskroom.io/
I’m lucky enough to be attending DjangoCon Europe this week. See the schedule of talks for a teaser. Talks are all being videoed and transcribed and will be shared online soon.
My thoughts and fairly rough notes to self can be found below:
This speacker was very encouraging of welcoming new members to the community
Look up PyCON INC?? Pixy dust workshops? Must have misheard this but there is another group akin to django girls
Uses some Erlang – load sensitive
Dealing with fluid requirements
Over engineering upfront to be very modular can lead to issues with referencing other apps
Instead incrementally creating new apps from the initial app.
Grow in a tree like structure, app at a time.
Aim – when you add new feature only need to touch one app
They use a services layer – found idea on stackoverflow article – look up seemed to work for them.
Sounds like their project could be on the scale of BOS codebase.
She thinks services and unit tests first, end user HTML later.
Q: A repo per app
A: Same repo for all the apps
Snakes and rubies convinced him to go down the Django vs Ruby path.
Use of clis
See slide that covers principals he brought into place in his team.
Daniele puts out a call to assist with sprint to develop something for the Cardiff Wellbeing centre. They are volunteering and offering free 25 minute counselling sessions slots to attendees.
Lots of experience creating Django admin interfaces. Jokes about leaving PHP behind.
Discusses how the admin site is wired together
Useful overrides for admin site:
Ola’s favs:
Don’t use list_editable as not currently multi user safe way of editing your database.
ChangeList – if overriding here, maybe you are in too deep
Tips & tricks:
Advanced permissions
method overrides used to achieve permissions for DjangoGirls websites
Customising changelist
Additional annotations for attributes/properties that appear on changelist.
She wants to see updates to django admin area
Supporting django-flat-theme – updated CSS mainly
Ola wishes admin components were more reusable
Lecturer
Font has held Mathematics back from exploding on the web.
Can we do something with Latex and eLearning
Will unicode come and save us in the end ;)
MathJax is a revolution. Javascript, accessible browser rendering of Mathematical symbols
https://github.com/mathjax/
http://docs.mathjax.org/en/latest/glossary.html#term-mathml
Describes a very interesting start of a Maths VLE.
MathML – not human readable
Django core committers fielded IRC style questions from the audience
Spoke about the importance of bringing humanities students along with digital/programming movement.
Made an interesting point about the lack of non mathematical examples when demonstrating coding constructs. e.g frequent citations of coding the Fibonacci sequence.
Mentioned a good resource aimed at non programmers, Hello web app.
Introduced Salt terminology and showed some basic Salt commands.
Presentation tip: Use Ctrl + L to move cursor to be shown at the top of the terminal window
Salt allows you to add breakpoints
salt-cloud – provision AWS etc
mines are data stores
He co-wrote the book High Performance Django
There is talk of hpd-states
Tips:
pytest-cache --lf run the last test that failed
You can decorate with parameters to re-run the test with different variables
When even Google cannot help you. Mishearing jungle parler will not help you search for the django parler internationalisation egg ;) Context helped me decode viable to mean variable a lot sooner ;)
why use py.test?
Look out for slide notes – he was very keen on py.test and was using it at Mozilla.
Look into the cricket test tool
Walked through an example of a PHP script that he found online that had huge security issues.
He developed an online tool to check security configuration of a django site
All related to prefixed SECURITY_ settings.
Recommends book: Bulletproof SSL and TLS
Remember to test for unexpected cases. e.g not just test for logged in user, test when not logged in too.
Check out requires.io – tracks the releases of your dependencies
@erikpub
An almost poetic call to embrace life and do more with our ability to change many lives.