usefulContainers

Contains containers useful for testing and learning exercises.

meuApache

This is just Apache httpd, but it listens on port 9000 and it shows a one-liner greeting. It is meant to test containers and container orchestrators. You launch it with a given name and port, then try to reach it.
As of now it only listens in port 9000. But I plan to make that a parameter.

To run it as a standalone docker container: docker container run --rm --network=host --detach jrkessl/meuapache

meuCurl

Just a simple container that extracts a webpage from a parametized URL and port, outputs it to the std output, then exits.
Useful for testing network connectivity, and network routing when learning container orchestrators: launch a webpage somewhere with some port, and use this container to try to reach it.
You may be thinking "I can just run curl in my prompt, why do I need this" but think you want to test container to container communication, and not host to container communication.

Run as: docker container run --rm --env HOS=localhost --env POR=9000 --network=host jrkessl/meucurl

variableSpitter

This container:

• Retrieves and prints out environment variables that are reachable to the container
• Possibly other variable-related test or exercise, to be added...

Building:
docker build . --tag variablespitter

Using it:

• Spitting a variable with docker CLI:
  docker run --name varspit --rm --env var1=valueGoesHere jrkessl/variablespitter:latest
• Spitting a variable with declarative Kubernetes: just check the file 'variableSpitter.yml' and apply with kubectl apply -f variableSpitter.yml and then kubectl logs pod/<pod name goes here>

postgres

This contains a walkthrough of using PostgreSQL with Kubernetes.
Check instructions in the file. Here you have:

• Commit 51682752fde1f373317914fe6b0319cc6646a9f0: this just creates a Postgres deployment with declarative yaml.
• The latest commit: adds a demonstration of using local persistent volumes (hostPath type) so that the database's data survives its Deployment.