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#!/usr/bin/env bash

# TODO

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Pods, services, deployments... it all sounds the same until you've had the chance to get hands on with it. This will be a short reference to the terminology of Kubernetes resources for a new cluster operator or developer.

Pods

Pods are one or more containers (but usually just one) running together; they are the smallest executable resource in Kubernetes.

Do not use pods directly, they don't scale and cannot be relocated to a different server. Use one of the below abstractions to manage templates of pods.

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1. Kubernetes is not the solution to every problem.
2. Kubernetes just runs containers.
3. Kubernetes shall not manage the persistence layer; prefer hosted services.
4. Kubernetes Manifests shall be heavily commented to explain cryptic and non-standard usage.
5. DevOps shall provide a service layer (the Cluster Platform) to improve application visibility.
6. DevOps shall provide training, documentation, and guidance to Developers learning Kubernetes.
7. DevOps shall seek to minimize the amount of YAML required to write and maintain Kubernetes Manifests.
8. DevOps and Developers shall share the burden of maintaining business layer applications.

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$ psql -U postgres -h localhost
psql (11.4, server 9.6.13)
Type "help" for help.

postgres=> \l
                                                List of databases
     Name      |       Owner       | Encoding |  Collate   |   Ctype    |            Access privileges
---------------+-------------------+----------+------------+------------+-----------------------------------------
 cloudsqladmin | cloudsqladmin     | UTF8     | en_US.utf8 | en_US.utf8 |
 destination   | postgres          | UTF8     | en_US.utf8 | en_US.utf8 |

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Ingress

Background

Every resource type within Kubernetes is managed by a "controller", an application running a watch loop and reacting to changes to the resource it's watching. The controller-manager runs and manages all the built-in controllers, but additional resources (e.g., CRDs) require user-deployed controllers.

Ingress resources are an interesting example, as they're a (the only?) built-in resource type without a built-in controller. Instead Kubernetes distributions often package an ingress controller for their cloud platform (e.g., gce-ingress). By themselves ingress resources are meaningless; it's only that separate ingress controller that makes them real within a cluster.

How It Works

An ingress controller monitors ingress resources for changes (incl. creations and deletions) and up

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To reproduce the issue:

• Serve script.js and index.html with a simple HTTP server.

$ python3 -m http.server

• Ensure your ad-blocker is disabled and navigate to any page on www.ralphlauren.com. I was able to reproduce the error in Firefox and Chrome.
• Run bookmarklet.js either as a bookmarklet or in the browser url.
• The iframe created by script.js sends a message to a listener in index.html once, then is hammered with additional events (due to the bug) with data similar to "{"cxr":true,"id":"de358f9-93588236-068e-9f0c-fe732…le-frame'][1]"],"sid":"7_","sp":{"x":0,"y":6610}}", all of which are logged to the console.

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