added shim to allow test to pass while server is updated

nats-base-client/kv.ts

@@ -251,7 +251,7 @@ export class Bucket implements KV {
     await this.js.publish(this.subjectForKey(k), Empty, { headers: h });
   }
 
-  consumerOn(k: string, lastOnly = false): Promise<ConsumerInfo> {
+  async consumerOn(k: string, lastOnly = false): Promise<ConsumerInfo> {
     const ji = this.js as JetStreamClientImpl;
     const nc = ji.nc;
     const inbox = createInbox(nc.options.inboxPrefix);
@@ -264,8 +264,24 @@ export class Bucket implements KV {
       "filter_subject": this.subjectForKey(k),
       "flow_control": k === "*",
     };
-
-    return this.jsm.consumers.add(this.stream, opts);
+    try {
+      const ci = await this.jsm.consumers.add(this.stream, opts);
+      return ci;
+    } catch (err) {
+      if (
+        err.message === "invalid json" &&
+        opts.deliver_policy === DeliverPolicy.LastPerSubject
+      ) {
+        // FIXME: this here while supported server becomes available
+        console.error(
+          `\u001B[33m KV feature running on a non-supported server  \u001B[0m`,
+        );
+        opts.deliver_policy = DeliverPolicy.Last;
+        return await this.jsm.consumers.add(this.stream, opts);
+      } else {
+        throw err;
+      }
+    }
   }
 
   async history(k: string): Promise<QueuedIterator<Entry>> {