Rename gotk binary to flux

Signed-off-by: Hidde Beydals <hello@hidde.co>

cmd/flux/check.go

@@ -0,0 +1,185 @@
+/*
+Copyright 2020 The Flux 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.
+*/
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/blang/semver/v4"
+	"github.com/fluxcd/toolkit/internal/utils"
+	"github.com/spf13/cobra"
+	apimachineryversion "k8s.io/apimachinery/pkg/version"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/clientcmd"
+)
+
+var checkCmd = &cobra.Command{
+	Use:   "check",
+	Short: "Check requirements and installation",
+	Long: `The check command will perform a series of checks to validate that
+the local environment is configured correctly and if the installed components are healthy.`,
+	Example: `  # Run pre-installation checks
+  flux check --pre
+
+  # Run installation checks
+  flux check
+`,
+	RunE: runCheckCmd,
+}
+
+var (
+	checkPre        bool
+	checkComponents []string
+)
+
+type kubectlVersion struct {
+	ClientVersion *apimachineryversion.Info `json:"clientVersion"`
+}
+
+func init() {
+	checkCmd.Flags().BoolVarP(&checkPre, "pre", "", false,
+		"only run pre-installation checks")
+	checkCmd.Flags().StringSliceVar(&checkComponents, "components", defaults.Components,
+		"list of components, accepts comma-separated values")
+	rootCmd.AddCommand(checkCmd)
+}
+
+func runCheckCmd(cmd *cobra.Command, args []string) error {
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	logger.Actionf("checking prerequisites")
+	checkFailed := false
+
+	if !kubectlCheck(ctx, ">=1.18.0") {
+		checkFailed = true
+	}
+
+	if !kubernetesCheck(">=1.16.0") {
+		checkFailed = true
+	}
+
+	if checkPre {
+		if checkFailed {
+			os.Exit(1)
+		}
+		logger.Successf("prerequisites checks passed")
+		return nil
+	}
+
+	logger.Actionf("checking controllers")
+	if !componentsCheck() {
+		checkFailed = true
+	}
+	if checkFailed {
+		os.Exit(1)
+	}
+	logger.Successf("all checks passed")
+	return nil
+}
+
+func kubectlCheck(ctx context.Context, version string) bool {
+	_, err := exec.LookPath("kubectl")
+	if err != nil {
+		logger.Failuref("kubectl not found")
+		return false
+	}
+
+	kubectlArgs := []string{"version", "--client", "--output", "json"}
+	output, err := utils.ExecKubectlCommand(ctx, utils.ModeCapture, kubectlArgs...)
+	if err != nil {
+		logger.Failuref("kubectl version can't be determined")
+		return false
+	}
+
+	kv := &kubectlVersion{}
+	if err = json.Unmarshal([]byte(output), kv); err != nil {
+		logger.Failuref("kubectl version output can't be unmarshaled")
+		return false
+	}
+
+	v, err := semver.ParseTolerant(kv.ClientVersion.GitVersion)
+	if err != nil {
+		logger.Failuref("kubectl version can't be parsed")
+		return false
+	}
+
+	rng, _ := semver.ParseRange(version)
+	if !rng(v) {
+		logger.Failuref("kubectl version must be %s", version)
+		return false
+	}
+
+	logger.Successf("kubectl %s %s", v.String(), version)
+	return true
+}
+
+func kubernetesCheck(version string) bool {
+	cfg, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
+	if err != nil {
+		logger.Failuref("Kubernetes client initialization failed: %s", err.Error())
+		return false
+	}
+
+	client, err := kubernetes.NewForConfig(cfg)
+	if err != nil {
+		logger.Failuref("Kubernetes client initialization failed: %s", err.Error())
+		return false
+	}
+
+	ver, err := client.Discovery().ServerVersion()
+	if err != nil {
+		logger.Failuref("Kubernetes API call failed: %s", err.Error())
+		return false
+	}
+
+	v, err := semver.ParseTolerant(ver.String())
+	if err != nil {
+		logger.Failuref("Kubernetes version can't be determined")
+		return false
+	}
+
+	rng, _ := semver.ParseRange(version)
+	if !rng(v) {
+		logger.Failuref("Kubernetes version must be %s", version)
+		return false
+	}
+
+	logger.Successf("Kubernetes %s %s", v.String(), version)
+	return true
+}
+
+func componentsCheck() bool {
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	ok := true
+	for _, deployment := range checkComponents {
+		kubectlArgs := []string{"-n", namespace, "rollout", "status", "deployment", deployment, "--timeout", timeout.String()}
+		if output, err := utils.ExecKubectlCommand(ctx, utils.ModeCapture, kubectlArgs...); err != nil {
+			logger.Failuref("%s: %s", deployment, strings.TrimSuffix(output, "\n"))
+			ok = false
+		} else {
+			logger.Successf("%s is healthy", deployment)
+		}
+	}
+	return ok
+}