While using AWS Lambda SAM Local to test Lambda functions locally, I encountered an error writing to the current directory where the function was running in the container (/var/task/). I’m not claiming a best practice of writing to the filesystem while running a Lambda function, but that’s part of my learning process for the moment, and I will investigate other workflows shortly. But what I was able to get working successfuly was writing to the /tmp filesystem instead of the current working directory.

Even if you’re not involved in the Python community, you might have heard about this security incident a while back. This is a not uncommon scenario where developers who may not be Github or distribution tooling (or security) experts make a mistake and breed mistrust in their project as well as the distribution medium itself.

But setting up your environment to prevent these accidental credential disclosures is easy to do, and will enhance your security posture.

Here’s another ‘for posterity’ type post.

I forgot I had configured my WiFi router to ignore certain MAC addresses and when I tried to put that machine on the Network today I had a rude awakening. Using the asuswrt-merlin firmware on my RT-AC66U router, I had configured things to allow 2 machines to be served DHCP from another PC so that I could run Cobbler on that machine and boot/kickstart these two hosts just by hitting the power button. But when I disconnected this Cobbler server at the beginning of my renovation, I forgot the MAC addresses were being ignored by the router.

I’ve been trying to learn more about AWS Lambda, at the same time learning some web development. For a newcomer to web application development, there is the question of whether you work on leveling up with traditional server based apps or “serverless”, aka FaaS, aka Lambda. I wanted to try converting a simple Flask app to Lambda, this is how I did it.

I spent a little time with Zappa today which is an AWS Lambda (aka “serverless”) framework for Python. Its not hard to create a very basic Flask application, then invoke Zappa to perform the many manual steps of creating a Lambda function, resulting in a URL where your application is running.

Another common error is that the docker daemon cannot connect to the outside world to download anything during build time. This can be corrected in a number of ways, but I have done it thusly.