tools: Add the 'cts time' sub-command

Add the common utilities for starting and fetching build results.

'cts time' provides views on the longest running tests, along with
a histogram view of all test times.

Bug: dawn:1342
Change-Id: Ia3707f7f062ea26a2406e3163a26e1cc7e30e3b2
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/88319
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>

go.mod

@@ -27,8 +27,10 @@ require (
 	github.com/klauspost/compress v1.13.5 // indirect
 	github.com/kr/pretty v0.3.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/maruel/subcommands v1.1.0 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
 	github.com/rogpeppe/go-internal v1.8.0 // indirect
+	github.com/texttheater/golang-levenshtein v1.0.1 // indirect
 	github.com/tklauser/go-sysconf v0.3.10 // indirect
 	github.com/tklauser/numcpus v0.4.0 // indirect
 	github.com/yusufpapurcu/wmi v1.2.2 // indirect

go.sum

@@ -337,7 +337,9 @@ github.com/lann/ps v0.0.0-20150810152359-62de8c46ede0/go.mod h1:vmVJ0l/dxyfGW6Fm
 github.com/luci/gtreap v0.0.0-20161228054646-35df89791e8f/go.mod h1:OjKOY0UvVOOH5nWXSIWTbQWESn8dDiGlaEZx6IAsWhU=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/magiconair/properties v1.8.1/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
+github.com/maruel/subcommands v1.1.0 h1:5k7Y1KXDrI4U2Q7J6R7rbnpoNAiklUDTdaK2fFT998g=
 github.com/maruel/subcommands v1.1.0/go.mod h1:b25AG9Eho2Rs1NUPAPAYBFy1B5y63QMxw/2WmLGO8m8=
+github.com/maruel/ut v1.0.2 h1:mQTlQk3jubTbdTcza+hwoZQWhzcvE4L6K6RTtAFlA1k=
 github.com/maruel/ut v1.0.2/go.mod h1:RV8PwPD9dd2KFlnlCc/DB2JVvkXmyaalfc5xvmSrRSs=
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-colorable v0.1.4/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
@@ -455,6 +457,7 @@ github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/subosito/gotenv v1.2.0/go.mod h1:N0PQaV/YGNqwC0u51sEeR/aUtSLEXKX9iv69rRypqCw=
+github.com/texttheater/golang-levenshtein v1.0.1 h1:+cRNoVrfiwufQPhoMzB6N0Yf/Mqajr6t1lOv8GyGE2U=
 github.com/texttheater/golang-levenshtein v1.0.1/go.mod h1:PYAKrbF5sAiq9wd+H82hs7gNaen0CplQ9uvm6+enD/8=
 github.com/tidwall/jsonc v0.3.2 h1:ZTKrmejRlAJYdn0kcaFqRAKlxxFIC21pYq8vLa4p2Wc=
 github.com/tidwall/jsonc v0.3.2/go.mod h1:dw+3CIxqHi+t8eFSpzzMlcVYxKp08UP5CD8/uSFCyJE=

tools/src/cmd/cts/common/build.go

@@ -0,0 +1,157 @@
+// Copyright 2022 The Dawn 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 common
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"sort"
+	"time"
+
+	"dawn.googlesource.com/dawn/tools/src/buildbucket"
+	"dawn.googlesource.com/dawn/tools/src/gerrit"
+)
+
+// BuildsByName is a map of builder name to build result
+type BuildsByName map[string]buildbucket.Build
+
+func (b BuildsByName) ids() []buildbucket.BuildID {
+	ids := make([]buildbucket.BuildID, 0, len(b))
+	for _, build := range b {
+		ids = append(ids, build.ID)
+	}
+	return ids
+}
+
+// GetBuilds returns the builds, as declared in the config file, for the given
+// patchset
+func GetBuilds(
+	ctx context.Context,
+	cfg Config,
+	ps gerrit.Patchset,
+	bb *buildbucket.Buildbucket) (BuildsByName, error) {
+
+	builds := BuildsByName{}
+
+	err := bb.SearchBuilds(ctx, ps, func(build buildbucket.Build) error {
+		for name, builder := range cfg.Builders {
+			if build.Builder == builder {
+				builds[name] = build
+				break
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return builds, err
+}
+
+// WaitForBuildsToComplete waits until all the provided builds have finished.
+func WaitForBuildsToComplete(
+	ctx context.Context,
+	cfg Config,
+	ps gerrit.Patchset,
+	bb *buildbucket.Buildbucket,
+	builds BuildsByName) error {
+
+	buildsStillRunning := func() []string {
+		out := []string{}
+		for name, build := range builds {
+			if build.Status.Running() {
+				out = append(out, name)
+			}
+		}
+		sort.Strings(out)
+		return out
+	}
+
+	for {
+		// Refresh build status
+		for name, build := range builds {
+			build, err := bb.QueryBuild(ctx, build.ID)
+			if err != nil {
+				return fmt.Errorf("failed to query build for '%v': %w", name, err)
+			}
+			builds[name] = build
+		}
+		running := buildsStillRunning()
+		if len(running) == 0 {
+			break
+		}
+		log.Println("waiting for builds to complete: ", running)
+		time.Sleep(time.Minute * 2)
+	}
+
+	for name, build := range builds {
+		if build.Status == buildbucket.StatusInfraFailure ||
+			build.Status == buildbucket.StatusCanceled {
+			return fmt.Errorf("%v builder failed with %v", name, build.Status)
+		}
+	}
+
+	return nil
+}
+
+// GetOrStartBuildsAndWait starts the builds as declared in the config file,
+// for the given patchset, if they haven't already been started or if retest is
+// true. GetOrStartBuildsAndWait then waits for the builds to complete, and then
+// returns the results.
+func GetOrStartBuildsAndWait(
+	ctx context.Context,
+	cfg Config,
+	ps gerrit.Patchset,
+	bb *buildbucket.Buildbucket,
+	retest bool) (BuildsByName, error) {
+
+	builds := BuildsByName{}
+
+	if !retest {
+		// Find any existing builds for the patchset
+		err := bb.SearchBuilds(ctx, ps, func(build buildbucket.Build) error {
+			for name, builder := range cfg.Builders {
+				if build.Builder == builder {
+					builds[name] = build
+					break
+				}
+			}
+			return nil
+		})
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// Kick any missing builds
+	for name, builder := range cfg.Builders {
+		if _, existing := builds[name]; !existing {
+			build, err := bb.StartBuild(ctx, ps, builder, retest)
+			if err != nil {
+				return nil, err
+			}
+			log.Printf("started build: %+v", build)
+			builds[name] = build
+		}
+	}
+
+	if err := WaitForBuildsToComplete(ctx, cfg, ps, bb, builds); err != nil {
+		return nil, err
+	}
+
+	return builds, nil
+}

tools/src/cmd/cts/common/constants.go

@@ -0,0 +1,37 @@
+// Copyright 2022 The Dawn 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 common
+
+import (
+	"dawn.googlesource.com/dawn/tools/src/utils"
+	"go.chromium.org/luci/auth"
+	"go.chromium.org/luci/hardcoded/chromeinfra"
+)
+
+const (
+	// RollSubjectPrefix is the subject prefix for CTS roll changes
+	RollSubjectPrefix = "Roll third_party/webgpu-cts/ "
+
+	// DefaultCacheDir is the default directory for the results cache
+	DefaultCacheDir = "~/.cache/webgpu-cts-results"
+)
+
+// DefaultAuthOptions returns the default authentication options for use by
+// command line arguments.
+func DefaultAuthOptions() auth.Options {
+	def := chromeinfra.DefaultAuthOptions()
+	def.SecretsDir = utils.ExpandHome("~/.config/dawn-cts")
+	return def
+}

tools/src/cmd/cts/common/results.go

@@ -0,0 +1,349 @@
+// Copyright 2022 The Dawn 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 common
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	"dawn.googlesource.com/dawn/tools/src/buildbucket"
+	"dawn.googlesource.com/dawn/tools/src/cts/query"
+	"dawn.googlesource.com/dawn/tools/src/cts/result"
+	"dawn.googlesource.com/dawn/tools/src/gerrit"
+	"dawn.googlesource.com/dawn/tools/src/resultsdb"
+	"dawn.googlesource.com/dawn/tools/src/subcmd"
+	"dawn.googlesource.com/dawn/tools/src/utils"
+	"go.chromium.org/luci/auth"
+	rdbpb "go.chromium.org/luci/resultdb/proto/v1"
+)
+
+// ResultSource describes the source of CTS test results.
+// ResultSource is commonly used by command line flags for specifying from
+// where the results should be loaded / fetched.
+// If neither File or Patchset are specified, then results will be fetched from
+// the last successful CTS roll.
+type ResultSource struct {
+	// The directory used to cache results fetched from ResultDB
+	CacheDir string
+	// If specified, results will be loaded from this file path
+	// Must not be specified if Patchset is also specified.
+	File string
+	// If specified, results will be fetched from this gerrit patchset
+	// Must not be specified if File is also specified.
+	Patchset gerrit.Patchset
+}
+
+// RegisterFlags registers the ResultSource fields as commandline flags for use
+// by command line tools.
+func (r *ResultSource) RegisterFlags(cfg Config) {
+	flag.StringVar(&r.CacheDir, "cache", DefaultCacheDir, "path to the results cache")
+	flag.StringVar(&r.File, "results", "", "local results.txt file (mutually exclusive with --cl)")
+	r.Patchset.RegisterFlags(cfg.Gerrit.Host, cfg.Gerrit.Project)
+}
+
+// GetResults loads or fetches the results, based on the values of r.
+func (r *ResultSource) GetResults(ctx context.Context, cfg Config, auth auth.Options) (result.List, error) {
+	// Check that File and Patchset weren't both specified
+	ps := r.Patchset
+	if r.File != "" && ps.Change != 0 {
+		fmt.Fprintln(flag.CommandLine.Output(), "only one of --results and --cl can be specified")
+		return nil, subcmd.ErrInvalidCLA
+	}
+
+	// If a file was specified, then load that.
+	if r.File != "" {
+		return result.Load(r.File)
+	}
+
+	// Initialize the buildbucket and resultdb clients
+	bb, err := buildbucket.New(ctx, auth)
+	if err != nil {
+		return nil, err
+	}
+	rdb, err := resultsdb.New(ctx, auth)
+	if err != nil {
+		return nil, err
+	}
+
+	// If no change was specified, then pull the results from the most recent
+	// CTS roll.
+	if ps.Change == 0 {
+		fmt.Println("no change specified, scanning gerrit for last CTS roll...")
+		gerrit, err := gerrit.New(cfg.Gerrit.Host, gerrit.Credentials{})
+		if err != nil {
+			return nil, err
+		}
+		latest, err := LatestCTSRoll(gerrit)
+		if err != nil {
+			return nil, err
+		}
+		results, ps, err := MostRecentResultsForChange(ctx, cfg, r.CacheDir, gerrit, bb, rdb, latest.Number)
+		if err != nil {
+			return nil, err
+		}
+		fmt.Printf("using results from cl %v ps %v...\n", ps.Change, ps.Patchset)
+		return results, nil
+	}
+
+	// If a change, but no patchset was specified, then query the most recent
+	// patchset.
+	if ps.Patchset == 0 {
+		gerrit, err := gerrit.New(cfg.Gerrit.Host, gerrit.Credentials{})
+		if err != nil {
+			return nil, err
+		}
+		ps, err := gerrit.LatestPatchest(strconv.Itoa(ps.Change))
+		if err != nil {
+			err := fmt.Errorf("failed to find latest patchset of change %v: %w",
+				ps.Change, err)
+			return nil, err
+		}
+	}
+
+	// Obtain the patchset's results, kicking a build if there are no results
+	// already available.
+	log.Printf("fetching results from cl %v ps %v...", ps.Change, ps.Patchset)
+	builds, err := GetOrStartBuildsAndWait(ctx, cfg, ps, bb, false)
+	if err != nil {
+		return nil, err
+	}
+
+	results, err := CacheResults(ctx, cfg, ps, r.CacheDir, rdb, builds)
+	if err != nil {
+		return nil, err
+	}
+
+	return results, nil
+}
+
+// CacheResults looks in the cache at 'cacheDir' for the results for the given
+// patchset. If the cache contains the results, then these are loaded and
+// returned. If the cache does not contain the results, then they are fetched
+// using GetResults(), saved to the cache directory and are returned.
+func CacheResults(
+	ctx context.Context,
+	cfg Config,
+	ps gerrit.Patchset,
+	cacheDir string,
+	rdb *resultsdb.ResultsDB,
+	builds BuildsByName) (result.List, error) {
+
+	var cachePath string
+	if cacheDir != "" {
+		dir := utils.ExpandHome(cacheDir)
+		path := filepath.Join(dir, strconv.Itoa(ps.Change), fmt.Sprintf("ps-%v.txt", ps.Patchset))
+		if _, err := os.Stat(path); err == nil {
+			return result.Load(path)
+		}
+		cachePath = path
+	}
+
+	results, err := GetResults(ctx, cfg, rdb, builds)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := result.Save(cachePath, results); err != nil {
+		log.Println("failed to save results to cache: %w", err)
+	}
+
+	return results, nil
+}
+
+// GetResults fetches the build results from ResultDB.
+// GetResults does not trigger new builds.
+func GetResults(
+	ctx context.Context,
+	cfg Config,
+	rdb *resultsdb.ResultsDB,
+	builds BuildsByName) (result.List, error) {
+
+	fmt.Printf("fetching results from resultdb...")
+
+	lastPrintedDot := time.Now()
+
+	toStatus := func(s rdbpb.TestStatus) result.Status {
+		switch s {
+		default:
+			return result.Unknown
+		case rdbpb.TestStatus_PASS:
+			return result.Pass
+		case rdbpb.TestStatus_FAIL:
+			return result.Failure
+		case rdbpb.TestStatus_CRASH:
+			return result.Crash
+		case rdbpb.TestStatus_ABORT:
+			return result.Abort
+		case rdbpb.TestStatus_SKIP:
+			return result.Skip
+		}
+	}
+
+	results := result.List{}
+	err := rdb.QueryTestResults(ctx, builds.ids(), cfg.Test.Prefix+".*", func(rpb *rdbpb.TestResult) error {
+		if time.Since(lastPrintedDot) > 5*time.Second {
+			lastPrintedDot = time.Now()
+			fmt.Printf(".")
+		}
+
+		if !strings.HasPrefix(rpb.GetTestId(), cfg.Test.Prefix) {
+			return nil
+		}
+
+		testName := rpb.GetTestId()[len(cfg.Test.Prefix):]
+		status := toStatus(rpb.Status)
+		tags := result.NewTags()
+
+		for _, sp := range rpb.Tags {
+			if sp.Key == "typ_tag" {
+				tags.Add(sp.Value)
+			}
+		}
+
+		if fr := rpb.GetFailureReason(); fr != nil {
+			if strings.Contains(fr.GetPrimaryErrorMessage(), "asyncio.exceptions.TimeoutError") {
+				status = result.Slow
+			}
+		}
+
+		duration := rpb.GetDuration().AsDuration()
+		if status == result.Pass && duration > cfg.Test.SlowThreshold {
+			status = result.Slow
+		}
+
+		results = append(results, result.Result{
+			Query:    query.Parse(testName),
+			Status:   status,
+			Tags:     tags,
+			Duration: duration,
+		})
+
+		return nil
+	})
+
+	fmt.Println(" done")
+
+	if err != nil {
+		return nil, err
+	}
+
+	// Expand any aliased tags
+	ExpandAliasedTags(cfg, results)
+
+	// Remove any duplicates from the results.
+	results = results.ReplaceDuplicates(result.Deduplicate)
+
+	results.Sort()
+	return results, err
+}
+
+// LatestCTSRoll returns for the latest merged CTS roll that landed in the past
+// month. If no roll can be found, then an error is returned.
+func LatestCTSRoll(g *gerrit.Gerrit) (gerrit.ChangeInfo, error) {
+	changes, _, err := g.QueryChanges(
+		`status:merged`,
+		`-age:1month`,
+		fmt.Sprintf(`message:"%v"`, RollSubjectPrefix))
+	if err != nil {
+		return gerrit.ChangeInfo{}, err
+	}
+	if len(changes) == 0 {
+		return gerrit.ChangeInfo{}, fmt.Errorf("no change found")
+	}
+	sort.Slice(changes, func(i, j int) bool {
+		return changes[i].Submitted.Time.After(changes[j].Submitted.Time)
+	})
+	return changes[0], nil
+}
+
+// LatestPatchset returns the most recent patchset for the given change.
+func LatestPatchset(g *gerrit.Gerrit, change int) (gerrit.Patchset, error) {
+	ps, err := g.LatestPatchest(strconv.Itoa(change))
+	if err != nil {
+		err := fmt.Errorf("failed to find latest patchset of change %v: %w",
+			ps.Change, err)
+		return gerrit.Patchset{}, err
+	}
+	return ps, nil
+}
+
+// MostRecentResultsForChange returns the results from the most recent patchset
+// that has build results. If no results can be found for the entire change,
+// then an error is returned.
+func MostRecentResultsForChange(
+	ctx context.Context,
+	cfg Config,
+	cacheDir string,
+	g *gerrit.Gerrit,
+	bb *buildbucket.Buildbucket,
+	rdb *resultsdb.ResultsDB,
+	change int) (result.List, gerrit.Patchset, error) {
+
+	ps, err := LatestPatchset(g, change)
+	if err != nil {
+		return nil, gerrit.Patchset{}, nil
+	}
+
+	for ps.Patchset > 0 {
+		builds, err := GetBuilds(ctx, cfg, ps, bb)
+		if err != nil {
+			return nil, gerrit.Patchset{}, err
+		}
+		if len(builds) > 0 {
+			if err := WaitForBuildsToComplete(ctx, cfg, ps, bb, builds); err != nil {
+				return nil, gerrit.Patchset{}, err
+			}
+
+			results, err := CacheResults(ctx, cfg, ps, cacheDir, rdb, builds)
+			if err != nil {
+				return nil, gerrit.Patchset{}, err
+			}
+
+			if len(results) > 0 {
+				return results, ps, nil
+			}
+		}
+		ps.Patchset--
+	}
+
+	return nil, gerrit.Patchset{}, fmt.Errorf("no builds found for change %v", change)
+}
+
+// ExpandAliasedTags modifies each result so that tags which are found in
+// cfg.TagAliases are expanded to include all the tag aliases.
+// This is bodge for crbug.com/dawn/1387.
+func ExpandAliasedTags(cfg Config, results result.List) {
+	// Build the result sets
+	sets := make([]result.Tags, len(cfg.TagAliases))
+	for i, l := range cfg.TagAliases {
+		sets[i] = result.NewTags(l...)
+	}
+	// Expand the result tags for the aliased tag sets
+	for _, r := range results {
+		for _, set := range sets {
+			if r.Tags.ContainsAny(set) {
+				r.Tags.AddAll(set)
+			}
+		}
+	}
+}

tools/src/cmd/cts/main.go

@@ -29,6 +29,7 @@ import (
 
 	// Register sub-commands
 	_ "dawn.googlesource.com/dawn/tools/src/cmd/cts/format"
+	_ "dawn.googlesource.com/dawn/tools/src/cmd/cts/time"
 )
 
 func main() {

tools/src/cmd/cts/time/time.go

@@ -0,0 +1,148 @@
+// Copyright 2022 The Dawn 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 time
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"math"
+	"sort"
+	"time"
+
+	"dawn.googlesource.com/dawn/tools/src/cmd/cts/common"
+	"dawn.googlesource.com/dawn/tools/src/cts/result"
+	"dawn.googlesource.com/dawn/tools/src/subcmd"
+	"go.chromium.org/luci/auth/client/authcli"
+)
+
+func init() {
+	common.Register(&cmd{})
+}
+
+type cmd struct {
+	flags struct {
+		source    common.ResultSource
+		auth      authcli.Flags
+		tags      string
+		topN      int
+		histogram bool
+	}
+}
+
+func (cmd) Name() string {
+	return "time"
+}
+
+func (cmd) Desc() string {
+	return "displays timing information for tests"
+}
+
+func (c *cmd) RegisterFlags(ctx context.Context, cfg common.Config) ([]string, error) {
+	c.flags.source.RegisterFlags(cfg)
+	c.flags.auth.Register(flag.CommandLine, common.DefaultAuthOptions())
+	flag.IntVar(&c.flags.topN, "top", 0, "print the top N slowest tests")
+	flag.BoolVar(&c.flags.histogram, "histogram", false, "print a histogram of test timings")
+	flag.StringVar(&c.flags.tags, "tags", "", "comma-separated list of tags to filter results")
+	return nil, nil
+}
+
+func (c *cmd) Run(ctx context.Context, cfg common.Config) error {
+	// Validate command line arguments
+	auth, err := c.flags.auth.Options()
+	if err != nil {
+		return fmt.Errorf("failed to obtain authentication options: %w", err)
+	}
+
+	// Obtain the results
+	results, err := c.flags.source.GetResults(ctx, cfg, auth)
+	if err != nil {
+		return err
+	}
+
+	if len(results) == 0 {
+		return fmt.Errorf("no results found")
+	}
+
+	// If tags were provided, filter the results to those that contain these tags
+	if c.flags.tags != "" {
+		results = results.FilterByTags(result.StringToTags(c.flags.tags))
+		if len(results) == 0 {
+			return fmt.Errorf("no results after filtering by tags")
+		}
+	}
+
+	// Sort the results with longest duration first
+	sort.Slice(results, func(i, j int) bool {
+		return results[i].Duration > results[j].Duration
+	})
+
+	didSomething := false
+
+	// Did the user request --top N ?
+	if c.flags.topN > 0 {
+		didSomething = true
+		topN := results
+		if c.flags.topN < len(results) {
+			topN = topN[:c.flags.topN]
+		}
+		for i, r := range topN {
+			fmt.Printf("%3.1d: %v\n", i, r)
+		}
+	}
+
+	// Did the user request --histogram ?
+	if c.flags.histogram {
+		maxTime := results[0].Duration
+
+		const (
+			numBins = 25
+			pow     = 2.0
+		)
+
+		binToDuration := func(i int) time.Duration {
+			frac := math.Pow(float64(i)/float64(numBins), pow)
+			return time.Duration(float64(maxTime) * frac)
+		}
+		durationToBin := func(d time.Duration) int {
+			frac := math.Pow(float64(d)/float64(maxTime), 1.0/pow)
+			idx := int(frac * numBins)
+			if idx >= numBins-1 {
+				return numBins - 1
+			}
+			return idx
+		}
+
+		didSomething = true
+		bins := make([]int, numBins)
+		for _, r := range results {
+			idx := durationToBin(r.Duration)
+			bins[idx] = bins[idx] + 1
+		}
+		for i, bin := range bins {
+			fmt.Printf("[%.8v, %.8v]: %v\n", binToDuration(i), binToDuration(i+1), bin)
+		}
+	}
+
+	// If the user didn't request anything, show a helpful message
+	if !didSomething {
+		fmt.Fprintln(flag.CommandLine.Output(), "no action flags specified for", c.Name())
+		fmt.Fprintln(flag.CommandLine.Output())
+		flag.Usage()
+		return subcmd.ErrInvalidCLA
+	}
+
+	return nil
+}