Add a mutex to org-channel map in off-thread org monitor

A concurrent read and write (or just concurrent writes) panic with the map between org IDs and channels for monitoring quota for the org can happen when several requests to APIs belonging to the same organisation occur at the same time and there's no mapping yet. This is pretty easy to reproduce by launching a lot of simultaneus requests right before the gateway starts (e.g. with ab tool).

In addition to this, tyk.with_dash.conf template now ships with off-thread org processing disabled as there's no org session by default in on-prem installations.

install/data/tyk.with_dash.conf

@@ -54,7 +54,7 @@
   "close_connections": true,
   "enable_non_transactional_rate_limiter": true,
   "enable_sentinel_rate_limiter": false,
-  "experimental_process_org_off_thread": true,
+  "experimental_process_org_off_thread": false,
   "local_session_cache": {
     "disable_cached_session_state": false
   },

mw_organisation_activity.go

@@ -9,8 +9,12 @@ import (
 	"github.com/TykTechnologies/tyk/config"
 )
 
-var orgChanMap = make(map[string]chan bool)
+type orgChanMapMu struct {
+	sync.Mutex
+	channels map[string](chan bool)
+}
 
+var orgChanMap = orgChanMapMu{channels: map[string](chan bool){}}
 var orgActiveMap sync.Map
 
 // RateLimitAndQuotaCheck will check the incomming request and key whether it is within it's quota and
@@ -104,13 +108,14 @@ func (k *OrganizationMonitor) SetOrgSentinel(orgChan chan bool, orgId string) {
 }
 
 func (k *OrganizationMonitor) ProcessRequestOffThread(r *http.Request) (error, int) {
-
-	orgChan, ok := orgChanMap[k.Spec.OrgID]
+	orgChanMap.Lock()
+	orgChan, ok := orgChanMap.channels[k.Spec.OrgID]
 	if !ok {
-		orgChanMap[k.Spec.OrgID] = make(chan bool)
-		orgChan = orgChanMap[k.Spec.OrgID]
+		orgChan = make(chan bool)
+		orgChanMap.channels[k.Spec.OrgID] = orgChan
 		go k.SetOrgSentinel(orgChan, k.Spec.OrgID)
 	}
+	orgChanMap.Unlock()
 	active, found := orgActiveMap.Load(k.Spec.OrgID)
 
 	go k.AllowAccessNext(orgChan, r.URL.Path, requestIP(r), r)