Fix net::ERR_INSUFFICIENT_RESOURCES errors on HTTP2 introduced in 5.4.1 (#415)

Author: jvigliotta

src/persistence/BaseMCWSPersistenceProvider.js

@@ -59,15 +59,25 @@ export default class BaseMCWSPersistenceProvider {
    * @returns {Promise.<NamespaceDefinition[]>} persistenceNamespaces
    */
   async getPersistenceNamespaces() {
-    // get root namespaces, get contained namespaces.
-    if (!this.persistenceNamespaces) {
-      const rootNamespaces = await this.getRootNamespaces();
-      const allContainedNamespaces = await this.getAllContainedNamespaces(rootNamespaces);
+    // Return cached result if available
+    if (this.persistenceNamespaces) {
+      return this.persistenceNamespaces;
+    }
+
+    // If initialization is in progress, wait for it
+    if (!this.persistenceNamespacesPromise) {
+      this.persistenceNamespacesPromise = (async () => {
+        const rootNamespaces = await this.getRootNamespaces();
+        const allContainedNamespaces = await this.getAllContainedNamespaces(rootNamespaces);
+
+        this.persistenceNamespaces = [...rootNamespaces, ...allContainedNamespaces];
+        delete this.persistenceNamespacesPromise;
 
-      this.persistenceNamespaces = [...rootNamespaces, ...allContainedNamespaces];
+        return this.persistenceNamespaces;
+      })();
     }
 
-    return this.persistenceNamespaces;
+    return this.persistenceNamespacesPromise;
   }
 
   /**

src/services/mcws/MCWSClient.js

@@ -60,9 +60,6 @@ class MCWSClient {
       delete options.params;
     }
 
-    // Keepalive
-    options.keepalive = true;
-
     try {
       response = await fetch(url, options);
     } catch (error) {