c12s-kubespray/docs/ambassador.md

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# Ambassador
The [Ambassador API Gateway](https://github.com/datawire/ambassador) provides all the functionality of a traditional ingress controller
(e.g., path-based routing) while exposing many additional capabilities such as authentication,
URL rewriting, CORS, rate limiting, and automatic metrics collection.
## Installation
### Configuration
* `ingress_ambassador_namespace` (default `ambassador`): namespace for installing Ambassador.
* `ingress_ambassador_update_window` (default `0 0 * * SUN`): _crontab_-like expression
for specifying when the Operator should try to update the Ambassador API Gateway.
* `ingress_ambassador_version` (defaulkt: `*`): SemVer rule for versions allowed for
installation/updates.
* `ingress_ambassador_secure_port` (default: 443): HTTPS port to listen at.
* `ingress_ambassador_insecure_port` (default: 80): HTTP port to listen at.
### Ambassador Operator
This Ambassador addon deploys the Ambassador Operator, which in turn will install
the [Ambassador API Gateway](https://github.com/datawire/ambassador) in
a Kubernetes cluster.
The Ambassador Operator is a Kubernetes Operator that controls Ambassador's complete lifecycle
in your cluster, automating many of the repeatable tasks you would otherwise have to perform
yourself. Once installed, the Operator will complete installations and seamlessly upgrade to new
versions of Ambassador as they become available.
## Usage
The following example creates simple http-echo services and an `Ingress` object
to route to these services.
Note well that the [Ambassador API Gateway](https://github.com/datawire/ambassador) will automatically load balance `Ingress` resources
that include the annotation `kubernetes.io/ingress.class=ambassador`. All the other
resources will be just ignored.
```yaml
kind: Pod
apiVersion: v1
metadata:
name: foo-app
labels:
app: foo
spec:
containers:
- name: foo-app
image: hashicorp/http-echo
args:
- "-text=foo"
---
kind: Service
apiVersion: v1
metadata:
name: foo-service
spec:
selector:
app: foo
ports:
# Default port used by the image
- port: 5678
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: example-ingress
annotations:
kubernetes.io/ingress.class: ambassador
spec:
rules:
- http:
paths:
- path: /foo
backend:
serviceName: foo-service
servicePort: 5678
```
Now you can test that the ingress is working with curl:
```console
$ export AMB_IP=$(kubectl get service ambassador -n ambassador -o 'go-template={{range .status.loadBalancer.ingress}}{{print .ip "\n"}}{{end}}')
$ curl $AMB_IP/foo
foo
```