dashboard: access config through context

We used to have a single global `config` variable and access it
throughout the whole dashboard application.

However, this approach has been more and more complicated test writing
-- sometimes we want the config to be only slightly different, so that
it's not worth it adding new namespaces, sometimes we have to test how
dashboard handles config changes over time.

This has already led to a number of hacky contextWithXXX methods that
mocked various parts of the global variable. The rest of the code had to
sometimes still use `config` directly and sometimes invoke getXXX(c)
methods. This is very inconsistent and prone to errors.

With more and more situations where we need to patch the config
appearing (see #4118), let's refactor the application to always access
config via the getConfig(c) method. This allows us to uniformly patch
the config and be sure that the non-patched copy is not accessible from
anywhere else.

1 files changed, 23 insertions, 22 deletions

diff --git a/dashboard/app/reporting.go b/dashboard/app/reporting.go
index 27b1fed0b..7c9607249 100644
--- a/dashboard/app/reporting.go
+++ b/dashboard/app/reporting.go
@@ -96,7 +96,7 @@ func handleReportBug(c context.Context, typ string, state *ReportingState, bug *
 func needReport(c context.Context, typ string, state *ReportingState, bug *Bug) (
 	reporting *Reporting, bugReporting *BugReporting, reportingIdx int,
 	status, link string, err error) {
-	reporting, bugReporting, reportingIdx, status, err = currentReporting(bug)
+	reporting, bugReporting, reportingIdx, status, err = currentReporting(c, bug)
 	if err != nil || reporting == nil {
 		return
 	}
@@ -114,7 +114,7 @@ func needReport(c context.Context, typ string, state *ReportingState, bug *Bug)
 		return
 	}
 	ent := state.getEntry(timeNow(c), bug.Namespace, reporting.Name)
-	cfg := config.Namespaces[bug.Namespace]
+	cfg := getConfig(c).Namespaces[bug.Namespace]
 	if timeSince(c, bug.FirstTime) < cfg.ReportingDelay {
 		status = fmt.Sprintf("%v: initial reporting delay", reporting.DisplayTitle)
 		reporting, bugReporting = nil, nil
@@ -187,7 +187,7 @@ func reportingPollNotifications(c context.Context, typ string) []*dashapi.BugNot
 }
 
 func handleReportNotif(c context.Context, typ string, bug *Bug) (*dashapi.BugNotification, error) {
-	reporting, bugReporting, _, _, err := currentReporting(bug)
+	reporting, bugReporting, _, _, err := currentReporting(c, bug)
 	if err != nil || reporting == nil {
 		return nil, nil
 	}
@@ -239,7 +239,7 @@ var notificationGenerators = []func(context.Context, *Bug, *Reporting,
 		if len(bug.Commits) == 0 &&
 			bug.canBeObsoleted(c) &&
 			timeSince(c, bug.LastActivity) > notifyResendPeriod &&
-			timeSince(c, bug.LastTime) > bug.obsoletePeriod() {
+			timeSince(c, bug.LastTime) > bug.obsoletePeriod(c) {
 			log.Infof(c, "%v: obsoleting: %v", bug.Namespace, bug.Title)
 			why := bugObsoletionReason(bug)
 			return createNotification(c, dashapi.BugNotifObsoleted, false, string(why), bug, reporting, bugReporting)
@@ -293,7 +293,7 @@ func createLabelNotification(c context.Context, label BugLabel, bug *Bug, report
 		var err error
 		notif.TreeJobs, err = treeTestJobs(c, bug)
 		if err != nil {
-			log.Errorf(c, "failed to extract jobs for %s: %v", bug.keyHash(), err)
+			log.Errorf(c, "failed to extract jobs for %s: %v", bug.keyHash(c), err)
 			return nil, fmt.Errorf("failed to fetch jobs: %w", err)
 		}
 	}
@@ -331,7 +331,7 @@ func (bug *Bug) canBeObsoleted(c context.Context) bool {
 		return true
 	}
 	if obsoleteWhatWontBeFixBisected {
-		cfg := config.Namespaces[bug.Namespace]
+		cfg := getConfig(c).Namespaces[bug.Namespace]
 		for _, mgr := range bug.HappenedOn {
 			if !cfg.Managers[mgr].FixBisectionDisabled {
 				return false
@@ -342,8 +342,9 @@ func (bug *Bug) canBeObsoleted(c context.Context) bool {
 	return false
 }
 
-func (bug *Bug) obsoletePeriod() time.Duration {
+func (bug *Bug) obsoletePeriod(c context.Context) time.Duration {
 	period := never
+	config := getConfig(c)
 	if config.Obsoleting.MinPeriod == 0 {
 		return period
 	}
@@ -371,7 +372,7 @@ func (bug *Bug) obsoletePeriod() time.Duration {
 		bug.Reporting[len(bug.Reporting)-1].Reported.IsZero() {
 		min, max = config.Obsoleting.NonFinalMinPeriod, config.Obsoleting.NonFinalMaxPeriod
 	}
-	if mgr := bug.managerConfig(); mgr != nil && mgr.ObsoletingMinPeriod != 0 {
+	if mgr := bug.managerConfig(c); mgr != nil && mgr.ObsoletingMinPeriod != 0 {
 		min, max = mgr.ObsoletingMinPeriod, mgr.ObsoletingMaxPeriod
 	}
 	if period < min {
@@ -383,11 +384,11 @@ func (bug *Bug) obsoletePeriod() time.Duration {
 	return period
 }
 
-func (bug *Bug) managerConfig() *ConfigManager {
+func (bug *Bug) managerConfig(c context.Context) *ConfigManager {
 	if len(bug.HappenedOn) != 1 {
 		return nil
 	}
-	mgr := config.Namespaces[bug.Namespace].Managers[bug.HappenedOn[0]]
+	mgr := getConfig(c).Namespaces[bug.Namespace].Managers[bug.HappenedOn[0]]
 	return &mgr
 }
 
@@ -424,7 +425,7 @@ func createNotification(c context.Context, typ dashapi.BugNotif, public bool, te
 	if (public || reporting.moderation) && bugReporting.CC != "" {
 		notif.CC = append(notif.CC, strings.Split(bugReporting.CC, "|")...)
 	}
-	if mgr := bug.managerConfig(); mgr != nil {
+	if mgr := bug.managerConfig(c); mgr != nil {
 		notif.CC = append(notif.CC, mgr.CC.Always...)
 		if public {
 			notif.Maintainers = append(notif.Maintainers, mgr.CC.Maintainers...)
@@ -433,7 +434,7 @@ func createNotification(c context.Context, typ dashapi.BugNotif, public bool, te
 	return notif, nil
 }
 
-func currentReporting(bug *Bug) (*Reporting, *BugReporting, int, string, error) {
+func currentReporting(c context.Context, bug *Bug) (*Reporting, *BugReporting, int, string, error) {
 	if bug.NumCrashes == 0 {
 		// This is possible during the short window when we already created a bug,
 		// but did not attach the first crash to it yet. We need to avoid reporting this bug yet
@@ -446,7 +447,7 @@ func currentReporting(bug *Bug) (*Reporting, *BugReporting, int, string, error)
 		if !bugReporting.Closed.IsZero() {
 			continue
 		}
-		reporting := config.Namespaces[bug.Namespace].ReportingByName(bugReporting.Name)
+		reporting := getConfig(c).Namespaces[bug.Namespace].ReportingByName(bugReporting.Name)
 		if reporting == nil {
 			return nil, nil, 0, "", fmt.Errorf("%v: missing in config", bugReporting.Name)
 		}
@@ -593,7 +594,7 @@ func crashBugReport(c context.Context, bug *Bug, crash *Crash, crashKey *db.Key,
 	if build.Type == BuildFailed {
 		rep.Maintainers = append(rep.Maintainers, kernelRepo.CC.BuildMaintainers...)
 	}
-	if mgr := bug.managerConfig(); mgr != nil {
+	if mgr := bug.managerConfig(c); mgr != nil {
 		rep.CC = append(rep.CC, mgr.CC.Always...)
 		rep.Maintainers = append(rep.Maintainers, mgr.CC.Maintainers...)
 		if build.Type == BuildFailed {
@@ -923,7 +924,7 @@ func checkDupBug(c context.Context, cmd *dashapi.BugUpdate, bug *Bug, bugKey, du
 	if !dupReporting.Closed.IsZero() && dupCanon.Status == BugStatusOpen {
 		return nil, false, "Dup bug is already upstreamed.", nil
 	}
-	if dupCanon.keyHash() == bugKey.StringID() {
+	if dupCanon.keyHash(c) == bugKey.StringID() {
 		return nil, false, "Setting this dup would lead to a bug cycle, cycles are not allowed.", nil
 	}
 	return dup, true, "", nil
@@ -945,7 +946,7 @@ func allowCrossReportingDup(c context.Context, bug, dup *Bug,
 	// provided that these two reportings have the same access level and type.
 	// The rest of the combinations can lead to surprising states and
 	// information hiding, so we don't allow them.
-	cfg := config.Namespaces[bug.Namespace]
+	cfg := getConfig(c).Namespaces[bug.Namespace]
 	bugConfig := &cfg.Reporting[bugIdx]
 	dupConfig := &cfg.Reporting[dupIdx]
 	lastIdx := len(cfg.Reporting) - 1
@@ -1109,7 +1110,7 @@ func incomingCommandCmd(c context.Context, now time.Time, cmd *dashapi.BugUpdate
 	case dashapi.BugStatusDup:
 		bug.Status = BugStatusDup
 		bug.Closed = now
-		bug.DupOf = dup.keyHash()
+		bug.DupOf = dup.keyHash(c)
 	case dashapi.BugStatusUpdate:
 		// Just update Link, Commits, etc below.
 	case dashapi.BugStatusUnCC:
@@ -1188,7 +1189,7 @@ func findDupByTitle(c context.Context, ns, title string) (*Bug, *db.Key, error)
 	if err != nil {
 		return nil, nil, err
 	}
-	bugHash := bugKeyHash(ns, title, seq)
+	bugHash := bugKeyHash(c, ns, title, seq)
 	bugKey := db.NewKey(c, "Bug", bugHash, 0, nil)
 	bug := new(Bug)
 	if err := db.Get(c, bugKey, bug); err != nil {
@@ -1229,7 +1230,7 @@ func lastReportedReporting(bug *Bug) *BugReporting {
 
 // The updateReporting method is supposed to be called both to fully initialize a new
 // Bug object and also to adjust it to the updated namespace configuration.
-func (bug *Bug) updateReportings(cfg *Config, now time.Time) error {
+func (bug *Bug) updateReportings(c context.Context, cfg *Config, now time.Time) error {
 	oldReportings := map[string]BugReporting{}
 	oldPositions := map[string]int{}
 	for i, rep := range bug.Reporting {
@@ -1251,7 +1252,7 @@ func (bug *Bug) updateReportings(cfg *Config, now time.Time) error {
 		} else {
 			bug.Reporting = append(bug.Reporting, BugReporting{
 				Name: rep.Name,
-				ID:   bugReportingHash(bug.keyHash(), rep.Name),
+				ID:   bugReportingHash(bug.keyHash(c), rep.Name),
 			})
 		}
 	}
@@ -1351,7 +1352,7 @@ func (state *ReportingState) getEntry(now time.Time, namespace, name string) *Re
 
 func loadFullBugInfo(c context.Context, bug *Bug, bugKey *db.Key,
 	bugReporting *BugReporting) (*dashapi.FullBugInfo, error) {
-	reporting := config.Namespaces[bug.Namespace].ReportingByName(bugReporting.Name)
+	reporting := getConfig(c).Namespaces[bug.Namespace].ReportingByName(bugReporting.Name)
 	if reporting == nil {
 		return nil, fmt.Errorf("failed to find the reporting object")
 	}
@@ -1383,7 +1384,7 @@ func loadFullBugInfo(c context.Context, bug *Bug, bugKey *db.Key,
 		return nil, err
 	}
 	for _, similarBug := range similar {
-		_, bugReporting, _, _, _ := currentReporting(similarBug)
+		_, bugReporting, _, _, _ := currentReporting(c, similarBug)
 		if bugReporting == nil {
 			continue
 		}