Miretpl commented on code in PR #67012: URL: https://github.com/apache/airflow/pull/67012#discussion_r3486840710
########## chart/kustomize-overlays/kerberos/README.rst: ########## @@ -0,0 +1,162 @@ +.. Licensed to the Apache Software Foundation (ASF) under one + or more contributor license agreements. See the NOTICE file + distributed with this work for additional information + regarding copyright ownership. The ASF licenses this file + to you under the Apache License, Version 2.0 (the + "License"); you may not use this file except in compliance + with the License. You may obtain a copy of the License at + +.. http://www.apache.org/licenses/LICENSE-2.0 + +.. Unless required by applicable law or agreed to in writing, + software distributed under the License is distributed on an + "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + KIND, either express or implied. See the License for the + specific language governing permissions and limitations + under the License. + +Kerberos Test KDC Overlay +========================= + +This overlay stands up a throwaway in-cluster MIT Kerberos KDC, creates +the ``airflow/airflow.<namespace>.svc.cluster.local`` service principal, +and stores its keytab in a Secret named ``<release>-kerberos-keytab``. +It is a standalone addition; no resource produced by the Helm chart is +modified. + +It is intended as a proof-of-concept of how a non-Airflow component +(in this case Kerberos infrastructure) can be expressed as a Kustomize +overlay alongside the chart, rather than baked into the chart itself. +The keytab Secret it produces is consumable as-is by the chart's +existing kerberos sidecar (``kerberos.enabled=true``, +``kerberos.keytab=/etc/airflow.keytab``, +``extraSecrets.<release>-kerberos-keytab: {}``). + +.. warning:: + + The KDC pod uses a fixed admin password and stores its database in + an ``emptyDir``. Do not connect production workloads to it. Treat it + as a test fixture only. + +Prerequisites +------------- + +* The Airflow chart installed in the same namespace (any executor). +* ``kubectl`` access sufficient to apply Deployments, Services, + ConfigMaps, Secrets, ServiceAccounts/Roles/RoleBindings, and Jobs in + that namespace. + +Usage +----- + +Reference this overlay from your own kustomization and substitute the +release name and namespace. A minimal example: + +.. code-block:: yaml + + # my-overlay/kustomization.yaml + apiVersion: kustomize.config.k8s.io/v1beta1 + kind: Kustomization + namespace: airflow + + resources: + - github.com/apache/airflow/chart/kustomize-overlays/kerberos?ref=helm-chart/1.22.0 + +Apply with: + +.. code-block:: bash + + kubectl apply -k my-overlay/ + +For a quick test, you can also just substitute the placeholders inline: + +.. code-block:: bash + + kubectl kustomize chart/kustomize-overlays/kerberos | \ + sed -e 's/RELEASE-NAME/airflow/g' -e 's/NAMESPACE/airflow/g' | \ + kubectl apply -n airflow -f - + +This is exactly what ``breeze k8s smoke-test-overlay kerberos`` does +during the local and CI smoke test. + +Wiring the keytab into the chart's sidecar +------------------------------------------ + +The chart's kerberos sidecar (``workers.celery.kerberosInitContainer``, +``workers.celery.kerberosSidecar``, ``workers.kubernetes.kerberosInitContainer``, +``workers.kubernetes.kerberosSidecar``) always mounts a keytab Secret whose +name is fixed by the chart to ``<release>-kerberos-keytab`` (rendered by the +``kerberos_keytab_secret`` helper from the release fullname). There is no +chart value that points the sidecar at a differently named Secret. + +This overlay produces a Secret with exactly that name, so nothing in +``values.yaml`` needs to reference it. Enable kerberos and leave +``keytabBase64Content`` unset, so the chart does not render its own +(competing) keytab Secret and instead mounts the one this overlay creates: + +.. code-block:: yaml + + # values.yaml fragment + kerberos: + enabled: true + ccacheMountPath: /var/kerberos-ccache + keytabPath: /etc/airflow.keytab + principal: airflow/[email protected] + # keytabBase64Content left unset on purpose: the overlay supplies the + # <release>-kerberos-keytab Secret that the sidecar mounts. Review Comment: ```suggestion ``` It is already mentioned in the description above this example. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
