helm_helpers.go

/*
Copyright (C) 2020 Synopsys, Inc.

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.
*/

package util

import (
	"bytes"
	"encoding/json"
	"fmt"
	"net/http"
	"path/filepath"
	"regexp"
	"strings"

	"github.com/blackducksoftware/synopsysctl/pkg/api"
	"github.com/ghodss/yaml"
	"github.com/imdario/mergo"
	log "github.com/sirupsen/logrus"
	"helm.sh/helm/v3/pkg/action"
	"helm.sh/helm/v3/pkg/chart"
	"helm.sh/helm/v3/pkg/chart/loader"
	"helm.sh/helm/v3/pkg/cli"
	"helm.sh/helm/v3/pkg/kube"
	"helm.sh/helm/v3/pkg/release"
	"helm.sh/helm/v3/pkg/releaseutil"
	"k8s.io/cli-runtime/pkg/genericclioptions"
	"k8s.io/client-go/rest"
	"k8s.io/klog"
)

var settings = cli.New()

// CreateWithHelm3 uses the helm NewInstall action to create a resource in the cluster
// Modified from https://github.com/openshift/console/blob/cdf6b189b71e488033ecaba7d90258d9f9453478/pkg/helm/actions/install_chart.go
// Helm Actions: https://github.com/helm/helm/tree/9bc7934f350233fa72a11d2d29065aa78ab62792/pkg/action
func CreateWithHelm3(releaseName, namespace, chartURL string, vals map[string]interface{}, kubeConfig string, dryRun bool, extraFiles ...string) error {
	// Check if resouce already exists
	existingRelease, _ := GetWithHelm3(releaseName, namespace, kubeConfig)
	if existingRelease != nil {
		return fmt.Errorf("release '%s' already exists in namespace '%s'", existingRelease.Name, existingRelease.Namespace)
	}

	// Create the new Release
	actionConfig, err := CreateHelmActionConfiguration(kubeConfig, "", namespace)
	if err != nil {
		return fmt.Errorf("failed to create the release config due to %s", err)
	}

	chart, err := LoadChart(chartURL, actionConfig)
	if err != nil {
		return fmt.Errorf("failed to load application resources at '%s' due to %s", chartURL, err)
	}
	validInstallableChart, err := isChartInstallable(chart)
	if !validInstallableChart {
		return fmt.Errorf("release at '%s' is not installable: %s", chartURL, err)
	}
	if chart.Metadata.Deprecated {
		log.Warnf("the release at '%s' is deprecated", chartURL)
	}
	// TODO: determine if we will check dependencies...
	// if req := chart.Metadata.Dependencies; req != nil {
	// 	// If CheckDependencies returns an error, we have unfulfilled dependencies.
	// 	// As of Helm 2.4.0, this is treated as a stopping condition:
	// 	// https://github.com/helm/helm/issues/2209
	// 	if err := action.CheckDependencies(chart, req); err != nil {
	// 		if client.DependencyUpdate {
	// 			man := &downloader.Manager{
	// 				Out:              out,
	// 				ChartPath:        cp,
	// 				Keyring:          client.ChartPathOptions.Keyring,
	// 				SkipUpdate:       false,
	// 				Getters:          p,
	// 				RepositoryConfig: settings.RepositoryConfig,
	// 				RepositoryCache:  settings.RepositoryCache,
	// 			}
	// 			if err := man.Update(); err != nil {
	// 				return nil, err
	// 			}
	// 		} else {
	// 			return nil, err
	// 		}
	// 	}
	// }

	client := action.NewInstall(actionConfig)
	if client.Version == "" && client.Devel {
		client.Version = ">0.0.0-0"
	}
	client.ReleaseName = releaseName
	client.Namespace = namespace
	client.DryRun = dryRun

	if err := mergeExtraFilesToConfig(chart, vals, extraFiles); err != nil {
		return fmt.Errorf("failed to merge extra configuration files during create due to %s", err)
	}

	_, err = client.Run(chart, vals) // deploy the chart into the namespace from the actionConfig
	if err != nil {
		return fmt.Errorf("failed to run install due to %s", err)
	}
	return nil
}

// UpdateWithHelm3 uses the helm NewUpgrade action to update a resource in the cluster
func UpdateWithHelm3(releaseName, namespace, chartURL string, vals map[string]interface{}, kubeConfig string, extraFiles ...string) error {
	actionConfig, err := CreateHelmActionConfiguration(kubeConfig, "", namespace)
	if err != nil {
		return err
	}
	if releaseExists := ReleaseExists(releaseName, namespace, kubeConfig); !releaseExists {
		return fmt.Errorf("release '%s' does not exist", releaseName)
	}

	chart, err := LoadChart(chartURL, actionConfig)
	if err != nil {
		return fmt.Errorf("failed to load release at '%s' for updating: %s", chartURL, err)
	}
	validInstallableChart, err := isChartInstallable(chart)
	if !validInstallableChart {
		return fmt.Errorf("release at '%s' is not installable: %s", chartURL, err)
	}

	client := action.NewUpgrade(actionConfig)
	if client.Version == "" && client.Devel {
		client.Version = ">0.0.0-0"
	}
	client.Namespace = namespace

	if err := mergeExtraFilesToConfig(chart, vals, extraFiles); err != nil {
		return fmt.Errorf("failed to merge extra configuration files during update due to %s", err)
	}

	client.ResetValues = true                     // rememeber the values that have been set previously
	_, err = client.Run(releaseName, chart, vals) // updates the release in the namespace from the actionConfig
	if err != nil {
		return fmt.Errorf("failed to run upgrade: %s", err)
	}
	return nil
}

// TemplateWithHelm3 prints the kube manifest files for a resource
func TemplateWithHelm3(releaseName, namespace, chartURL string, vals map[string]interface{}, extraFiles ...string) error {
	actionConfig, err := CreateHelmActionConfiguration("", "", namespace)
	if err != nil {
		return err
	}
	chart, err := LoadChart(chartURL, actionConfig)
	if err != nil {
		return err
	}
	validInstallableChart, err := isChartInstallable(chart)
	if !validInstallableChart {
		return err
	}

	if err := mergeExtraFilesToConfig(chart, vals, extraFiles); err != nil {
		return fmt.Errorf("failed to merge extra configuration files during template due to %s", err)
	}

	templateOutput, err := RenderManifests(releaseName, namespace, chart, vals, actionConfig)
	if err != nil {
		return fmt.Errorf("failed to render kube manifest files due to %s", err)
	}
	fmt.Printf("%+v\n", templateOutput)
	return nil
}

// RenderManifests converts a helm chart to a string of the kube manifest files
// Modified from https://github.com/openshift/console/blob/cdf6b189b71e488033ecaba7d90258d9f9453478/pkg/helm/actions/template_test.go
func RenderManifests(releaseName, namespace string, chart *chart.Chart, vals map[string]interface{}, actionConfig *action.Configuration) (string, error) {
	var showFiles []string
	response := make(map[string]string)
	validate := false
	includeCrds := true
	emptyResponse := ""

	client := action.NewInstall(actionConfig)
	client.DryRun = true
	client.ReleaseName = releaseName
	client.Namespace = namespace
	client.Replace = true // Skip the releaseName check
	client.ClientOnly = !validate

	rel, err := client.Run(chart, vals)
	if err != nil {
		return emptyResponse, err
	}

	var manifests bytes.Buffer
	var output bytes.Buffer

	if includeCrds {
		for _, f := range rel.Chart.CRDs() {
			fmt.Fprintf(&manifests, "---\n# Source: %s\n%s\n", f.Name, f.Data)
		}
	}

	fmt.Fprintln(&manifests, strings.TrimSpace(rel.Manifest))

	if !client.DisableHooks {
		for _, m := range rel.Hooks {
			fmt.Fprintf(&manifests, "---\n# Source: %s\n%s\n", m.Path, m.Manifest)
		}
	}

	// if we have a list of files to render, then check that each of the
	// provided files exists in the chart.
	if len(showFiles) > 0 {
		splitManifests := releaseutil.SplitManifests(manifests.String())
		manifestNameRegex := regexp.MustCompile("# Source: [^/]+/(.+)")
		var manifestsToRender []string
		for _, f := range showFiles {
			missing := true
			for _, manifest := range splitManifests {
				submatch := manifestNameRegex.FindStringSubmatch(manifest)
				if len(submatch) == 0 {
					continue
				}
				manifestName := submatch[1]
				// manifest.Name is rendered using linux-style filepath separators on Windows as
				// well as macOS/linux.
				manifestPathSplit := strings.Split(manifestName, "/")
				manifestPath := filepath.Join(manifestPathSplit...)

				// if the filepath provided matches a manifest path in the
				// chart, render that manifest
				if f == manifestPath {
					manifestsToRender = append(manifestsToRender, manifest)
					missing = false
				}
			}
			if missing {
				return "", fmt.Errorf("could not find template '%s' in release resources", f)
			}
			for _, m := range manifestsToRender {
				response[f] = m
				fmt.Fprintf(&output, "---\n%s\n", m)
			}
		}
	} else {
		fmt.Fprintf(&output, "%s", manifests.String())
	}
	return output.String(), nil
}

// DeleteWithHelm3 uses the helm NewUninstall action to delete a resource from the cluster
func DeleteWithHelm3(releaseName, namespace, kubeConfig string) error {
	actionConfig, err := CreateHelmActionConfiguration(kubeConfig, "", namespace)
	if err != nil {
		return err
	}
	if releaseExists := ReleaseExists(releaseName, namespace, kubeConfig); !releaseExists {
		return fmt.Errorf("release '%s' does not exist", releaseName)
	}
	client := action.NewUninstall(actionConfig)
	_, err = client.Run(releaseName) // deletes the releaseName from the namespace in the actionConfig
	if err != nil {
		return fmt.Errorf("failed to run uninstall due to %s", err)
	}
	return nil
}

// GetWithHelm3 uses the helm NewGet action to return a Release with information about
// a resource from the cluster
func GetWithHelm3(releaseName, namespace, kubeConfig string) (*release.Release, error) {
	actionConfig, err := CreateHelmActionConfiguration(kubeConfig, "", namespace)
	if err != nil {
		return nil, err
	}
	// Check if the Release Exists
	aList := action.NewList(actionConfig) // NewGet provides bad error message if release doesn't exist
	charts, err := aList.Run()
	if err != nil {
		return nil, fmt.Errorf("failed to run get due to %s", err)
	}
	for _, release := range charts {
		if release.Name == releaseName && release.Namespace == namespace {
			return release, nil
		}
	}
	return nil, fmt.Errorf("unable to find release '%s' in namespace '%s'", releaseName, namespace)
}

// CreateHelmActionConfiguration creates an action.Configuration that points to the specified cluster and namespace
func CreateHelmActionConfiguration(kubeConfig, kubeContext, namespace string) (*action.Configuration, error) {
	// TODO: look into using GetActionConfigurations()
	actionConfig := new(action.Configuration)
	if err := actionConfig.Init(kube.GetConfig(kubeConfig, kubeContext, namespace), namespace, "secret", func(format string, v ...interface{}) {}); err != nil {
		return nil, err
	}
	return actionConfig, nil
}

type configFlagsWithTransport struct {
	*genericclioptions.ConfigFlags
	Transport *http.RoundTripper
}

// GetActionConfigurations creates an action.Configuration that points to the specified cluster and namespace
// TODO - this function specifies more values than CreateHelmActionConfiguration(), consider using this
func GetActionConfigurations(host, namespace, token string, transport *http.RoundTripper) *action.Configuration {

	confFlags := &configFlagsWithTransport{
		ConfigFlags: &genericclioptions.ConfigFlags{
			APIServer:   &host,
			BearerToken: &token,
			Namespace:   &namespace,
		},
		Transport: transport,
	}
	inClusterCfg, err := rest.InClusterConfig()

	if err != nil {
		fmt.Print("Running outside cluster, CAFile is unset")
	} else {
		confFlags.CAFile = &inClusterCfg.CAFile
	}
	conf := new(action.Configuration)
	conf.Init(confFlags, namespace, "secrets", klog.Infof)

	return conf
}

// LoadChart returns a chart from the specified chartURL
// Modified from https://github.com/openshift/console/blob/master/pkg/helm/actions/template_test.go
func LoadChart(chartURL string, actionConfig *action.Configuration) (*chart.Chart, error) {
	client := action.NewInstall(actionConfig)

	// Get full path - checks local machine and chart repository
	chartFullPath, err := client.ChartPathOptions.LocateChart(chartURL, settings)
	if err != nil {
		return nil, fmt.Errorf("failed to locate resources at '%s' due to %s", chartURL, err)
	}

	chart, err := loader.Load(chartFullPath)
	if err != nil {
		return nil, fmt.Errorf("failed to load resources from '%s' due to %s", chartFullPath, err)
	}
	return chart, nil
}

// isChartInstallable validates if a chart can be installed
//
// Only the "application" chart type is installable
func isChartInstallable(ch *chart.Chart) (bool, error) {
	switch ch.Metadata.Type {
	case "", "application":
		return true, nil
	}
	return false, fmt.Errorf("resources at '%s' are not installable", ch.Metadata.Type)
}

// ReleaseExists verifies that a resources is deployed in the cluster
func ReleaseExists(releaseName, namespace, kubeConfig string) bool {
	actionConfig, err := CreateHelmActionConfiguration(kubeConfig, "", namespace)
	if err != nil {
		return false
	}
	client := action.NewGet(actionConfig)
	release, err := client.Run(releaseName) // lists the releases in the namespace from the actionConfig
	if err != nil || release == nil {
		return false
	}
	return true
}

func mergeExtraFilesToConfig(ch *chart.Chart, vals map[string]interface{}, extraFiles []string) error {
	for _, fileName := range extraFiles {
		found := false
		for _, chartFile := range ch.Files {
			if fileName == chartFile.Name {
				found = true
				patch := make(map[string]interface{})
				if err := yaml.Unmarshal(chartFile.Data, &patch); err != nil {
					return err
				}
				if err := mergo.Merge(&vals, patch, mergo.WithOverride); err != nil {
					return err
				}
				break
			}
		}
		if !found {
			return fmt.Errorf("couldn't find file '%s' in release resources", fileName)
		}
	}
	return nil
}

// SetHelmValueInMap adds the finalValue into the valueMapPointer at the location specified
// by the keyList
// valueMapPointer - a map for helm values (maps are pointers in Golang)
//  - it is used to track the current map being updated
// keyList - an ordered list of keys that lead to the location in the valueMapPointer to place the finalValue
// finalValue - the value to set in the map
func SetHelmValueInMap(valueMapPointer map[string]interface{}, keyList []string, finalValue interface{}) {
	for i, currKey := range keyList {
		if i == (len(keyList) - 1) { // at the last key -> set the value
			valueMapPointer[currKey] = finalValue
			return
		}
		if nextMap, _ := valueMapPointer[currKey]; nextMap != nil { // key is in map -> go to next map
			valueMapPointer = nextMap.(map[string]interface{})
		} else { // key is not in the map -> add the key and next key; go to next map
			nextKey := keyList[i+1]
			valueMapPointer[currKey] = map[string]interface{}{nextKey: nil}
			nextMap := valueMapPointer[currKey].(map[string]interface{})
			valueMapPointer = nextMap
		}
	}
}

// GetHelmValueFromMap returns an interface{} if the value exists in the map
func GetHelmValueFromMap(valueMapPointer map[string]interface{}, keyList []string) interface{} {
	for i, currKey := range keyList {
		currVal, ok := valueMapPointer[currKey]
		if !ok { // value doesn't exist - invalid path
			return nil
		}
		if i == (len(keyList) - 1) { // at the last key -> return the value
			return currVal
		}
		valueMapPointer, ok = currVal.(map[string]interface{})
		if !ok { // got a finalValue instead of a map - invalid path
			return nil
		}
	}
	return nil
}

// GetValueFromRelease merges the default Chart Values with the user's set values
// to find the value that is current set in the Release
func GetValueFromRelease(release *release.Release, keyList []string) interface{} {
	chartValues := release.Chart.Values
	userConfig := release.Config
	releaseValues := MergeMaps(chartValues, userConfig)
	return GetHelmValueFromMap(releaseValues, keyList)
}

// GetReleaseValues merges the default Chart Values with the user's set values
// and retuns that set of values
func GetReleaseValues(release *release.Release) map[string]interface{} {
	chartValues := release.Chart.Values
	userConfig := release.Config
	return MergeMaps(chartValues, userConfig)
}

// MergeMaps Copied from https://github.com/helm/helm/blob/9b42702a4bced339ff424a78ad68dd6be6e1a80a/pkg/cli/values/options.go#L88
func MergeMaps(a, b map[string]interface{}) map[string]interface{} {
	out := make(map[string]interface{}, len(a))
	for k, v := range a {
		out[k] = v
	}
	for k, v := range b {
		if v, ok := v.(map[string]interface{}); ok {
			if bv, ok := out[k]; ok {
				if bv, ok := bv.(map[string]interface{}); ok {
					out[k] = MergeMaps(bv, v)
					continue
				}
			}
		}
		out[k] = v
	}
	return out
}

// GetDeploymentResources reads the deployment resource file path and sets the Helm resource maps
func GetDeploymentResources(deploymentResourceFilePath string, valueMapPointer map[string]interface{}, heapMaxMemoryName string) {
	data, err := ReadFileData(deploymentResourceFilePath)
	if err != nil {
		log.Fatalf("failed to read deployment resources file: %s", err)
	}
	deploymentResources := make(map[string]api.DeploymentResource, 0)
	err = json.Unmarshal([]byte(data), &deploymentResources)
	if err != nil {
		log.Fatalf("failed to unmarshal deployment resources structs: %s", err)
	}

	for key, value := range deploymentResources {
		if value.Replicas != nil {
			SetHelmValueInMap(valueMapPointer, []string{key, "replicas"}, *value.Replicas)
		}
		if value.HeapMaxMemory != nil {
			setStringPtrInHelmValueInMap(valueMapPointer, []string{key, heapMaxMemoryName}, value.HeapMaxMemory)
		}
		setStringPtrInHelmValueInMap(valueMapPointer, []string{key, "resources", "limits", "cpu"}, value.Resources.Limits.CPU)
		setStringPtrInHelmValueInMap(valueMapPointer, []string{key, "resources", "limits", "memory"}, value.Resources.Limits.Memory)
		setStringPtrInHelmValueInMap(valueMapPointer, []string{key, "resources", "requests", "cpu"}, value.Resources.Requests.CPU)
		setStringPtrInHelmValueInMap(valueMapPointer, []string{key, "resources", "requests", "memory"}, value.Resources.Requests.Memory)
	}
}

func setStringPtrInHelmValueInMap(valueMapPointer map[string]interface{}, keyList []string, value *string) {
	if value != nil {
		SetHelmValueInMap(valueMapPointer, keyList, *value)
	}
}