The Bookinfo application displays information about a book, similar to a single catalog entry of an online book store.
Displayed on the page is a description of the book, book details (ISBN, number of pages, and other information), and book reviews.
The Bookinfo application consists of these microservices:
* The productpage microservice calls the details and reviews microservices to populate the page.
* The details microservice contains book information.
* The reviews microservice contains book reviews. It also calls the ratings microservice.
* The ratings microservice contains book ranking information that accompanies a book review.
There are three versions of the reviews microservice:
* Version v1 does not call the ratings Service.
* Version v2 calls the ratings Service and displays each rating as one to five black stars.
* Version v3 calls the ratings Service and displays each rating as one to five red stars.
The end-to-end architecture of the application is shown below.
Figure 1. Bookinfo Application End2End Overview
To use the bookinfo application inside service mesh, no code changes are required. Instead an Envoy proxy is added as a sidecar container to all containers (product, review, details) which intercepts the traffic.
You can also access the Productpage in your browser. When you reload the page several times, you will see different results for the Reviews. This comes due to 3 different versions: one without any rating, one with black stars and one with red stars. http://${GATEWAY_URL}/productpage
The following 1-minute article is a follow-up to my previous article about how to use Keycloak as an authentication provider for OpenShift. In this article, I will show you how to configure Keycloak and OpenShift for Single Log Out (SLO). This means that when you log out from Keycloak, you will also be logged out from OpenShift automatically. This requires some additional configuration in Keycloak and OpenShift, but it is not too complicated.
I was recently asked about how to use Keycloak as an authentication provider for OpenShift. How to install Keycloak using the Operator and how to configure Keycloak and OpenShift so that users can log in to OpenShift using OpenID. I have to admit that the exact steps are not easy to find, so I decided to write a blog post about it, describing each step in detail. This time I will not use GitOps, but the OpenShift and Keycloak Web Console to show the steps, because before we put it into GitOps, we need to understand what is actually happening.
This article tries to explain every step required so that a user can authenticate to OpenShift using Keycloak as an Identity Provider (IDP) and that Groups from Keycloak are imported into OpenShift. This article does not cover a production grade installation of Keycloak, but only a test installation, so you can see how it works. For production, you might want to consider a proper database (maybe external, but at least with a backup), high availability, etc.).
During my day-to-day business, I am discussing the following setup with many customers: Configure App-of-Apps. Here I try to explain how I use an ApplicationSet that watches over a folder in Git and automatically adds a new Argo CD Application whenever a new folder is found. This works great, but there is a catch: The ApplicationSet uses the same Namespace default for all Applications. This is not always desired, especially when you have different teams working on different Applications.
Recently I was asked by the customer if this can be fixed and if it is possible to define different Namespaces for each Application. The answer is yes, and I would like to show you how to do this.
Classic Kubernetes/OpenShift offer a feature called NetworkPolicy that allows users to control the traffic to and from their assigned Namespace. NetworkPolicies are designed to give project owners or tenants the ability to protect their own namespace. Sometimes, however, I worked with customers where the cluster administrators or a dedicated (network) team need to enforce these policies.
Since the NetworkPolicy API is namespace-scoped, it is not possible to enforce policies across namespaces. The only solution was to create custom (project) admin and edit roles, and remove the ability of creating, modifying or deleting NetworkPolicy objects. Technically, this is possible and easily done. But shifts the whole network security to cluster administrators.
Luckily, this is where AdminNetworkPolicy (ANP) and BaselineAdminNetworkPolicy (BANP) comes into play.
Lately I came across several issues where a given Helm Chart must be modified after it has been rendered by Argo CD. Argo CD does a helm template to render a Chart. Sometimes, especially when you work with Subcharts or when a specific setting is not yet supported by the Chart, you need to modify it later … you need to post-render the Chart.
In this very short article, I would like to demonstrate this on a real-live example I had to do. I would like to inject annotations to a Route objects, so that the certificate can be injected. This is done by the cert-utils operator. For the post-rendering the Argo CD repo pod will be extended with a sidecar container, that is watching for the repos and patches them if required.
Thomas Jungbauer
( Lastmod: 2024-05-05 )
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2 min read
Figure 2. Bookinfo Application