caelumvox - building on a cloud

The SOLID software design principles weren't called SOLID while I was in grad school, but the concepts were there in my Object Oriented Design course. They're worth mentioning here, primarily because I think once you start coding and become dangerous, it's one of the best ways to stay organized once you incorporate it into your daily coding routines, and it even changes your way of thinking for the better: https://en.wikipedia.org/wiki/SOLID

As part of a series of projects I'm putting together in an online portfolio, I created reveille (reveille.caelumvox.com) , a website that shows articles of local websites inserted by an AWS Step Function job whose lambdas scrape the website and load it into a MariaDB instance. Some details: The Step Function Lambdas are written in Python, The backend API is written in the Express Node Framework, The frontend app is written in the Angular Node Framework using bootstrap for frontend styling and placement for desktop and mobile browsing. To keep costs low, the frontend, backend, and database are all hosted on one EC2 instance. The frontend and backend are hosted by the same nginx container with a Let's Encrypt certificate. I also created a home page at caelumvox.com as a starting place for visitors, but it still needs a bit of work. The site is hosted on an AWS Cloudfront distribution. HTTPS only!

I was interested in hosting a small portfolio of applications in AWS, but I wanted to keep costs down.  I was willing to maybe host about $30-$40 a month of servers just to showcase some of the applications I was putting together.  Here's what I came up with. The basic capabilities here were: serve up about 6-10 applications that would require some level of web application hosting, database, file storage for larger items, and possibly queuing or email schedule jobs to run periodically to either scrape websites for new data or access APIs regularly These were the services in mind, all out of US-East-1 (Virginia): EC2 instances are pretty cheap.  You can run a t3a.nano for about $3.38 a month, or a t3a.micro for about double that for $6.77.  The more things can run on one of these instances, the better. Lambdas also don't really add up to much if they are scheduled jobs that do not consume large amounts of memory or computing.   The cost of a Lambda run as part of an API gateway

While in the past I've held a pretty high opinion to using mercurial for version control, the majority of version control these days seems to done in git.  Here were the commands I found most useful to get productive with git right away. # Clone a repository from an origin, i.e. my github MaskingUtils repository git clone git@github.com:caelumvox/masking-utils.git # Add a file after it's been updated to stage it for commit, or add a new file git add filename # Commit the file to local repo git commit # Push the file to the origin so the rest of the team can see it git push # List all locally tracked branches git branch git branch --list # Get a list of all branches from the remote git branch -r # Create branch locally git branch develop # Push the branch to the origin repository to make sure it is tracked there git push --set-upstream origin develop # Pulls latest from all local branches tracked from origin; won't pull non-tracked branches git pull --all # Fetch the branch

As the push for serverless applications moves on, I was curious as to which languages were best suited for serverless execution: https://epsagon.com/blog/aws-lambda-programming-language-comparison/ Not surprisingly, Java and C# don't seem like such a great fit due to their cold-start latency, which is something I've noticed with Lambdas in AWS in the past.  If you want a quick response to a serverless request (such as API requests), probably something like Golang, Python, or Node.js are the way to go; C# and Java should probably be saved for jobs not requiring immediate responsiveness.

Really, I haven't posted in 9 years? Much has changed since 2011; mobile, cloud, and social are all really huge, and I've definitely had a large focus toward these. I hope to write shortly about things I've learned and wish to share in the coming weeks and months, and hopefully do better at maintaining this site a little better than before.