split oauth_tokens.claims column up; improved fonts; allow multiple sse connections per user; make navbar and use friendly

internal/server/api/sse/router.go

@@ -11,12 +11,16 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
+const (
+	maxNumOpenConnectionsPerUser = 3
+)
+
 type (
 	sseRouter struct {
 		log *logging.Logger
 		sse *sse.Queue
 
-		users map[string]context.CancelFunc
+		users map[string][maxNumOpenConnectionsPerUser]context.CancelFunc
 		lock  sync.Mutex
 	}
 )
@@ -30,7 +34,7 @@ func Routes(
 	s := &sseRouter{
 		log:   logger,
 		sse:   sq,
-		users: make(map[string]context.CancelFunc),
+		users: make(map[string][maxNumOpenConnectionsPerUser]context.CancelFunc),
 	}
 
 	r.GET("/", auth.AuthenticateAndAddIdentityGin(), response.Handler(s.serveEvents))
@@ -46,10 +50,11 @@ func (r *sseRouter) serveEvents(c *gin.Context) (response.Response, error) {
 		"accountID", acctID,
 		"userID", userID,
 		"email", email,
+		"userAgent", c.Request.UserAgent(),
 	)
 	log.Info("user connected to sse queue")
 
-	ctx := r.closeExistingConnectionsForUserAndStoreCancelFuncForUser(c, userID)
+	ctx := r.closeOutstandingConnectionsForUserAndStoreCancelFuncForUser(c, userID)
 
 	w := c.Writer
 
@@ -80,18 +85,34 @@ func (r *sseRouter) serveEvents(c *gin.Context) (response.Response, error) {
 	return response.Status(200), nil
 }
 
-func (r *sseRouter) closeExistingConnectionsForUserAndStoreCancelFuncForUser(ctx context.Context, userID string) context.Context {
+func (r *sseRouter) closeOutstandingConnectionsForUserAndStoreCancelFuncForUser(ctx context.Context, userID string) context.Context {
 	r.lock.Lock()
 	defer r.lock.Unlock()
 
+	ctx, cancel := context.WithCancel(ctx)
+
+	closeConnFuncs := r.users[userID]
+	defer func() {
+		r.users[userID] = closeConnFuncs
+	}()
+
 	// close existing connection
-	if closeConn, ok := r.users[userID]; ok {
-		closeConn()
-		delete(r.users, userID)
+
+	for i := range maxNumOpenConnectionsPerUser {
+		if fn := closeConnFuncs[i]; fn == nil {
+			// not hit limit on connections.
+			// save the cancellation func and done
+			closeConnFuncs[i] = cancel
+			return ctx
+		}
 	}
 
-	// store reference to cancel func
-	ctx, r.users[userID] = context.WithCancel(ctx)
+	// close the oldest connection, shift all cancellation funcs down, and push the new one in
+	closeConnFuncs[0]()
+	for i := range maxNumOpenConnectionsPerUser - 1 {
+		closeConnFuncs[i] = closeConnFuncs[i+1]
+	}
+	closeConnFuncs[maxNumOpenConnectionsPerUser-1] = cancel
 
 	return ctx
 }