Lightning Talks Day 2

Django and robotic telescopes

Edward Gomez http://lcogt.net

• Galaxy pictures - pretty
• 12 telescopes currently operating “the sun never rises on our telescopes”
• telescopes size of double decker bus, family car, R2D2 - clusters
• 1000 ish active users (250 astronomers, 750 school kids)
• web requests to server, then telescopes controlled
• django to take requests, schedule optimiser, save results
• image pipeline, python archive, served by django
• try it, http://bit.do/lco-dj-signup
• work on it http://lcogt.net/jobs

Real time web thing

Craig Stone

• slides not working
• mashing django and angular
• django-angular and djangular
• use {% verbatim %} tag around angular framework

API by example

Carlos Barrobes @technomilk

• an approach to testing across services
• before - single app
• want to split it up
  • UI in angular
  • backend in django/DRF
• want both teams to work independently
• want each part to be tested separately
• backend team should not dictate the API
• ABE - API by example - in json files
• 3 repos - backend, client, mocks
• all begins with pull request to the mocks repo
  • signed off by at least one person from each team
  • PR is documented discussion
  • ABE files is documented API
• ABE mocks are versioned dependency for both front and back end

https://github.com/txels https://github.com/apibyexample

git-crypt

Thomas github.com/alphacc slides - https://github.com/alphacc/djangoconeu2015

• admins have secret in git, but other users can’t read secret
• transparent encrypt/decrypt when check in/out
• you need a GPG key
• brew install git-crypt
• git-crypt init /path/to/key
• files to encrypt in .gitattributes *.key filter=git-crypt diff=git-crypt

http://www.theport.ch http://www.theport.ch/portfolio-item/the-port-presentation

Using StreamingHTTPResponse for JSON & HTML

Matthew Somerville @dracos

• stop your server falling over with hacks and bug fixes
• request for every map boundary
• started 50M, 500M looksup ... total almost 2G
• was loading it all into memory - should have been using StreamingHTTPResponse
• then had to sort out middleware ...
• but we’re not doing a generator, but was using a dictionary
• created iterdict - not really a dict, but allows generator
• new total 215 MB
• gzip with unicode caused death
• HTML version - django doesn’t stream templates, so had to iterate django template
• jinja2 does support iterating template

shakeslide - Predicting landslides

@DrRobParker @g...

• Geologist at Cardiff Uni
• using Django to predict landslides triggered by earthquakes
• building a global db of landslides
• then using machine learning, models, ... for prediction
• then made website doing near real time prediction - shakeslide
• Nepal - predictions made - huge areas, real risk
• landslide dams - landslide blocks river, water builds up, bursts -> massive damage
• built 2 worker profiles
• 1 is data source provider - constantly updating
• queuing system
• 2 renders hidef images

BDD with goat

Ilja, cuescience slides and code - https://github.com/cuescience/djangocon2015-goat

• BDD - behave lib - test written in natural language
• type annotations - use python 3 - but types specified twise
• goat is addon to behave - can then use python 3 function annotations
• context is repeated a lot - do implicit argument injection
• pip install goat