Over the past year, my team has been making the transition from Flask to aiohttp. We're making this transition because of a lot of the situations where non-blocking I/O theoretically scales better:

• large numbers of simultaneous connections
• remote http requests with long response times

There is agreement that ...

An interesting problem arose at work today, regarding how to build an aggregate of changes to a MongoDB collection.

A more general version of the problem is:

1. you have a document which has multiple buckets it could belong to. Say, an animal which an arbitrary set of tags, such as ...

Introducing deepmerge. It's a library designed to provide simple controls around a merging system for basic Python data structures like dicts and lists.

It provides a few common cases for merging (like always merge + override, or raise an exception):

from deepmerge import always_merger, merge_or_raise

base = {
    "a": ["b"],
    "c": 1 ...

If you've worked with tornado, you may have encountered a traceback of a somewhat bewildering error:

Traceback (most recent call last):
    File "/usr/local/lib/python2.7/site-packages/tornado/ioloop.py", line 832, in start
fd_obj, handler_func = self._handlers[fd]
KeyError: 16

A few other people have been confused ...

In 2016, I bought a Steam Link, allowing me to play games on my TV without having to lug a whole physical machine over. The main requirement of Steam Link is the link and the PC on the same network: this allows encoded streaming from the PC to the link ...

A majority of my career has been spent on building web services in Python. Specifically, internal ones that have minimal or no UIs, and speak REST (or at least are rest-ish).

With each new service, I found myself re-implementing work to make user-friendly REST APIs:

• validation of incoming data, and ...

As of December 2016, Flask has a built-in logger that it instantiates for you. Unfortunately, this misses the errors and other log messages in other libraries that may also be valuable.

It would be nice to have a single logger, one that captures BOTH library AND app logs. For those ...

One of the most interesting artifacts of most programming languages using English conventions is variable naming. Today I contend that:

When it comes to reaching language proficiency, vocabulary is important. To reach proficiency as quickly as possible, the choice of vocabulary is important.

I'm going to explain my approach a bit.