export.go

  1package github
  2
  3import (
  4	"bytes"
  5	"context"
  6	"encoding/json"
  7	"fmt"
  8	"io/ioutil"
  9	"net/http"
 10	"os"
 11	"strings"
 12	"time"
 13
 14	"github.com/pkg/errors"
 15	"github.com/shurcooL/githubv4"
 16	"golang.org/x/sync/errgroup"
 17
 18	"github.com/MichaelMure/git-bug/bridge/core"
 19	"github.com/MichaelMure/git-bug/bridge/core/auth"
 20	"github.com/MichaelMure/git-bug/bug"
 21	"github.com/MichaelMure/git-bug/cache"
 22	"github.com/MichaelMure/git-bug/entity"
 23	"github.com/MichaelMure/git-bug/identity"
 24	"github.com/MichaelMure/git-bug/repository"
 25)
 26
 27var (
 28	ErrMissingIdentityToken = errors.New("missing identity token")
 29)
 30
 31// githubExporter implement the Exporter interface
 32type githubExporter struct {
 33	conf core.Configuration
 34
 35	// cache identities clients
 36	identityClient map[entity.Id]*githubv4.Client
 37
 38	// github repository ID
 39	repositoryID string
 40
 41	// cache identifiers used to speed up exporting operations
 42	// cleared for each bug
 43	cachedOperationIDs map[entity.Id]string
 44
 45	// cache labels used to speed up exporting labels events
 46	cachedLabels map[string]string
 47}
 48
 49// Init .
 50func (ge *githubExporter) Init(repo *cache.RepoCache, conf core.Configuration) error {
 51	ge.conf = conf
 52	ge.identityClient = make(map[entity.Id]*githubv4.Client)
 53	ge.cachedOperationIDs = make(map[entity.Id]string)
 54	ge.cachedLabels = make(map[string]string)
 55
 56	// preload all clients
 57	err := ge.cacheAllClient(repo)
 58	if err != nil {
 59		return err
 60	}
 61
 62	return nil
 63}
 64
 65func (ge *githubExporter) cacheAllClient(repo *cache.RepoCache) error {
 66	creds, err := auth.List(repo, auth.WithTarget(target), auth.WithKind(auth.KindToken))
 67	if err != nil {
 68		return err
 69	}
 70
 71	for _, cred := range creds {
 72		login, ok := cred.Metadata()[auth.MetaKeyLogin]
 73		if !ok {
 74			_, _ = fmt.Fprintf(os.Stderr, "credential %s is not tagged with Github login\n", cred.ID().Human())
 75			continue
 76		}
 77
 78		user, err := repo.ResolveIdentityImmutableMetadata(metaKeyGithubLogin, login)
 79		if err == identity.ErrIdentityNotExist {
 80			continue
 81		}
 82
 83		if _, ok := ge.identityClient[cred.UserId()]; !ok {
 84			client := buildClient(creds[0].(*auth.Token))
 85			ge.identityClient[cred.UserId()] = client
 86		}
 87	}
 88
 89	return nil
 90}
 91
 92// getClientForIdentity return a githubv4 API client configured with the access token of the given identity.
 93func (ge *githubExporter) getClientForIdentity(userId entity.Id) (*githubv4.Client, error) {
 94	client, ok := ge.identityClient[userId]
 95	if ok {
 96		return client, nil
 97	}
 98
 99	return nil, ErrMissingIdentityToken
100}
101
102// ExportAll export all event made by the current user to Github
103func (ge *githubExporter) ExportAll(ctx context.Context, repo *cache.RepoCache, since time.Time) (<-chan core.ExportResult, error) {
104	out := make(chan core.ExportResult)
105
106	var err error
107	// get repository node id
108	ge.repositoryID, err = getRepositoryNodeID(
109		ctx,
110		ge.defaultToken,
111		ge.conf[keyOwner],
112		ge.conf[keyProject],
113	)
114	if err != nil {
115		return nil, err
116	}
117
118	// query all labels
119	err = ge.cacheGithubLabels(ctx, ge.defaultClient)
120	if err != nil {
121		return nil, err
122	}
123
124	go func() {
125		defer close(out)
126
127		allIdentitiesIds := make([]entity.Id, 0, len(ge.identityClient))
128		for id := range ge.identityClient {
129			allIdentitiesIds = append(allIdentitiesIds, id)
130		}
131
132		allBugsIds := repo.AllBugsIds()
133
134		for _, id := range allBugsIds {
135			b, err := repo.ResolveBug(id)
136			if err != nil {
137				out <- core.NewExportError(errors.Wrap(err, "can't load bug"), id)
138				return
139			}
140
141			select {
142
143			case <-ctx.Done():
144				// stop iterating if context cancel function is called
145				return
146
147			default:
148				snapshot := b.Snapshot()
149
150				// ignore issues created before since date
151				// TODO: compare the Lamport time instead of using the unix time
152				if snapshot.CreatedAt.Before(since) {
153					out <- core.NewExportNothing(b.Id(), "bug created before the since date")
154					continue
155				}
156
157				if snapshot.HasAnyActor(allIdentitiesIds...) {
158					// try to export the bug and it associated events
159					ge.exportBug(ctx, b, since, out)
160				}
161			}
162		}
163	}()
164
165	return out, nil
166}
167
168// exportBug publish bugs and related events
169func (ge *githubExporter) exportBug(ctx context.Context, b *cache.BugCache, since time.Time, out chan<- core.ExportResult) {
170	snapshot := b.Snapshot()
171	var bugUpdated bool
172
173	var bugGithubID string
174	var bugGithubURL string
175
176	// Special case:
177	// if a user try to export a bug that is not already exported to Github (or imported
178	// from Github) and we do not have the token of the bug author, there is nothing we can do.
179
180	// first operation is always createOp
181	createOp := snapshot.Operations[0].(*bug.CreateOperation)
182	author := snapshot.Author
183
184	// skip bug if origin is not allowed
185	origin, ok := snapshot.GetCreateMetadata(core.MetaKeyOrigin)
186	if ok && origin != target {
187		out <- core.NewExportNothing(b.Id(), fmt.Sprintf("issue tagged with origin: %s", origin))
188		return
189	}
190
191	// get github bug ID
192	githubID, ok := snapshot.GetCreateMetadata(metaKeyGithubId)
193	if ok {
194		githubURL, ok := snapshot.GetCreateMetadata(metaKeyGithubUrl)
195		if !ok {
196			// if we find github ID, github URL must be found too
197			err := fmt.Errorf("incomplete Github metadata: expected to find issue URL")
198			out <- core.NewExportError(err, b.Id())
199		}
200
201		// extract owner and project
202		owner, project, err := splitURL(githubURL)
203		if err != nil {
204			err := fmt.Errorf("bad project url: %v", err)
205			out <- core.NewExportError(err, b.Id())
206			return
207		}
208
209		// ignore issue coming from other repositories
210		if owner != ge.conf[keyOwner] && project != ge.conf[keyProject] {
211			out <- core.NewExportNothing(b.Id(), fmt.Sprintf("skipping issue from url:%s", githubURL))
212			return
213		}
214
215		// will be used to mark operation related to a bug as exported
216		bugGithubID = githubID
217		bugGithubURL = githubURL
218
219	} else {
220		// check that we have a token for operation author
221		client, err := ge.getClientForIdentity(author.Id())
222		if err != nil {
223			// if bug is still not exported and we do not have the author stop the execution
224			out <- core.NewExportNothing(b.Id(), fmt.Sprintf("missing author token"))
225			return
226		}
227
228		// create bug
229		id, url, err := createGithubIssue(ctx, client, ge.repositoryID, createOp.Title, createOp.Message)
230		if err != nil {
231			err := errors.Wrap(err, "exporting github issue")
232			out <- core.NewExportError(err, b.Id())
233			return
234		}
235
236		out <- core.NewExportBug(b.Id())
237
238		// mark bug creation operation as exported
239		if err := markOperationAsExported(b, createOp.Id(), id, url); err != nil {
240			err := errors.Wrap(err, "marking operation as exported")
241			out <- core.NewExportError(err, b.Id())
242			return
243		}
244
245		// commit operation to avoid creating multiple issues with multiple pushes
246		if err := b.CommitAsNeeded(); err != nil {
247			err := errors.Wrap(err, "bug commit")
248			out <- core.NewExportError(err, b.Id())
249			return
250		}
251
252		// cache bug github ID and URL
253		bugGithubID = id
254		bugGithubURL = url
255	}
256
257	// cache operation github id
258	ge.cachedOperationIDs[createOp.Id()] = bugGithubID
259
260	for _, op := range snapshot.Operations[1:] {
261		// ignore SetMetadata operations
262		if _, ok := op.(*bug.SetMetadataOperation); ok {
263			continue
264		}
265
266		// ignore operations already existing in github (due to import or export)
267		// cache the ID of already exported or imported issues and events from Github
268		if id, ok := op.GetMetadata(metaKeyGithubId); ok {
269			ge.cachedOperationIDs[op.Id()] = id
270			continue
271		}
272
273		opAuthor := op.GetAuthor()
274		client, err := ge.getClientForIdentity(opAuthor.Id())
275		if err != nil {
276			continue
277		}
278
279		var id, url string
280		switch op := op.(type) {
281		case *bug.AddCommentOperation:
282			// send operation to github
283			id, url, err = addCommentGithubIssue(ctx, client, bugGithubID, op.Message)
284			if err != nil {
285				err := errors.Wrap(err, "adding comment")
286				out <- core.NewExportError(err, b.Id())
287				return
288			}
289
290			out <- core.NewExportComment(op.Id())
291
292			// cache comment id
293			ge.cachedOperationIDs[op.Id()] = id
294
295		case *bug.EditCommentOperation:
296			// Since github doesn't consider the issue body as a comment
297			if op.Target == createOp.Id() {
298
299				// case bug creation operation: we need to edit the Github issue
300				if err := updateGithubIssueBody(ctx, client, bugGithubID, op.Message); err != nil {
301					err := errors.Wrap(err, "editing issue")
302					out <- core.NewExportError(err, b.Id())
303					return
304				}
305
306				out <- core.NewExportCommentEdition(op.Id())
307
308				id = bugGithubID
309				url = bugGithubURL
310
311			} else {
312
313				// case comment edition operation: we need to edit the Github comment
314				commentID, ok := ge.cachedOperationIDs[op.Target]
315				if !ok {
316					panic("unexpected error: comment id not found")
317				}
318
319				eid, eurl, err := editCommentGithubIssue(ctx, client, commentID, op.Message)
320				if err != nil {
321					err := errors.Wrap(err, "editing comment")
322					out <- core.NewExportError(err, b.Id())
323					return
324				}
325
326				out <- core.NewExportCommentEdition(op.Id())
327
328				// use comment id/url instead of issue id/url
329				id = eid
330				url = eurl
331			}
332
333		case *bug.SetStatusOperation:
334			if err := updateGithubIssueStatus(ctx, client, bugGithubID, op.Status); err != nil {
335				err := errors.Wrap(err, "editing status")
336				out <- core.NewExportError(err, b.Id())
337				return
338			}
339
340			out <- core.NewExportStatusChange(op.Id())
341
342			id = bugGithubID
343			url = bugGithubURL
344
345		case *bug.SetTitleOperation:
346			if err := updateGithubIssueTitle(ctx, client, bugGithubID, op.Title); err != nil {
347				err := errors.Wrap(err, "editing title")
348				out <- core.NewExportError(err, b.Id())
349				return
350			}
351
352			out <- core.NewExportTitleEdition(op.Id())
353
354			id = bugGithubID
355			url = bugGithubURL
356
357		case *bug.LabelChangeOperation:
358			if err := ge.updateGithubIssueLabels(ctx, client, bugGithubID, op.Added, op.Removed); err != nil {
359				err := errors.Wrap(err, "updating labels")
360				out <- core.NewExportError(err, b.Id())
361				return
362			}
363
364			out <- core.NewExportLabelChange(op.Id())
365
366			id = bugGithubID
367			url = bugGithubURL
368
369		default:
370			panic("unhandled operation type case")
371		}
372
373		// mark operation as exported
374		if err := markOperationAsExported(b, op.Id(), id, url); err != nil {
375			err := errors.Wrap(err, "marking operation as exported")
376			out <- core.NewExportError(err, b.Id())
377			return
378		}
379
380		// commit at each operation export to avoid exporting same events multiple times
381		if err := b.CommitAsNeeded(); err != nil {
382			err := errors.Wrap(err, "bug commit")
383			out <- core.NewExportError(err, b.Id())
384			return
385		}
386
387		bugUpdated = true
388	}
389
390	if !bugUpdated {
391		out <- core.NewExportNothing(b.Id(), "nothing has been exported")
392	}
393}
394
395// getRepositoryNodeID request github api v3 to get repository node id
396func getRepositoryNodeID(ctx context.Context, token *auth.Token, owner, project string) (string, error) {
397	url := fmt.Sprintf("%s/repos/%s/%s", githubV3Url, owner, project)
398	client := &http.Client{}
399
400	req, err := http.NewRequest("GET", url, nil)
401	if err != nil {
402		return "", err
403	}
404
405	// need the token for private repositories
406	req.Header.Set("Authorization", fmt.Sprintf("token %s", token.Value))
407
408	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
409	defer cancel()
410	req = req.WithContext(ctx)
411
412	resp, err := client.Do(req)
413	if err != nil {
414		return "", err
415	}
416
417	if resp.StatusCode != http.StatusOK {
418		return "", fmt.Errorf("HTTP error %v retrieving repository node id", resp.StatusCode)
419	}
420
421	aux := struct {
422		NodeID string `json:"node_id"`
423	}{}
424
425	data, _ := ioutil.ReadAll(resp.Body)
426	err = resp.Body.Close()
427	if err != nil {
428		return "", err
429	}
430
431	err = json.Unmarshal(data, &aux)
432	if err != nil {
433		return "", err
434	}
435
436	return aux.NodeID, nil
437}
438
439func markOperationAsExported(b *cache.BugCache, target entity.Id, githubID, githubURL string) error {
440	_, err := b.SetMetadata(
441		target,
442		map[string]string{
443			metaKeyGithubId:  githubID,
444			metaKeyGithubUrl: githubURL,
445		},
446	)
447
448	return err
449}
450
451func (ge *githubExporter) cacheGithubLabels(ctx context.Context, gc *githubv4.Client) error {
452	variables := map[string]interface{}{
453		"owner": githubv4.String(ge.conf[keyOwner]),
454		"name":  githubv4.String(ge.conf[keyProject]),
455		"first": githubv4.Int(10),
456		"after": (*githubv4.String)(nil),
457	}
458
459	q := labelsQuery{}
460
461	hasNextPage := true
462	for hasNextPage {
463		// create a new timeout context at each iteration
464		ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
465		defer cancel()
466
467		if err := gc.Query(ctx, &q, variables); err != nil {
468			return err
469		}
470
471		for _, label := range q.Repository.Labels.Nodes {
472			ge.cachedLabels[label.Name] = label.ID
473		}
474
475		hasNextPage = q.Repository.Labels.PageInfo.HasNextPage
476		variables["after"] = q.Repository.Labels.PageInfo.EndCursor
477	}
478
479	return nil
480}
481
482func (ge *githubExporter) getLabelID(gc *githubv4.Client, label string) (string, error) {
483	label = strings.ToLower(label)
484	for cachedLabel, ID := range ge.cachedLabels {
485		if label == strings.ToLower(cachedLabel) {
486			return ID, nil
487		}
488	}
489
490	return "", fmt.Errorf("didn't find label id in cache")
491}
492
493// create a new label and return it github id
494// NOTE: since createLabel mutation is still in preview mode we use github api v3 to create labels
495// see https://developer.github.com/v4/mutation/createlabel/ and https://developer.github.com/v4/previews/#labels-preview
496func (ge *githubExporter) createGithubLabel(ctx context.Context, label, color string) (string, error) {
497	url := fmt.Sprintf("%s/repos/%s/%s/labels", githubV3Url, ge.conf[keyOwner], ge.conf[keyProject])
498	client := &http.Client{}
499
500	params := struct {
501		Name        string `json:"name"`
502		Color       string `json:"color"`
503		Description string `json:"description"`
504	}{
505		Name:  label,
506		Color: color,
507	}
508
509	data, err := json.Marshal(params)
510	if err != nil {
511		return "", err
512	}
513
514	req, err := http.NewRequest("POST", url, bytes.NewBuffer(data))
515	if err != nil {
516		return "", err
517	}
518
519	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
520	defer cancel()
521	req = req.WithContext(ctx)
522
523	// need the token for private repositories
524	req.Header.Set("Authorization", fmt.Sprintf("token %s", ge.defaultToken.Value))
525
526	resp, err := client.Do(req)
527	if err != nil {
528		return "", err
529	}
530
531	if resp.StatusCode != http.StatusCreated {
532		return "", fmt.Errorf("error creating label: response status %v", resp.StatusCode)
533	}
534
535	aux := struct {
536		ID     int    `json:"id"`
537		NodeID string `json:"node_id"`
538		Color  string `json:"color"`
539	}{}
540
541	data, _ = ioutil.ReadAll(resp.Body)
542	defer resp.Body.Close()
543
544	err = json.Unmarshal(data, &aux)
545	if err != nil {
546		return "", err
547	}
548
549	return aux.NodeID, nil
550}
551
552/**
553// create github label using api v4
554func (ge *githubExporter) createGithubLabelV4(gc *githubv4.Client, label, labelColor string) (string, error) {
555	m := createLabelMutation{}
556	input := createLabelInput{
557		RepositoryID: ge.repositoryID,
558		Name:         githubv4.String(label),
559		Color:        githubv4.String(labelColor),
560	}
561
562	parentCtx := context.Background()
563	ctx, cancel := context.WithTimeout(parentCtx, defaultTimeout)
564	defer cancel()
565
566	if err := gc.Mutate(ctx, &m, input, nil); err != nil {
567		return "", err
568	}
569
570	return m.CreateLabel.Label.ID, nil
571}
572*/
573
574func (ge *githubExporter) getOrCreateGithubLabelID(ctx context.Context, gc *githubv4.Client, repositoryID string, label bug.Label) (string, error) {
575	// try to get label id from cache
576	labelID, err := ge.getLabelID(gc, string(label))
577	if err == nil {
578		return labelID, nil
579	}
580
581	// RGBA to hex color
582	rgba := label.Color().RGBA()
583	hexColor := fmt.Sprintf("%.2x%.2x%.2x", rgba.R, rgba.G, rgba.B)
584
585	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
586	defer cancel()
587
588	labelID, err = ge.createGithubLabel(ctx, string(label), hexColor)
589	if err != nil {
590		return "", err
591	}
592
593	return labelID, nil
594}
595
596func (ge *githubExporter) getLabelsIDs(ctx context.Context, gc *githubv4.Client, repositoryID string, labels []bug.Label) ([]githubv4.ID, error) {
597	ids := make([]githubv4.ID, 0, len(labels))
598	var err error
599
600	// check labels ids
601	for _, label := range labels {
602		id, ok := ge.cachedLabels[string(label)]
603		if !ok {
604			// try to query label id
605			id, err = ge.getOrCreateGithubLabelID(ctx, gc, repositoryID, label)
606			if err != nil {
607				return nil, errors.Wrap(err, "get or create github label")
608			}
609
610			// cache label id
611			ge.cachedLabels[string(label)] = id
612		}
613
614		ids = append(ids, githubv4.ID(id))
615	}
616
617	return ids, nil
618}
619
620// create a github issue and return it ID
621func createGithubIssue(ctx context.Context, gc *githubv4.Client, repositoryID, title, body string) (string, string, error) {
622	m := &createIssueMutation{}
623	input := githubv4.CreateIssueInput{
624		RepositoryID: repositoryID,
625		Title:        githubv4.String(title),
626		Body:         (*githubv4.String)(&body),
627	}
628
629	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
630	defer cancel()
631
632	if err := gc.Mutate(ctx, m, input, nil); err != nil {
633		return "", "", err
634	}
635
636	issue := m.CreateIssue.Issue
637	return issue.ID, issue.URL, nil
638}
639
640// add a comment to an issue and return it ID
641func addCommentGithubIssue(ctx context.Context, gc *githubv4.Client, subjectID string, body string) (string, string, error) {
642	m := &addCommentToIssueMutation{}
643	input := githubv4.AddCommentInput{
644		SubjectID: subjectID,
645		Body:      githubv4.String(body),
646	}
647
648	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
649	defer cancel()
650
651	if err := gc.Mutate(ctx, m, input, nil); err != nil {
652		return "", "", err
653	}
654
655	node := m.AddComment.CommentEdge.Node
656	return node.ID, node.URL, nil
657}
658
659func editCommentGithubIssue(ctx context.Context, gc *githubv4.Client, commentID, body string) (string, string, error) {
660	m := &updateIssueCommentMutation{}
661	input := githubv4.UpdateIssueCommentInput{
662		ID:   commentID,
663		Body: githubv4.String(body),
664	}
665
666	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
667	defer cancel()
668
669	if err := gc.Mutate(ctx, m, input, nil); err != nil {
670		return "", "", err
671	}
672
673	return commentID, m.UpdateIssueComment.IssueComment.URL, nil
674}
675
676func updateGithubIssueStatus(ctx context.Context, gc *githubv4.Client, id string, status bug.Status) error {
677	m := &updateIssueMutation{}
678
679	// set state
680	var state githubv4.IssueState
681
682	switch status {
683	case bug.OpenStatus:
684		state = githubv4.IssueStateOpen
685	case bug.ClosedStatus:
686		state = githubv4.IssueStateClosed
687	default:
688		panic("unknown bug state")
689	}
690
691	input := githubv4.UpdateIssueInput{
692		ID:    id,
693		State: &state,
694	}
695
696	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
697	defer cancel()
698
699	if err := gc.Mutate(ctx, m, input, nil); err != nil {
700		return err
701	}
702
703	return nil
704}
705
706func updateGithubIssueBody(ctx context.Context, gc *githubv4.Client, id string, body string) error {
707	m := &updateIssueMutation{}
708	input := githubv4.UpdateIssueInput{
709		ID:   id,
710		Body: (*githubv4.String)(&body),
711	}
712
713	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
714	defer cancel()
715
716	if err := gc.Mutate(ctx, m, input, nil); err != nil {
717		return err
718	}
719
720	return nil
721}
722
723func updateGithubIssueTitle(ctx context.Context, gc *githubv4.Client, id, title string) error {
724	m := &updateIssueMutation{}
725	input := githubv4.UpdateIssueInput{
726		ID:    id,
727		Title: (*githubv4.String)(&title),
728	}
729
730	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
731	defer cancel()
732
733	if err := gc.Mutate(ctx, m, input, nil); err != nil {
734		return err
735	}
736
737	return nil
738}
739
740// update github issue labels
741func (ge *githubExporter) updateGithubIssueLabels(ctx context.Context, gc *githubv4.Client, labelableID string, added, removed []bug.Label) error {
742	reqCtx, cancel := context.WithTimeout(ctx, defaultTimeout)
743	defer cancel()
744
745	wg, ctx := errgroup.WithContext(ctx)
746	if len(added) > 0 {
747		wg.Go(func() error {
748			addedIDs, err := ge.getLabelsIDs(ctx, gc, labelableID, added)
749			if err != nil {
750				return err
751			}
752
753			m := &addLabelsToLabelableMutation{}
754			inputAdd := githubv4.AddLabelsToLabelableInput{
755				LabelableID: labelableID,
756				LabelIDs:    addedIDs,
757			}
758
759			// add labels
760			if err := gc.Mutate(reqCtx, m, inputAdd, nil); err != nil {
761				return err
762			}
763			return nil
764		})
765	}
766
767	if len(removed) > 0 {
768		wg.Go(func() error {
769			removedIDs, err := ge.getLabelsIDs(ctx, gc, labelableID, removed)
770			if err != nil {
771				return err
772			}
773
774			m2 := &removeLabelsFromLabelableMutation{}
775			inputRemove := githubv4.RemoveLabelsFromLabelableInput{
776				LabelableID: labelableID,
777				LabelIDs:    removedIDs,
778			}
779
780			// remove label labels
781			if err := gc.Mutate(reqCtx, m2, inputRemove, nil); err != nil {
782				return err
783			}
784			return nil
785		})
786	}
787
788	return wg.Wait()
789}