autodetect.go

/*
 * 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.
 */

// Copied from grafana-operator
// With the Apache License: https://github.com/grafana/grafana-operator/blob/master/LICENSE
// See: https://github.com/grafana/grafana-operator/blob/master/controllers/autodetect/main.go
// Package autodetect is for auto-detecting traits from the environment (platform, APIs, ...).
package controllers

import (
	"k8s.io/client-go/discovery"
	"k8s.io/client-go/rest"
)

var _ AutoDetect = (*autoDetect)(nil)

// AutoDetect provides an assortment of routines that auto-detect traits based on the runtime.
type AutoDetect interface {
	IsOpenshift() (bool, error)
}

type autoDetect struct {
	dcl discovery.DiscoveryInterface
}

// New creates a new auto-detection worker, using the given client when talking to the current cluster.
func NewAutodetect(restConfig *rest.Config) (AutoDetect, error) {
	dcl, err := discovery.NewDiscoveryClientForConfig(restConfig)
	if err != nil {
		// it's pretty much impossible to get into this problem, as most of the
		// code branches from the previous call just won't fail at all,
		// but let's handle this error anyway...
		return nil, err
	}

	return &autoDetect{
		dcl: dcl,
	}, nil
}

// Platform returns the detected platform this operator is running on. Possible values: Kubernetes, OpenShift.
func (a *autoDetect) IsOpenshift() (bool, error) {
	apiList, err := a.dcl.ServerGroups()
	if err != nil {
		return false, err
	}

	apiGroups := apiList.Groups
	for i := range apiGroups {
		if apiGroups[i].Name == "route.openshift.io" {
			return true, nil
		}
	}

	return false, nil
}