Redis cache

April 10, 2019

I enjoy listening to podcasts, as they sometimes give me inspiration to create something. In one of the episodes of Python Bytes podcast guys mentioned https://github.com/bwasti/cache.py tool. cache.py allows to cache function calls across runs by using cache file. Simple and really useful.

This inspired me to write a similar thing but for distributed apps, based on redis as a cache storage. I called it rcache and you can find it on PyPI.

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Property based testing using jsverify

November 2, 2018

I wanted to write about property based testing for a long time. Since I usually write about things I have built, in order to write a post I had to built something. So I started building a runners calculator, using react-native. The calculator helps with estimating the pace (min/km) a runner needs to keep in order to finish by given duration.

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Cleaning up messy distributed logs, part 3

September 28, 2018

If you have been reading along it is my final part of this short story on cleaning up messy logs. I might write one on Kibana itself some day, as it is a difficult tool to use for a beginners. Previous parts of this story can be found here: part 1 and part 2.

This last couple of days at work I could spent more time on fixing logs as new project estimates has finished. Last thing I sorted was syslog parsing, with that done I could think on figuring out how to log tracebacks raised in our services.

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Collaboration of OAuth and LDAP

September 20, 2018

The goal

Almost everyone knows OAuth, it is widely used online and has a good reputation. In company where I work we have decided to integrate OAuth2 into our platform (based on microservice architecture, I'll be saying platform from now on). The trick was that it had to be integrated with existing LDAP server storing user data. User requesting the token had to input his LDAP username and password in order to receive the token. Looking for existing solutions was fruitless and new code had to be written. At that point I didn't know how this could be achieved. In addition to LDAP I had to use Django as a base of this for providing REST API endpoints. The limitations were clear at this point, risks were unknown. This is not an unusual thing when working as a programmer.

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Consumer with cache

September 10, 2018

Micro. Services. They are popular, and it is a pretty useful pattern if applied correctly. Using such pattern forces one to think a bit more when designing a solution to a problem. Not that it is more difficult but rather it is different. One of the main differences is communication or maybe data flow.

Regular applications tend to talk mostly by internal calls, or callbacks, which makes communication simpler. You do not have to care if function you are calling is available. If you pass correct arguments you will get a response. It is not that simple with micro services which in fact are like third party applications. They can go down, can throttle your calls, they can response with a delay, etc.

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