Priority Bidder Ejection

config/config.go

@@ -944,6 +944,8 @@ func SetupViper(v *viper.Viper, filename string, bidderInfos BidderInfos) {
 
 	v.SetDefault("event.timeout_ms", 1000)
 
+	v.SetDefault("user_sync.priority_groups", [][]string{})
+
 	v.SetDefault("accounts.filesystem.enabled", false)
 	v.SetDefault("accounts.filesystem.directorypath", "./stored_requests/data/by_id")
 	v.SetDefault("accounts.in_memory_cache.type", "none")

config/usersync.go

@@ -2,13 +2,13 @@ package config
 
 // UserSync specifies the static global user sync configuration.
 type UserSync struct {
-	Cooperative UserSyncCooperative `mapstructure:"coop_sync"`
-	ExternalURL string              `mapstructure:"external_url"`
-	RedirectURL string              `mapstructure:"redirect_url"`
+	Cooperative    UserSyncCooperative `mapstructure:"coop_sync"`
+	ExternalURL    string              `mapstructure:"external_url"`
+	RedirectURL    string              `mapstructure:"redirect_url"`
+	PriorityGroups [][]string          `mapstructure:"priority_groups"`
 }
 
 // UserSyncCooperative specifies the static global default cooperative cookie sync
 type UserSyncCooperative struct {
-	EnabledByDefault bool       `mapstructure:"default"`
-	PriorityGroups   [][]string `mapstructure:"priority_groups"`
+	EnabledByDefault bool `mapstructure:"default"`
 }

endpoints/cookie_sync.go

@@ -39,6 +39,7 @@ var (
 	errCookieSyncAccountBlocked                    = errors.New("account is disabled, please reach out to the prebid server host")
 	errCookieSyncAccountConfigMalformed            = errors.New("account config is malformed and could not be read")
 	errCookieSyncAccountInvalid                    = errors.New("account must be valid if provided, please reach out to the prebid server host")
+	errSyncerIsNotPriority                         = errors.New("syncer key is not a priority, and there are only priority elements left")
 )
 
 var cookieSyncBidderFilterAllowAll = usersync.NewUniformBidderFilter(usersync.BidderFilterModeInclude)
@@ -168,7 +169,7 @@ func (c *cookieSyncEndpoint) parseRequest(r *http.Request) (usersync.Request, pr
 		Bidders: request.Bidders,
 		Cooperative: usersync.Cooperative{
 			Enabled:        (request.CooperativeSync != nil && *request.CooperativeSync) || (request.CooperativeSync == nil && c.config.UserSync.Cooperative.EnabledByDefault),
-			PriorityGroups: c.config.UserSync.Cooperative.PriorityGroups,
+			PriorityGroups: c.config.UserSync.PriorityGroups,
 		},
 		Limit: request.Limit,
 		Privacy: usersyncPrivacy{

endpoints/cookie_sync_test.go

@@ -516,9 +516,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: false,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{
@@ -563,9 +563,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: false,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{
@@ -616,9 +616,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: true,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},
@@ -642,9 +642,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: false,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},
@@ -668,9 +668,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: true,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},
@@ -694,9 +694,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: false,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},
@@ -720,9 +720,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: true,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},
@@ -746,9 +746,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: false,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},
@@ -889,9 +889,8 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
-				Cooperative: config.UserSyncCooperative{
-					PriorityGroups: [][]string{{"a", "b", "c"}},
-				},
+				PriorityGroups: [][]string{{"a", "b", "c"}},
+				Cooperative:    config.UserSyncCooperative{},
 			},
 			expectedPrivacy: privacy.Policies{},
 			expectedRequest: usersync.Request{
@@ -919,9 +918,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: false,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},
@@ -950,9 +949,9 @@ func TestCookieSyncParseRequest(t *testing.T) {
 			givenGDPRConfig:  config.GDPR{Enabled: true, DefaultValue: "0"},
 			givenCCPAEnabled: true,
 			givenConfig: config.UserSync{
+				PriorityGroups: [][]string{{"a", "b", "c"}},
 				Cooperative: config.UserSyncCooperative{
 					EnabledByDefault: false,
-					PriorityGroups:   [][]string{{"a", "b", "c"}},
 				},
 			},
 			expectedPrivacy: privacy.Policies{},

endpoints/setuid.go

@@ -159,14 +159,25 @@ func NewSetUIDEndpoint(cfg *config.Configuration, syncersByBidder map[string]use
 
 		setSiteCookie := siteCookieCheck(r.UserAgent())
 
+		// Priority Ejector Set Up
+		priorityEjector := &usersync.PriorityBidderEjector{PriorityGroups: cfg.UserSync.PriorityGroups, TieEjector: &usersync.OldestEjector{}, SyncersByBidder: syncersByBidder}
+		priorityEjector.IsSyncerPriority = isSyncerPriority(bidderName, cfg.UserSync.PriorityGroups)
+
 		// Write Cookie
-		encodedCookie, err := cookie.PrepareCookieForWrite(&cfg.HostCookie, encoder)
+		encodedCookie, err := cookie.PrepareCookieForWrite(&cfg.HostCookie, encoder, priorityEjector)
 		if err != nil {
-			w.WriteHeader(http.StatusBadRequest)
-			metricsEngine.RecordSetUid(metrics.SetUidBadRequest)
-			so.Errors = []error{err}
-			so.Status = http.StatusBadRequest
-			return
+			if err.Error() == errSyncerIsNotPriority.Error() {
+				w.WriteHeader(http.StatusOK)
+				w.Write([]byte("Warning: " + err.Error() + ", cookie not updated"))
+				so.Status = http.StatusOK
+				return
+			} else {
+				w.WriteHeader(http.StatusBadRequest)
+				metricsEngine.RecordSetUid(metrics.SetUidBadRequest)
+				so.Errors = []error{err}
+				so.Status = http.StatusBadRequest
+				return
+			}
 		}
 		usersync.WriteCookie(w, encodedCookie, &cfg.HostCookie, setSiteCookie)
 
@@ -330,6 +341,17 @@ func getSyncer(query url.Values, syncersByBidder map[string]usersync.Syncer) (us
 	return syncer, bidder, nil
 }
 
+func isSyncerPriority(bidderNameFromSyncerQuery string, priorityGroups [][]string) bool {
+	for _, group := range priorityGroups {
+		for _, bidder := range group {
+			if bidderNameFromSyncerQuery == bidder {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 // getResponseFormat reads the format query parameter or falls back to the syncer's default.
 // Returns either "b" (iframe), "i" (redirect), or an empty string "" (legacy behavior of an
 // empty response body with no content type).