Plug in out-of-process adapter into mixer in the context of K8s cluster

Hong_Zhang · March 19, 2019, 1:18pm

Hello,

I am following this out-of-process-adapter walk through to learn how to write an out-of-process mixer adapter.

The way it makes the mixer aware of the new adapter is by passing in the --configStoreURL in the mixs command line:

$GOPATH/out/linux_amd64/release/mixs server --configStoreURL=fs://$(pwd)/mixer/adapter/mygrpcadapter/testdata

The example works well with the standalone mixer server, but how do you do that (inject the adapter resource config into Mixer’s configuration store) in the context of a kubernetes cluster?

In the walk-through guide, it points to a Prometheus adapter for example:

You may look at Prometheus Out of process adapter for a working example.

Looking at the code, I can see the mixer adapter will be deployed to the kubernetes cluster as a service:

github.com

istio/istio/blob/eb2ca5bc6eb7154695464591b63d4629695d5460/mixer/test/prometheus/cmd/prometheusadapter.yaml

# Copyright 2017 Istio Authors
#
#   Licensed 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.

##################################################################################################
# prometheusadapter service
##################################################################################################
apiVersion: v1
kind: Service
metadata:

This file has been truncated. show original

But it’s not clear to me how the mixer is made aware of this adapter. Can someone please help me connect the missing dots as our use case needs to happen in the context of kubernetes cluster.

It will be great if there is another walk through with the Promethues example outlining the steps of how to deploy a mixer adapter and then plug it in the mixer in the context of a kubernetes cluster.

Thank you!

venilnoronha · March 19, 2019, 2:50pm

Here’s a tutorial I wrote -
https://venilnoronha.io/set-sail-a-production-ready-istio-adapter

Venil

theganyo · March 19, 2019, 5:17pm

Hi Hong,

The key is in the handler CRD. There is a config for “connection” that needs to be a valid address for Mixer to connect to. I have an example here.

Scott

Hong_Zhang · March 19, 2019, 5:35pm

Thanks much Venil! I will follow through the tutorial and let you know if I have any follow up questions.

Hong_Zhang · March 19, 2019, 5:38pm

Thanks Scott! So in the cluster scenario, there is no need to inject the adapter resource config into Mixer’s configuration store?

In the standalone case, we need to pass in the --configStoreURL in the mixs command line:

$GOPATH/out/linux_amd64/release/mixs server --configStoreURL=fs://$(pwd)/mixer/adapter/mygrpcadapter/testdata

There is no equivalent step for this in the cluster scenario?

theganyo · March 19, 2019, 5:55pm

Right. That step is because Mixer has no context when it runs standalone.