github.com/SamarSidharth/kpt@v0.0.0-20231122062228-c7d747ae3ace/commands/alpha/rpkg/update/discover.go

// Copyright 2022 The kpt 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 update

import (
	"fmt"
	"io"
	"strings"

	porchapi "github.com/GoogleContainerTools/kpt/porch/api/porch/v1alpha1"
	configapi "github.com/GoogleContainerTools/kpt/porch/api/porchconfig/v1alpha1"
	"github.com/spf13/cobra"
	"golang.org/x/mod/semver"
	"k8s.io/cli-runtime/pkg/printers"
	"sigs.k8s.io/controller-runtime/pkg/client"
)

func (r *runner) discoverUpdates(cmd *cobra.Command, args []string) error {
	var prs []porchapi.PackageRevision
	var errs []string
	if len(args) == 0 || r.discover == downstream {
		prs = r.prs
	} else {
		for i := range args {
			pr := r.findPackageRevision(args[i])
			if pr == nil {
				errs = append(errs, fmt.Sprintf("could not find package revision %s", args[i]))
				continue
			}
			prs = append(prs, *pr)
		}
	}
	if len(errs) > 0 {
		return fmt.Errorf("errors:\n  %s", strings.Join(errs, "\n  "))
	}

	repositories, err := r.getRepositories()
	if err != nil {
		return err
	}

	switch r.discover {
	case upstream:
		return r.findUpstreamUpdates(prs, repositories, cmd.OutOrStdout())
	case downstream:
		return r.findDownstreamUpdates(prs, repositories, args, cmd.OutOrStdout())
	default: // this should never happen, because we validate in preRunE
		return fmt.Errorf("invalid argument %q for --discover", r.discover)
	}
}

func (r *runner) findUpstreamUpdates(prs []porchapi.PackageRevision, repositories *configapi.RepositoryList, w io.Writer) error {
	var upstreamUpdates [][]string
	for _, pr := range prs {
		availableUpdates, upstreamName, _, err := r.availableUpdates(pr.Status.UpstreamLock, repositories)
		if err != nil {
			return fmt.Errorf("could not parse upstreamLock in Kptfile of package %q: %s", pr.Name, err.Error())
		}
		if len(availableUpdates) == 0 {
			upstreamUpdates = append(upstreamUpdates, []string{pr.Name, upstreamName, "No update available"})
		} else {
			var revisions []string
			for i := range availableUpdates {
				revisions = append(revisions, availableUpdates[i].Spec.Revision)
			}
			upstreamUpdates = append(upstreamUpdates, []string{pr.Name, upstreamName, strings.Join(revisions, ", ")})
		}
	}
	return printUpstreamUpdates(upstreamUpdates, w)
}

func (r *runner) findDownstreamUpdates(prs []porchapi.PackageRevision, repositories *configapi.RepositoryList,
	args []string, w io.Writer) error {
	// map from the upstream package revision to a list of its downstream package revisions
	downstreamUpdatesMap := make(map[string][]porchapi.PackageRevision)

	for _, pr := range prs {
		availableUpdates, _, draftName, err := r.availableUpdates(pr.Status.UpstreamLock, repositories)
		if err != nil {
			return fmt.Errorf("could not parse upstreamLock in Kptfile of package %q: %s", pr.Name, err.Error())
		}
		for _, update := range availableUpdates {
			key := fmt.Sprintf("%s:%s:%s", update.Name, update.Spec.Revision, draftName)
			downstreamUpdatesMap[key] = append(downstreamUpdatesMap[key], pr)
		}
	}
	return printDownstreamUpdates(downstreamUpdatesMap, args, w)
}

func (r *runner) availableUpdates(upstreamLock *porchapi.UpstreamLock, repositories *configapi.RepositoryList) ([]porchapi.PackageRevision, string, string, error) {
	var availableUpdates []porchapi.PackageRevision
	var upstream string

	if upstreamLock == nil || upstreamLock.Git == nil {
		return nil, "", "", nil
	}
	var currentUpstreamRevision string
	var draftName string

	// separate the revision number from the package name
	lastIndex := strings.LastIndex(upstreamLock.Git.Ref, "/")
	if lastIndex < 0 {
		// "/" not found - upstreamLock.Git.Ref is not in the expected format
		return nil, "", "", fmt.Errorf("malformed upstreamLock.Git.Ref %q", upstreamLock.Git.Ref)
	}

	if strings.HasPrefix(upstreamLock.Git.Ref, "drafts") {
		// The upstream is not a published package, so doesn't have a revision number.
		// Use v0 as a placeholder, so that all published packages get returned as available
		// updates.
		currentUpstreamRevision = "v0"
		draftName = upstreamLock.Git.Ref[lastIndex+1:]
	} else {
		currentUpstreamRevision = upstreamLock.Git.Ref[lastIndex+1:]
	}

	// upstream.git.ref could look like drafts/pkgname/version or pkgname/version
	upstreamPackageName := upstreamLock.Git.Ref[:lastIndex]
	upstreamPackageName = strings.TrimPrefix(upstreamPackageName, "drafts")
	upstreamPackageName = strings.TrimPrefix(upstreamPackageName, "/")

	if !strings.HasSuffix(upstreamLock.Git.Repo, ".git") {
		upstreamLock.Git.Repo += ".git"
	}

	// find a repo that matches the upstreamLock
	var revisions []porchapi.PackageRevision
	for _, repo := range repositories.Items {
		if repo.Spec.Type != configapi.RepositoryTypeGit {
			// we are not currently supporting non-git repos for updates
			continue
		}
		if !strings.HasSuffix(repo.Spec.Git.Repo, ".git") {
			repo.Spec.Git.Repo += ".git"
		}
		if upstreamLock.Git.Repo == repo.Spec.Git.Repo {
			upstream = repo.Name
			revisions = r.getUpstreamRevisions(repo, upstreamPackageName)
		}
	}

	for _, upstreamRevision := range revisions {
		switch cmp := semver.Compare(upstreamRevision.Spec.Revision, currentUpstreamRevision); {
		case cmp > 0: // upstreamRevision > currentUpstreamRevision
			availableUpdates = append(availableUpdates, upstreamRevision)
		case cmp == 0, cmp < 0: // upstreamRevision <= currentUpstreamRevision, do nothing
		}
	}

	return availableUpdates, upstream, draftName, nil
}

// fetches all registered repositories
func (r *runner) getRepositories() (*configapi.RepositoryList, error) {
	repoList := configapi.RepositoryList{}
	err := r.client.List(r.ctx, &repoList, &client.ListOptions{})
	return &repoList, err
}

// fetches all package revision numbers for packages with the name upstreamPackageName from the repo
func (r *runner) getUpstreamRevisions(repo configapi.Repository, upstreamPackageName string) []porchapi.PackageRevision {
	var result []porchapi.PackageRevision
	for _, pkgRev := range r.prs {
		if !porchapi.LifecycleIsPublished(pkgRev.Spec.Lifecycle) {
			// only consider published packages
			continue
		}
		if pkgRev.Spec.RepositoryName == repo.Name && pkgRev.Spec.PackageName == upstreamPackageName {
			result = append(result, pkgRev)
		}
	}
	return result
}

func printUpstreamUpdates(upstreamUpdates [][]string, w io.Writer) error {
	printer := printers.GetNewTabWriter(w)
	if _, err := fmt.Fprintln(printer, "PACKAGE REVISION\tUPSTREAM REPOSITORY\tUPSTREAM UPDATES"); err != nil {
		return err
	}
	for _, pkgRev := range upstreamUpdates {
		if _, err := fmt.Fprintln(printer, strings.Join(pkgRev, "\t")); err != nil {
			return err
		}
	}
	return printer.Flush()
}

func printDownstreamUpdates(downstreamUpdatesMap map[string][]porchapi.PackageRevision, args []string, w io.Writer) error {
	var downstreamUpdates [][]string
	for upstreamPkgRev, downstreamPkgRevs := range downstreamUpdatesMap {
		split := strings.Split(upstreamPkgRev, ":")
		upstreamPkgRevName := split[0]
		upstreamPkgRevNum := split[1]
		draftName := split[2]
		for _, downstreamPkgRev := range downstreamPkgRevs {
			if draftName != "" {
				// the upstream package revision is not published, so does not have a revision number
				downstreamUpdates = append(downstreamUpdates,
					[]string{upstreamPkgRevName, downstreamPkgRev.Name, fmt.Sprintf("(draft %q)->%s", draftName, upstreamPkgRevNum)})
				continue
			}
			// figure out which upstream revision the downstream revision is based on
			lastIndex := strings.LastIndex(downstreamPkgRev.Status.UpstreamLock.Git.Ref, "v")
			if lastIndex < 0 {
				// this ref isn't formatted the way that porch expects
				continue
			}
			downstreamRev := downstreamPkgRev.Status.UpstreamLock.Git.Ref[lastIndex:]
			downstreamUpdates = append(downstreamUpdates,
				[]string{upstreamPkgRevName, downstreamPkgRev.Name, fmt.Sprintf("%s->%s", downstreamRev, upstreamPkgRevNum)})
		}
	}

	var pkgRevsToPrint [][]string
	if len(args) != 0 {
		for _, arg := range args {
			for _, pkgRev := range downstreamUpdates {
				// filter out irrelevant packages based on provided args
				if arg == pkgRev[0] {
					pkgRevsToPrint = append(pkgRevsToPrint, pkgRev)
				}
			}
		}
	} else {
		pkgRevsToPrint = downstreamUpdates
	}

	printer := printers.GetNewTabWriter(w)
	if len(pkgRevsToPrint) == 0 {
		if _, err := fmt.Fprintln(printer, "All downstream packages are up to date."); err != nil {
			return err
		}
	} else {
		if _, err := fmt.Fprintln(printer, "PACKAGE REVISION\tDOWNSTREAM PACKAGE\tDOWNSTREAM UPDATE"); err != nil {
			return err
		}
		for _, pkgRev := range pkgRevsToPrint {
			if _, err := fmt.Fprintln(printer, strings.Join(pkgRev, "\t")); err != nil {
				return err
			}
		}
	}
	return printer.Flush()
}