tvl-depot/submitqueue/submitqueue.go
2019-11-27 19:32:14 +01:00

278 lines
8.1 KiB
Go

package submitqueue
import (
"fmt"
"time"
"github.com/tweag/gerrit-queue/gerrit"
"github.com/sirupsen/logrus"
)
// SubmitQueue contains a list of series, a gerrit connection, and some project configuration
type SubmitQueue struct {
Series []*Serie
gerrit gerrit.IClient
ProjectName string
BranchName string
HEAD string
SubmitQueueTag string // the tag used to submit something to the submit queue
URL string
}
// MakeSubmitQueue builds a new submit queue
func MakeSubmitQueue(gerritClient gerrit.IClient, projectName string, branchName string, submitQueueTag string) *SubmitQueue {
return &SubmitQueue{
Series: make([]*Serie, 0),
gerrit: gerritClient,
ProjectName: projectName,
BranchName: branchName,
SubmitQueueTag: submitQueueTag,
}
}
// LoadSeries fills .Series by searching changesets, and assembling them to Series.
func (s *SubmitQueue) LoadSeries(log *logrus.Logger) error {
var queryString = fmt.Sprintf("status:open project:%s branch:%s", s.ProjectName, s.BranchName)
log.Debugf("Running query %s", queryString)
// Download changesets from gerrit
changesets, err := s.gerrit.SearchChangesets(queryString)
if err != nil {
return err
}
// Assemble to series
series, err := AssembleSeries(changesets, log)
if err != nil {
return err
}
// Sort by size
s.Series = SortSeries(series)
return nil
}
// TODO: clear submit queue tag if missing +1/+2?
// IsAutoSubmittable returns true if a given Serie has all the necessary flags set
// meaning it would be fine to rebase and/or submit it.
// This means, every changeset needs to:
// - have the s.SubmitQueueTag hashtag
// - be verified (+1 by CI)
// - be code reviewed (+2 by a human)
func (s *SubmitQueue) IsAutoSubmittable(serie *Serie) bool {
return serie.FilterAllChangesets(func(c *gerrit.Changeset) bool {
return c.HasTag(s.SubmitQueueTag) && c.IsVerified && c.IsCodeReviewed
})
}
// GetChangesetURL returns the URL to view a given changeset
func (s *SubmitQueue) GetChangesetURL(changeset *gerrit.Changeset) string {
return fmt.Sprintf("%s/c/%s/+/%d", s.gerrit.GetBaseURL(), s.ProjectName, changeset.Number)
}
// DoSubmit submits changes that can be submitted,
// and updates `Series` to contain the remaining ones
// Also updates `HEAD`.
func (s *SubmitQueue) DoSubmit(log *logrus.Logger) error {
var remainingSeries []*Serie
// TODO: actually log more!
for _, serie := range s.Series {
serieParentCommitIDs, err := serie.GetParentCommitIDs()
if err != nil {
return err
}
// we can only submit series with a single parent commit (otherwise they're not rebased)
if len(serieParentCommitIDs) != 1 {
return fmt.Errorf("%s has more than one parent commit, skipping", serie.String())
}
// if serie is auto-submittable and rebased on top of current master…
if s.IsAutoSubmittable(serie) && serieParentCommitIDs[0] == s.HEAD {
// submit the last changeset of the series, which submits intermediate ones too
_, err := s.gerrit.SubmitChangeset(serie.ChangeSets[len(serie.ChangeSets)-1])
if err != nil {
// this might fail, for various reasons:
// - developers could have updated the changeset meanwhile, clearing +1/+2 bits
// - master might have advanced, so this changeset isn't rebased on top of master
// TODO: we currently bail out entirely, but should be fine on the
// next loop. We might later want to improve the logic to be a bit more
// smarter (like log and try with the next one)
return err
}
// advance head to the leaf of the current serie for the next iteration
newHead, err := serie.GetLeafCommitID()
if err != nil {
return err
}
s.HEAD = newHead
} else {
remainingSeries = append(remainingSeries, serie)
}
}
s.Series = remainingSeries
return nil
}
// DoRebase rebases the next auto-submittable series on top of current HEAD
// they are still ordered by series size
// After a DoRebase, consumers are supposed to fetch state again via LoadSeries,
// as things most likely have changed, and error handling during partially failed rebases
// is really tricky
func (s *SubmitQueue) DoRebase(log *logrus.Logger) error {
if s.HEAD == "" {
return fmt.Errorf("current HEAD is an empty string, bailing out")
}
for _, serie := range s.Series {
logger := log.WithFields(logrus.Fields{
"serie": serie,
})
if !s.IsAutoSubmittable(serie) {
logger.Debug("skipping non-auto-submittable series")
continue
}
logger.Infof("rebasing on top of %s", s.HEAD)
_, err := s.RebaseSerie(serie, s.HEAD)
if err != nil {
// We skip trivial rebase errors instead of bailing out.
// TODO: we might want to remove s.SubmitQueueTag from the changeset,
// but even without doing it,
// we're merly spanning, and won't get stuck in trying to rebase the same
// changeset over and over again, as some other changeset will likely succeed
// with rebasing and will be merged by DoSubmit.
logger.Warnf("failure while rebasing, continuing with next one: %s", err)
continue
} else {
logger.Info("success rebasing on top of %s", s.HEAD)
break
}
}
return nil
}
// Problem: no inspection during the run
// Problem: record the state
// Result all data necessary to inspect a previous run
// This includes the Series from that run, and all Log Entries collected.
// It also implements the interface required for logrus.Hook.
type Result struct {
LogEntries []*logrus.Entry
Series []Serie
Error error
startTime time.Time
}
// MakeResult produces a new Result struct,
// and initializes startTime with the current time.
func MakeResult() *Result {
return &Result{
startTime: time.Now(),
}
}
// StartTime returns the startTime
func (r Result) StartTime() time.Time {
return r.startTime
}
// EndTime returns the time of the latest log entry
func (r Result) EndTime() time.Time {
if len(r.LogEntries) == 0 {
return r.startTime
}
return r.LogEntries[len(r.LogEntries)-1].Time
}
// Fire is called by logrus on each log event,
// we collect all log entries in the struct variable
func (r *Result) Fire(entry *logrus.Entry) error {
r.LogEntries = append(r.LogEntries, entry)
return nil
}
// Levels is called by logrus to determine whether to Fire the handler.
// As we want to collect all log entries, we return logrus.AllLevels
func (r *Result) Levels() []logrus.Level {
return logrus.AllLevels
}
// Run starts the submit and rebase logic.
func (s *SubmitQueue) Run(fetchOnly bool) *Result {
r := MakeResult()
//TODO: log decisions made and add to some ring buffer
var err error
log := logrus.New()
log.AddHook(r)
commitID, err := s.gerrit.GetHEAD(s.ProjectName, s.BranchName)
if err != nil {
log.Errorf("Unable to retrieve HEAD of branch %s at project %s: %s", s.BranchName, s.ProjectName, err)
r.Error = err
return r
}
s.HEAD = commitID
err = s.LoadSeries(log)
if err != nil {
r.Error = err
return r
}
// copy series to result object
for _, serie := range s.Series {
r.Series = append(r.Series, *serie)
}
if len(s.Series) == 0 {
// Nothing to do!
log.Warn("Nothing to do here")
return r
}
if fetchOnly {
return r
}
err = s.DoSubmit(log)
if err != nil {
r.Error = err
return r
}
err = s.DoRebase(log)
if err != nil {
r.Error = err
return r
}
return r
}
// RebaseSerie rebases a whole serie on top of a given ref
// TODO: only rebase a single changeset. we don't really want to join disconnected series, by rebasing them on top of each other.
func (s *SubmitQueue) RebaseSerie(serie *Serie, ref string) (*Serie, error) {
newSeries := &Serie{
ChangeSets: make([]*gerrit.Changeset, len(serie.ChangeSets)),
}
rebaseOnto := ref
for _, changeset := range serie.ChangeSets {
newChangeset, err := s.gerrit.RebaseChangeset(changeset, rebaseOnto)
if err != nil {
// uh-oh…
// TODO: think about error handling
// TODO: remove the submit queue tag if the rebase fails (but only then, not on other errors)
return newSeries, err
}
newSeries.ChangeSets = append(newSeries.ChangeSets, newChangeset)
// the next changeset should be rebased on top of the current commit
rebaseOnto = newChangeset.CommitID
}
return newSeries, nil
}