buildbucket/cli/print.go - infra/luci/luci-go - Git at Google

 // Copyright 2019 The LUCI 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 cli

 import (
 	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
 	"os"
 	"strings"
 	"time"
 	"unicode/utf8"

 	"github.com/golang/protobuf/jsonpb"
 	"github.com/golang/protobuf/proto"
 	"github.com/mgutz/ansi"
 	"google.golang.org/grpc/status"
 	"google.golang.org/protobuf/types/known/timestamppb"

 	"go.chromium.org/luci/common/data/stringset"
 	"go.chromium.org/luci/common/data/text/color"
 	"go.chromium.org/luci/common/data/text/indented"

 	bb "go.chromium.org/luci/buildbucket"
 	pb "go.chromium.org/luci/buildbucket/proto"
 	"go.chromium.org/luci/buildbucket/protoutil"
 )

 var (
 	ansiWhiteBold      = ansi.ColorCode("white+b")
 	ansiWhiteUnderline = ansi.ColorCode("white+u")
 	ansiStatus         = map[pb.Status]string{
 		pb.Status_SCHEDULED:     ansi.LightWhite,
 		pb.Status_STARTED:       ansi.LightYellow,
 		pb.Status_SUCCESS:       ansi.LightGreen,
 		pb.Status_FAILURE:       ansi.LightRed,
 		pb.Status_INFRA_FAILURE: ansi.LightMagenta,
 	}
 )

 // printer can print a buildbucket build to a io.Writer in a human-friendly
 // format.
 //
 // First time writing fails, the error is saved to Err.
 // Further attempts to write are noop.
 type printer struct {
 	// Err is not nil if printing to the writer failed.
 	// If it is not nil, methods are noop.
 	Err error

 	nowFn func() time.Time

 	// used to indent text. printer.f always writes to this writer.
 	indent indented.Writer
 }

 func newPrinter(w io.Writer, disableColor bool, nowFn func() time.Time) *printer {
 	// Stack writers together.
 	// w always points to the stack top.

 	p := &printer{nowFn: nowFn}

 	if disableColor {
 		w = &color.StripWriter{Writer: w}
 	}

 	p.indent.Writer = w
 	p.indent.UseSpaces = true
 	return p
 }

 func newStdioPrinters(disableColor bool) (stdout, stderr *printer) {
 	disableColor = disableColor || shouldDisableColors()
 	stdout = newPrinter(os.Stdout, disableColor, time.Now)
 	stderr = newPrinter(os.Stderr, disableColor, time.Now)
 	return
 }

 // f prints a formatted message.
 func (p *printer) f(format string, args ...interface{}) {
 	if p.Err != nil {
 		return
 	}
 	if _, err := fmt.Fprintf(&p.indent, format, args...); err != nil && err != io.ErrShortWrite {
 		p.Err = err
 	}
 }

 // fw is like f, but appends whitespace such that the printed string takes at
 // least minWidth.
 // Appends at least one space.
 func (p *printer) fw(minWidth int, format string, args ...interface{}) {
 	s := fmt.Sprintf(format, args...)
 	pad := minWidth - utf8.RuneCountInString(s)
 	if pad < 1 {
 		pad = 1
 	}
 	p.f("%s%s", s, strings.Repeat(" ", pad))
 }

 // JSONPB prints pb in either compact or indented JSON format according to the
 // provided compact boolean
 func (p *printer) JSONPB(pb proto.Message, compact bool) {
 	m := &jsonpb.Marshaler{}
 	buf := &bytes.Buffer{}
 	if err := m.Marshal(buf, pb); err != nil {
 		panic(fmt.Errorf("failed to marshal a message: %s", err))
 	}

 	out := &bytes.Buffer{}
 	var err error
 	if compact {
 		err = json.Compact(out, buf.Bytes())
 	} else {
 		// Note: json.Marshal indents JSON more nicely than jsonpb.Marshaler.Indent.
 		err = json.Indent(out, buf.Bytes(), "", "  ")
 	}
 	if err != nil {
 		panic(err)
 	}

 	p.f("%s\n", out.Bytes())
 }

 // Build prints b. Panic when id, status or any fields under builder is missing
 func (p *printer) Build(b *pb.Build) {
 	// Id, Status and Builder are explicitly added to field mask so they should
 	// always be present. Doing defensive check here to avoid any unexpected
 	// conditions to corrupt the printed build.
 	if b.Id == 0 {
 		panic(fmt.Errorf("expect non zero id present in the build"))
 	}
 	if b.Status == pb.Status_STATUS_UNSPECIFIED {
 		panic(fmt.Errorf("expect non zero value status present in the build"))
 	}
 	if builder := b.Builder; builder == nil ||
 		builder.Project == "" || builder.Bucket == "" || builder.Builder == "" {
 		panic(fmt.Errorf("expect builder present in the build and all fields under builder should be non zero value. Got: %v", builder))
 	}

 	// Print the build URL bold, underline and a color matching the status.
 	p.f("%s%s%shttp://ci.chromium.org/b/%d", ansiWhiteBold, ansiWhiteUnderline, ansiStatus[b.Status], b.Id)
 	// Undo underline.
 	p.f("%s%s%s ", ansi.Reset, ansiWhiteBold, ansiStatus[b.Status])
 	p.fw(10, "%s", b.Status)
 	p.f("'%s/%s/%s", b.Builder.Project, b.Builder.Bucket, b.Builder.Builder)
 	if b.Number != 0 {
 		p.f("/%d", b.Number)
 	}
 	p.f("'%s\n", ansi.Reset)

 	// Summary.
 	if b.SummaryMarkdown != "" {
 		p.attr("Summary")
 		p.summary(b.SummaryMarkdown)
 	}

 	experiments := stringset.NewFromSlice(b.Input.GetExperiments()...)

 	var systemTags []string
 	if experiments.Has(bb.ExperimentNonProduction) {
 		systemTags = append(systemTags, "Experimental")
 	}
 	if experiments.Has(bb.ExperimentBBCanarySoftware) {
 		systemTags = append(systemTags, "Canary")
 	}
 	if len(systemTags) > 0 {
 		for i, t := range systemTags {
 			if i > 0 {
 				p.f(" ")
 			}
 			p.keyword(t)
 		}
 		p.f("\n")
 	}

 	// Timing.
 	if b.CreateTime != nil {
 		p.buildTime(b)
 		p.f("\n")
 	}

 	if b.CreatedBy != "" {
 		p.attr("By")
 		p.f("%s\n", b.CreatedBy)
 	}

 	// Commit, CLs and tags.
 	if c := b.Input.GetGitilesCommit(); c != nil {
 		p.attr("Commit")
 		p.commit(c)
 		p.f("\n")
 	}
 	for _, cl := range b.Input.GetGerritChanges() {
 		p.attr("CL")
 		p.change(cl)
 		p.f("\n")
 	}
 	for _, t := range b.Tags {
 		p.attr("Tag")
 		p.f("%s:%s\n", t.Key, t.Value)
 	}

 	// Properties
 	if props := b.Input.GetProperties(); props != nil {
 		p.attr("Input properties")
 		p.JSONPB(props, false)
 	}

 	if props := b.Output.GetProperties(); props != nil {
 		p.attr("Output properties")
 		p.JSONPB(props, false)
 	}

 	// Experiments
 	if exps := b.Input.GetExperiments(); len(exps) > 0 {
 		p.attr("Experiments")
 		p.f("\n")
 		p.indent.Level += 2
 		for _, exp := range exps {
 			p.f("%s\n", exp)
 		}
 		p.indent.Level -= 2
 	}

 	// Steps
 	p.steps(b.Steps)
 }

 // commit prints c.
 func (p *printer) commit(c *pb.GitilesCommit) {
 	if c.Id == "" {
 		p.linkf("https://%s/%s/+/%s", c.Host, c.Project, c.Ref)
 		return
 	}

 	switch c.Host {
 	// This shamelessly hardcodes https://cr-rev.appspot.com/_ah/api/crrev/v1/projects response
 	// TODO(nodir): make an RPC and cache on the file system.
 	case
 		"aomedia.googlesource.com",
 		"boringssl.googlesource.com",
 		"chromium.googlesource.com",
 		"gerrit.googlesource.com",
 		"webrtc.googlesource.com":
 		p.linkf("https://crrev.com/" + c.Id)
 	default:
 		p.linkf("https://%s/%s/+/%s", c.Host, c.Project, c.Id)
 	}
 	if c.Ref != "" {
 		p.f(" on %s", c.Ref)
 	}
 }

 // change prints cl.
 func (p *printer) change(cl *pb.GerritChange) {
 	switch {
 	case cl.Host == "chromium-review.googlesource.com":
 		p.linkf("https://crrev.com/c/%d/%d", cl.Change, cl.Patchset)
 	case cl.Host == "chrome-internal-review.googlesource.com":
 		p.linkf("https://crrev.com/i/%d/%d", cl.Change, cl.Patchset)
 	default:
 		p.linkf("https://%s/c/%s/+/%d/%d", cl.Host, cl.Project, cl.Change, cl.Patchset)
 	}
 }

 // steps print steps.
 func (p *printer) steps(steps []*pb.Step) {
 	maxNameWidth := 0
 	for _, s := range steps {
 		if w := utf8.RuneCountInString(s.Name); w > maxNameWidth {
 			maxNameWidth = w
 		}
 	}

 	for _, s := range steps {
 		p.f("%sStep ", ansiStatus[s.Status])
 		p.fw(maxNameWidth+5, "%q", s.Name)
 		p.fw(10, "%s", s.Status)

 		// Print duration.
 		durString := ""
 		if start := s.StartTime.AsTime(); s.StartTime != nil {
 			var stepDur time.Duration
 			if end := s.EndTime.AsTime(); s.EndTime != nil {
 				stepDur = end.Sub(start)
 			} else {
 				now := p.nowFn()
 				stepDur = now.Sub(start.In(now.Location()))
 			}
 			durString = truncateDuration(stepDur).String()
 		}
 		p.fw(10, "%s", durString)

 		// Print log names.
 		// Do not print log URLs because they are very long and
 		// bb has `log` subcommand.
 		if len(s.Logs) > 0 {
 			p.f("Logs: ")
 			for i, l := range s.Logs {
 				if i > 0 {
 					p.f(", ")
 				}
 				p.f("%q", l.Name)
 			}
 		}

 		p.f("%s\n", ansi.Reset)

 		p.indent.Level += 2
 		if s.SummaryMarkdown != "" {
 			// TODO(nodir): transform lists of links to look like logs
 			p.summary(s.SummaryMarkdown)
 		}
 		p.indent.Level -= 2
 	}
 }

 func (p *printer) buildTime(b *pb.Build) {
 	now := p.nowFn()
 	created := readTimestamp(b.CreateTime).In(now.Location())
 	started := readTimestamp(b.StartTime).In(now.Location())
 	ended := readTimestamp(b.EndTime).In(now.Location())

 	if created.IsZero() {
 		return
 	}
 	p.keyword("Created")
 	p.f(" ")
 	p.dateTime(created)

 	// Since the `fields` part of the request is partially controlled by the user,
 	// the nil timestamp fields in fetched build aren't trustworthy.
 	// So, check by `status` first,which is always set, and only then try to print
 	// additional information if semantically fitting.

 	if b.Status == pb.Status_SCHEDULED {
 		if !p.isJustNow(created) {
 			p.f(", ")
 			p.keyword("waiting")
 			p.f(" for %s, ", truncateDuration(now.Sub(created)))
 		}
 		return
 	}

 	if !started.IsZero() {
 		p.f(", ")
 		p.keyword("waited")
 		p.f(" %s, ", truncateDuration(started.Sub(created)))
 		p.keyword("started")
 		p.f(" ")
 		p.time(started)
 	}

 	if !protoutil.IsEnded(b.Status) {
 		if !started.IsZero() {
 			// running now
 			p.f(", ")
 			p.keyword("running")
 			p.f(" for %s", truncateDuration(now.Sub(started)))
 		}
 	} else {
 		// ended
 		if !started.IsZero() {
 			// started in the past
 			p.f(", ")
 			p.keyword("ran")
 			p.f(" for %s", truncateDuration(ended.Sub(started)))
 		}
 		if !ended.IsZero() {
 			p.f(", ")
 			p.keyword("ended")
 			p.f(" ")
 			p.time(ended)
 		}
 	}
 }

 func (p *printer) summary(summaryMarkdown string) {
 	// TODO(nodir): color markdown.
 	p.f("%s\n", strings.TrimSpace(summaryMarkdown))
 }

 func (p *printer) dateTime(t time.Time) {
 	if p.isJustNow(t) {
 		p.f("just now")
 	} else {
 		p.date(t)
 		p.f(" ")
 		p.time(t)
 	}
 }

 func (p *printer) date(t time.Time) {
 	if p.isToday(t) {
 		p.f("today")
 	} else {
 		p.f("on %s", t.Format("2006-01-02"))
 	}
 }

 func (p *printer) time(t time.Time) {
 	if p.isJustNow(t) {
 		p.f("just now")
 	} else {
 		p.f("at %s", t.Format("15:04:05"))
 	}
 }

 func (p *printer) isJustNow(t time.Time) bool {
 	now := p.nowFn()
 	elapsed := now.Sub(t.In(now.Location()))
 	return elapsed > 0 && elapsed < 10*time.Second
 }

 func (p *printer) attr(s string) {
 	p.keyword(s)
 	p.f(": ")
 }

 func (p *printer) keyword(s string) {
 	p.f("%s%s%s", ansiWhiteBold, s, ansi.Reset)
 }

 func (p *printer) linkf(format string, args ...interface{}) {
 	p.f("%s", ansiWhiteUnderline)
 	p.f(format, args...)
 	p.f("%s", ansi.Reset)
 }

 // Error prints the err. If err is a gRPC error, then prints only the message
 // without the code.
 func (p *printer) Error(err error) {
 	st, _ := status.FromError(err)
 	p.f("%s", st.Message())
 }

 // readTimestamp converts ts to time.Time.
 // Returns zero if ts is invalid.
 func readTimestamp(ts *timestamppb.Timestamp) time.Time {
 	if err := ts.CheckValid(); err != nil {
 		return time.Time{}
 	}
 	t := ts.AsTime()
 	return t
 }

 func (p *printer) isToday(t time.Time) bool {
 	now := p.nowFn()
 	nYear, nMonth, nDay := now.Date()
 	tYear, tMonth, tDay := t.In(now.Location()).Date()
 	return tYear == nYear && tMonth == nMonth && tDay == nDay
 }

 var durTransactions = []struct{ threshold, round time.Duration }{
 	{time.Hour, time.Minute},
 	{time.Minute, time.Second},
 	{time.Second, time.Second / 10},
 	{time.Millisecond, time.Millisecond},
 }

 // truncateDuration truncates d to make it more human-readable.
 func truncateDuration(d time.Duration) time.Duration {
 	for _, t := range durTransactions {
 		if d > t.threshold {
 			return d.Round(t.round)
 		}
 	}
 	return d
 }
	// Copyright 2019 The LUCI 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 cli

	import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"os"
	"strings"
	"time"
	"unicode/utf8"

	"github.com/golang/protobuf/jsonpb"
	"github.com/golang/protobuf/proto"
	"github.com/mgutz/ansi"
	"google.golang.org/grpc/status"
	"google.golang.org/protobuf/types/known/timestamppb"

	"go.chromium.org/luci/common/data/stringset"
	"go.chromium.org/luci/common/data/text/color"
	"go.chromium.org/luci/common/data/text/indented"

	bb "go.chromium.org/luci/buildbucket"
	pb "go.chromium.org/luci/buildbucket/proto"
	"go.chromium.org/luci/buildbucket/protoutil"
	)

	var (
	ansiWhiteBold = ansi.ColorCode("white+b")
	ansiWhiteUnderline = ansi.ColorCode("white+u")
	ansiStatus = map[pb.Status]string{
	pb.Status_SCHEDULED: ansi.LightWhite,
	pb.Status_STARTED: ansi.LightYellow,
	pb.Status_SUCCESS: ansi.LightGreen,
	pb.Status_FAILURE: ansi.LightRed,
	pb.Status_INFRA_FAILURE: ansi.LightMagenta,
	}
	)

	// printer can print a buildbucket build to a io.Writer in a human-friendly
	// format.
	//
	// First time writing fails, the error is saved to Err.
	// Further attempts to write are noop.
	type printer struct {
	// Err is not nil if printing to the writer failed.
	// If it is not nil, methods are noop.
	Err error

	nowFn func() time.Time

	// used to indent text. printer.f always writes to this writer.
	indent indented.Writer
	}

	func newPrinter(w io.Writer, disableColor bool, nowFn func() time.Time) *printer {
	// Stack writers together.
	// w always points to the stack top.

	p := &printer{nowFn: nowFn}

	if disableColor {
	w = &color.StripWriter{Writer: w}
	}

	p.indent.Writer = w
	p.indent.UseSpaces = true
	return p
	}

	func newStdioPrinters(disableColor bool) (stdout, stderr *printer) {
	disableColor = disableColor \|\| shouldDisableColors()
	stdout = newPrinter(os.Stdout, disableColor, time.Now)
	stderr = newPrinter(os.Stderr, disableColor, time.Now)
	return
	}

	// f prints a formatted message.
	func (p *printer) f(format string, args ...interface{}) {
	if p.Err != nil {
	return
	}
	if _, err := fmt.Fprintf(&p.indent, format, args...); err != nil && err != io.ErrShortWrite {
	p.Err = err
	}
	}

	// fw is like f, but appends whitespace such that the printed string takes at
	// least minWidth.
	// Appends at least one space.
	func (p *printer) fw(minWidth int, format string, args ...interface{}) {
	s := fmt.Sprintf(format, args...)
	pad := minWidth - utf8.RuneCountInString(s)
	if pad < 1 {
	pad = 1
	}
	p.f("%s%s", s, strings.Repeat(" ", pad))
	}

	// JSONPB prints pb in either compact or indented JSON format according to the
	// provided compact boolean
	func (p *printer) JSONPB(pb proto.Message, compact bool) {
	m := &jsonpb.Marshaler{}
	buf := &bytes.Buffer{}
	if err := m.Marshal(buf, pb); err != nil {
	panic(fmt.Errorf("failed to marshal a message: %s", err))
	}

	out := &bytes.Buffer{}
	var err error
	if compact {
	err = json.Compact(out, buf.Bytes())
	} else {
	// Note: json.Marshal indents JSON more nicely than jsonpb.Marshaler.Indent.
	err = json.Indent(out, buf.Bytes(), "", " ")
	}
	if err != nil {
	panic(err)
	}

	p.f("%s\n", out.Bytes())
	}

	// Build prints b. Panic when id, status or any fields under builder is missing
	func (p printer) Build(b pb.Build) {
	// Id, Status and Builder are explicitly added to field mask so they should
	// always be present. Doing defensive check here to avoid any unexpected
	// conditions to corrupt the printed build.
	if b.Id == 0 {
	panic(fmt.Errorf("expect non zero id present in the build"))
	}
	if b.Status == pb.Status_STATUS_UNSPECIFIED {
	panic(fmt.Errorf("expect non zero value status present in the build"))
	}
	if builder := b.Builder; builder == nil \|\|
	builder.Project == "" \|\| builder.Bucket == "" \|\| builder.Builder == "" {
	panic(fmt.Errorf("expect builder present in the build and all fields under builder should be non zero value. Got: %v", builder))
	}

	// Print the build URL bold, underline and a color matching the status.
	p.f("%s%s%shttp://ci.chromium.org/b/%d", ansiWhiteBold, ansiWhiteUnderline, ansiStatus[b.Status], b.Id)
	// Undo underline.
	p.f("%s%s%s ", ansi.Reset, ansiWhiteBold, ansiStatus[b.Status])
	p.fw(10, "%s", b.Status)
	p.f("'%s/%s/%s", b.Builder.Project, b.Builder.Bucket, b.Builder.Builder)
	if b.Number != 0 {
	p.f("/%d", b.Number)
	}
	p.f("'%s\n", ansi.Reset)

	// Summary.
	if b.SummaryMarkdown != "" {
	p.attr("Summary")
	p.summary(b.SummaryMarkdown)
	}

	experiments := stringset.NewFromSlice(b.Input.GetExperiments()...)

	var systemTags []string
	if experiments.Has(bb.ExperimentNonProduction) {
	systemTags = append(systemTags, "Experimental")
	}
	if experiments.Has(bb.ExperimentBBCanarySoftware) {
	systemTags = append(systemTags, "Canary")
	}
	if len(systemTags) > 0 {
	for i, t := range systemTags {
	if i > 0 {
	p.f(" ")
	}
	p.keyword(t)
	}
	p.f("\n")
	}

	// Timing.
	if b.CreateTime != nil {
	p.buildTime(b)
	p.f("\n")
	}

	if b.CreatedBy != "" {
	p.attr("By")
	p.f("%s\n", b.CreatedBy)
	}

	// Commit, CLs and tags.
	if c := b.Input.GetGitilesCommit(); c != nil {
	p.attr("Commit")
	p.commit(c)
	p.f("\n")
	}
	for _, cl := range b.Input.GetGerritChanges() {
	p.attr("CL")
	p.change(cl)
	p.f("\n")
	}
	for _, t := range b.Tags {
	p.attr("Tag")
	p.f("%s:%s\n", t.Key, t.Value)
	}

	// Properties
	if props := b.Input.GetProperties(); props != nil {
	p.attr("Input properties")
	p.JSONPB(props, false)
	}

	if props := b.Output.GetProperties(); props != nil {
	p.attr("Output properties")
	p.JSONPB(props, false)
	}

	// Experiments
	if exps := b.Input.GetExperiments(); len(exps) > 0 {
	p.attr("Experiments")
	p.f("\n")
	p.indent.Level += 2
	for _, exp := range exps {
	p.f("%s\n", exp)
	}
	p.indent.Level -= 2
	}

	// Steps
	p.steps(b.Steps)
	}

	// commit prints c.
	func (p printer) commit(c pb.GitilesCommit) {
	if c.Id == "" {
	p.linkf("https://%s/%s/+/%s", c.Host, c.Project, c.Ref)
	return
	}

	switch c.Host {
	// This shamelessly hardcodes https://cr-rev.appspot.com/_ah/api/crrev/v1/projects response
	// TODO(nodir): make an RPC and cache on the file system.
	case
	"aomedia.googlesource.com",
	"boringssl.googlesource.com",
	"chromium.googlesource.com",
	"gerrit.googlesource.com",
	"webrtc.googlesource.com":
	p.linkf("https://crrev.com/" + c.Id)
	default:
	p.linkf("https://%s/%s/+/%s", c.Host, c.Project, c.Id)
	}
	if c.Ref != "" {
	p.f(" on %s", c.Ref)
	}
	}

	// change prints cl.
	func (p printer) change(cl pb.GerritChange) {
	switch {
	case cl.Host == "chromium-review.googlesource.com":
	p.linkf("https://crrev.com/c/%d/%d", cl.Change, cl.Patchset)
	case cl.Host == "chrome-internal-review.googlesource.com":
	p.linkf("https://crrev.com/i/%d/%d", cl.Change, cl.Patchset)
	default:
	p.linkf("https://%s/c/%s/+/%d/%d", cl.Host, cl.Project, cl.Change, cl.Patchset)
	}
	}

	// steps print steps.
	func (p printer) steps(steps []pb.Step) {
	maxNameWidth := 0
	for _, s := range steps {
	if w := utf8.RuneCountInString(s.Name); w > maxNameWidth {
	maxNameWidth = w
	}
	}

	for _, s := range steps {
	p.f("%sStep ", ansiStatus[s.Status])
	p.fw(maxNameWidth+5, "%q", s.Name)
	p.fw(10, "%s", s.Status)

	// Print duration.
	durString := ""
	if start := s.StartTime.AsTime(); s.StartTime != nil {
	var stepDur time.Duration
	if end := s.EndTime.AsTime(); s.EndTime != nil {
	stepDur = end.Sub(start)
	} else {
	now := p.nowFn()
	stepDur = now.Sub(start.In(now.Location()))
	}
	durString = truncateDuration(stepDur).String()
	}
	p.fw(10, "%s", durString)

	// Print log names.
	// Do not print log URLs because they are very long and
	// bb has `log` subcommand.
	if len(s.Logs) > 0 {
	p.f("Logs: ")
	for i, l := range s.Logs {
	if i > 0 {
	p.f(", ")
	}
	p.f("%q", l.Name)
	}
	}

	p.f("%s\n", ansi.Reset)

	p.indent.Level += 2
	if s.SummaryMarkdown != "" {
	// TODO(nodir): transform lists of links to look like logs
	p.summary(s.SummaryMarkdown)
	}
	p.indent.Level -= 2
	}
	}

	func (p printer) buildTime(b pb.Build) {
	now := p.nowFn()
	created := readTimestamp(b.CreateTime).In(now.Location())
	started := readTimestamp(b.StartTime).In(now.Location())
	ended := readTimestamp(b.EndTime).In(now.Location())

	if created.IsZero() {
	return
	}
	p.keyword("Created")
	p.f(" ")
	p.dateTime(created)

	// Since the `fields` part of the request is partially controlled by the user,
	// the nil timestamp fields in fetched build aren't trustworthy.
	// So, check by `status` first,which is always set, and only then try to print
	// additional information if semantically fitting.

	if b.Status == pb.Status_SCHEDULED {
	if !p.isJustNow(created) {
	p.f(", ")
	p.keyword("waiting")
	p.f(" for %s, ", truncateDuration(now.Sub(created)))
	}
	return
	}

	if !started.IsZero() {
	p.f(", ")
	p.keyword("waited")
	p.f(" %s, ", truncateDuration(started.Sub(created)))
	p.keyword("started")
	p.f(" ")
	p.time(started)
	}

	if !protoutil.IsEnded(b.Status) {
	if !started.IsZero() {
	// running now
	p.f(", ")
	p.keyword("running")
	p.f(" for %s", truncateDuration(now.Sub(started)))
	}
	} else {
	// ended
	if !started.IsZero() {
	// started in the past
	p.f(", ")
	p.keyword("ran")
	p.f(" for %s", truncateDuration(ended.Sub(started)))
	}
	if !ended.IsZero() {
	p.f(", ")
	p.keyword("ended")
	p.f(" ")
	p.time(ended)
	}
	}
	}

	func (p *printer) summary(summaryMarkdown string) {
	// TODO(nodir): color markdown.
	p.f("%s\n", strings.TrimSpace(summaryMarkdown))
	}

	func (p *printer) dateTime(t time.Time) {
	if p.isJustNow(t) {
	p.f("just now")
	} else {
	p.date(t)
	p.f(" ")
	p.time(t)
	}
	}

	func (p *printer) date(t time.Time) {
	if p.isToday(t) {
	p.f("today")
	} else {
	p.f("on %s", t.Format("2006-01-02"))
	}
	}

	func (p *printer) time(t time.Time) {
	if p.isJustNow(t) {
	p.f("just now")
	} else {
	p.f("at %s", t.Format("15:04:05"))
	}
	}

	func (p *printer) isJustNow(t time.Time) bool {
	now := p.nowFn()
	elapsed := now.Sub(t.In(now.Location()))
	return elapsed > 0 && elapsed < 10*time.Second
	}

	func (p *printer) attr(s string) {
	p.keyword(s)
	p.f(": ")
	}

	func (p *printer) keyword(s string) {
	p.f("%s%s%s", ansiWhiteBold, s, ansi.Reset)
	}

	func (p *printer) linkf(format string, args ...interface{}) {
	p.f("%s", ansiWhiteUnderline)
	p.f(format, args...)
	p.f("%s", ansi.Reset)
	}

	// Error prints the err. If err is a gRPC error, then prints only the message
	// without the code.
	func (p *printer) Error(err error) {
	st, _ := status.FromError(err)
	p.f("%s", st.Message())
	}

	// readTimestamp converts ts to time.Time.
	// Returns zero if ts is invalid.
	func readTimestamp(ts *timestamppb.Timestamp) time.Time {
	if err := ts.CheckValid(); err != nil {
	return time.Time{}
	}
	t := ts.AsTime()
	return t
	}

	func (p *printer) isToday(t time.Time) bool {
	now := p.nowFn()
	nYear, nMonth, nDay := now.Date()
	tYear, tMonth, tDay := t.In(now.Location()).Date()
	return tYear == nYear && tMonth == nMonth && tDay == nDay
	}

	var durTransactions = []struct{ threshold, round time.Duration }{
	{time.Hour, time.Minute},
	{time.Minute, time.Second},
	{time.Second, time.Second / 10},
	{time.Millisecond, time.Millisecond},
	}

	// truncateDuration truncates d to make it more human-readable.
	func truncateDuration(d time.Duration) time.Duration {
	for _, t := range durTransactions {
	if d > t.threshold {
	return d.Round(t.round)
	}
	}
	return d
	}