TPDP Episode #14: Object Storage for Application Developers

I am pleased to announce that the latest episode of The Polyglot Developer Podcast is now available to download from all the popular podcasting networks. In this episode titled, Object Storage for Application Developers, I’m joined by Krishna Srinivas from Minio to talk about what object storage is and the various solutions that are available.

Episode #14 can be downloaded for free from iTunes, Pocket Casts, and every other popular network, but it can also be heard below.

Remove Untagged Docker Images From Your Docker Host Via The CLI

If you’re like me, when it comes to Docker, you probably build images non-stop. I must admit that when I create images, I don’t create any special tags, even though I should. Instead every build uses the latest tag because that is enough to meet my needs. Regardless of what tags you use, you may find yourself building the same thing over and over. When this happens, the previous image remains on your machine, but becomes untagged to make room for the new build.

So how do you prevent having potentially hundreds of untagged Docker images lingering on your machine? We’re going to see how to quickly remove them.

Create A Raspberry Pi Cluster With Docker Swarm And Raspbian Linux

Back when I was first learning about Docker, I had tried to use it on one of my Raspberry Pi devices. This was when Docker had first become available officially for Raspbian. When I was playing around with Docker and my Raspberry Pi, I had written a tutorial for deploying containers, or more specifically a Ghost container. This was a single container on a single device or node. Since then I started playing around with Docker Swarm and decided to create a Raspberry Pi cluster.

We’re going to see how to take several Raspberry Pi devices, cluster them using Docker Swarm, and deploying containers to Swarm with replica copies.

Bulk Remove Unconfirmed Sendy Subscribers After A Certain Number Of Days

You may or may not know this, but I use Sendy to send out my monthly newsletters because it is incredibly cheap in comparison to competitors like Mailchimp. Anyone who has done list building before knows that over time you’re going to end up with a lot of stale subscribers that need to be cleaned in an effort to save space and keep things organized.

My email lists require a secondary opt-in to prevent SPAM subscriptions. The problem with this is I still get a lot of SPAM subscriptions even if they are never included in my newsletters. These subscriptions have no business being in my list, so it is best to remove them after so long.

We’re going to see how to use SQL to remove unconfirmed email subscribers in Sendy after so many days.

Load Balancing A Docker Swarm Cluster With An NGINX Reverse Proxy

If you’ve been working towards containerizing your web applications like I have, you might be at a point where you’re ready to start clustering your containers. Previously I had written about creating a container cluster with Docker Swarm and using NGINX as a reverse proxy for a few containers. The catch here is that neither of these previous tutorials were meant to work together. In the previous example we were using a reverse proxy for containers on a single server. While Docker Swarm offers it’s own load balancing, you’ll find it makes sense to have NGINX as well because not every container can run on the host as port 80.

We’re going to see how to create two service containers that are replicated across several nodes. These services will be a simple Apache and NGINX web applications. Then we’re going to throw an NGINX reverse proxy into the mix that keeps track of the upstream nodes for its own load balancing.

Using The Docker Client With A Remote Machine Or Virtual Private Server

Not too long ago I wrote about containerizing a bunch of web applications and putting them behind an NGINX reverse proxy. This is because I’ve been exploring the possibility of taking all my personal applications and turning them into Docker containers for easy maintenance and portability. I currently use Digital Ocean and if I had to guess, I’m going to be using it for a lot longer as it is a great service. So what does it take to get containerized applications on Digital Ocean or any other remote machine?

We’re going to take a look at creating and defining a remote machine in Docker and deploying containers on it.

Using Couchbase With Docker And Deploying A Containerized NoSQL Cluster

You can do a lot of cool things with Docker, for example containerizing web applications, processes, and a bunch of other things. What happens when you want to deploy your database as a container, or more specifically, your distributed database as containers? Most NoSQL databases are distributed, meaning they can be easily clustered with data replication and a bunch of other awesome features. How do you provision each node or configure the cluster?

We’re going to see how to create a custom Docker image for the popular document-oriented NoSQL database, Couchbase, and cluster a few containers together to make one awesome NoSQL cluster.