Merge branch 'developer-docs-dev-env-sso' into 'master'

SSO testing with k3d environment

See merge request platform-one/big-bang/bigbang!1149

docs/developer/development-environment.md

@@ -416,6 +416,29 @@ sudo vim /etc/hosts
           and select SOCKS v5
       1. Select ```Proxy DNS when using SOCKS v5```
 
+7. To be able to test SSO between BigBang Package apps and your own Keycloak instance deployed in the same cluster you will need to take some extra steps. For SSO OIDC to work the app pod from within the cluster must be able to reach ```keycloak.bigbang.dev```. When using a development k3d environment with the development TLS cert the public DNS for ```keycloak.bigbang.dev``` points to localhost IP 127.0.0.1. This means that from within pod containers your Keycloak deployment can't be found. Therefore the SSO will fail. The development hack to fix this is situation is to edit the cluster coredns configmap and add a NodeHosts entry for Keycloak. 
+    - Edit the coredns configmap
+
+      ```
+      kubectl edit configmap/coredns -n kube-system
+      ```
+    - add NodeHosts entry for Keycloak using using the passthrough-ingressgateway service EXTERNAL-IP
+      ```
+      data:
+        NodeHosts: |
+          172.18.0.2 k3d-k3s-default-server-0
+          172.18.0.3 k3d-k3s-default-agent-0
+          172.18.0.4 k3d-k3s-default-agent-1
+          172.18.0.5 k3d-k3s-default-agent-2
+          172.18.1.242 keycloak.bigbang.dev
+      ```
+    - Restart the coredns pod so it can pick up the new config
+      ```
+      kubectl rollout restart deployment coredns -n kube-system
+      ```
+    - You might also need to restart the Package app pods before they can detect the new coredns config
+    - Deploy Keycloak using the example dev config values ```docs/developer/example_configs/keycloak-dev-values.yaml```
+
 ### Amazon Linux 2
 
 Here are the configuration steps if you want to use a Fedora based instance. All other steps are similar to Ubuntu.