Nginx Ingress Integrator

Ingress in the Kubernetes context is defined as “An API object that manages external access to the services in a cluster, typically HTTP. Ingress may provide load balancing, SSL termination and name-based virtual hosting.”

In the context of this operator, there are two key concepts to understand:

• The first is an ingress controller, which is a cluster-level service that provides ingress for applications.
• The second is an ingress resource, which is something defined by an application running within a cluster describing how ingress for it should be configured.

This operator configures an ingress resource which is then picked up by an ingress controller to determine how the ingress for a given application is configured.

What does this charm do?

To enable ingress via Nginx for sidecar charms, we’ve created this nginx-ingress-integrator charm. To use this charm you’ll need to have an Nginx Ingress Controller deployed into your K8s cluster.

The charm can be configured via a relation, or via juju config directly. See the ingress library documentation for more details on an easy method to integrate other charms.

The reason for offering both relation and direct juju config support is that providing the relation means charm authors can make the experience better for end users by implementing the relation. If a charm doesn’t implement the relation it can still be used with this charm and configured manually.

Using the relation, the charm supports the following features:

• Rate limiting (with an allowlist for exclusions by a CIDR).
• Setting maximum allowed body size for file uploads.
• Configuring retrying of errors against the next server.
• A session cookie to use for cookie-based session affinity, and the age of that cookie.
• The TLS certificate to use for your service if applicable.

All of these options can also be configured at the time of deployment. In addition there’s an ingress-class option to use when your cluster has multiple ingress controllers. This allows you to target the correct controller.