The recommended way to update your DAGs with this chart is to build a new docker image with the latest DAG code (`docker build -t my-company/airflow:8a0da78 .`), push it to an accessible registry (`docker push my-company/airflow:8a0da78`), then update the Airflow pods with that image:
## Mounting DAGS using Git-Sync side car with Persistence enabled
This option will use a Persistent Volume Claim with an accessMode of `ReadWriteMany`. The scheduler pod will sync DAGs from a git repository onto the PVC every configured number of seconds. The other pods will read the synced DAGs. Not all volume plugins have support for `ReadWriteMany` accessMode. Refer [Persistent Volume Access Modes](https://kubernetes.io/docs/concepts/storage/persistent-volumes/#access-modes) for details
```bash
helm upgrade airflow . \
--set dags.persistence.enabled=true \
--set dags.gitSync.enabled=true
# you can also override the other persistence or gitSync values
# by setting the dags.persistence.* and dags.gitSync.* values
# Please refer to values.yaml for details
```
## Mounting DAGS using Git-Sync side car without Persistence
This option will use an always running Git-Sync side car on every scheduler,webserver and worker pods. The Git-Sync side car containers will sync DAGs from a git repository every configured number of seconds. If you are using the KubernetesExecutor, Git-sync will run as an initContainer on your worker pods.
```bash
helm upgrade airflow . \
--set dags.persistence.enabled=false \
--set dags.gitSync.enabled=true
# you can also override the other gitSync values
# by setting the dags.gitSync.* values
# Refer values.yaml for details
```
## Mounting DAGS from an externally populated PVC
In this approach, Airflow will read the DAGs from a PVC which has `ReadOnlyMany` or `ReadWriteMany` accessMode. You will have to ensure that the PVC is populated/updated with the required DAGs(this won't be handled by the chart). You can pass in the name of the volume claim to the chart
| `allowPodLaunching` | Allow airflow pods to talk to Kubernetes API to launch more pods | `true` |
| `defaultAirflowRepository` | Fallback docker repository to pull airflow image from | `apache/airflow` |
| `defaultAirflowTag` | Fallback docker image tag to deploy | `1.10.10.1-alpha2-python3.6` |
| `images.airflow.repository` | Docker repository to pull image from. Update this to deploy a custom image | `~` |
| `images.airflow.tag` | Docker image tag to pull image from. Update this to deploy a new custom image tag | `~` |
| `images.airflow.pullPolicy` | PullPolicy for airflow image | `IfNotPresent` |
| `images.flower.repository` | Docker repository to pull image from. Update this to deploy a custom image | `~` |
| `images.flower.tag` | Docker image tag to pull image from. Update this to deploy a new custom image tag | `~` |
| `images.flower.pullPolicy` | PullPolicy for flower image | `IfNotPresent` |
| `images.statsd.repository` | Docker repository to pull image from. Update this to deploy a custom image | `astronomerinc/ap-statsd-exporter` |
| `images.statsd.tag` | Docker image tag to pull image from. Update this to deploy a new custom image tag | `~` |
| `images.statsd.pullPolicy` | PullPolicy for statsd-exporter image | `IfNotPresent` |
| `images.redis.repository` | Docker repository to pull image from. Update this to deploy a custom image | `redis` |
| `images.redis.tag` | Docker image tag to pull image from. Update this to deploy a new custom image tag | `6-buster` |
| `images.redis.pullPolicy` | PullPolicy for redis image | `IfNotPresent` |
| `images.pgbouncer.repository` | Docker repository to pull image from. Update this to deploy a custom image | `astronomerinc/ap-pgbouncer` |
| `images.pgbouncer.tag` | Docker image tag to pull image from. Update this to deploy a new custom image tag | `~` |
| `images.pgbouncer.pullPolicy` | PullPolicy for pgbouncer image | `IfNotPresent` |
| `images.pgbouncerExporter.repository` | Docker repository to pull image from. Update this to deploy a custom image | `astronomerinc/ap-pgbouncer-exporter` |
| `images.pgbouncerExporter.tag` | Docker image tag to pull image from. Update this to deploy a new custom image tag | `~` |
| `images.pgbouncerExporter.pullPolicy` | PullPolicy for pgbouncer-exporter image | `IfNotPresent` |
| `env` | Environment variables key/values to mount into Airflow pods | `[]` |
| `secret` | Secret name/key pairs to mount into Airflow pods | `[]` |
| `data.metadataSecretName` | Secret name to mount Airflow connection string from | `~` |
| `data.resultBackendSecretName` | Secret name to mount Celery result backend connection string from | `~` |
| `data.metadataConection` | Field separated connection data (alternative to secret name) | `{}` |
Specify each parameter using the `--set key=value[,key=value]` argument to `helm install`. For example,
```bash
helm install --name my-release \
--set executor=CeleryExecutor \
--set enablePodLaunching=false .
```
## Autoscaling with KEDA
KEDA stands for Kubernetes Event Driven Autoscaling. [KEDA](https://github.com/kedacore/keda) is a custom controller that allows users to create custom bindings
to the Kubernetes [Horizontal Pod Autoscaler](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/).
We've built an experimental scaler that allows users to create scalers based on postgreSQL queries. For the moment this exists
It may take a few minutes. Confirm the pods are up:
```
kubectl get pods --all-namespaces
helm list -n airflow
```
Run `kubectl port-forward svc/airflow-webserver 8080:8080 -n airflow`
to port-forward the Airflow UI to http://localhost:8080/ to cofirm Airflow is working.
**Build a Docker image from your DAGs:**
1. Start a project using [astro-cli](https://github.com/astronomer/astro-cli), which will generate a Dockerfile, and load your DAGs in. You can test locally before pushing to kind with `astro airflow start`.
