enable push handler support to be tested / test it

packages/client/lib/client/commands-queue.ts

@@ -52,7 +52,7 @@ export default class RedisCommandsQueue {
   readonly decoder;
   readonly #pubSub = new PubSub();
   readonly #pushHandlers: Map<string, (pushMsg: Array<any>) => unknown> = new Map();
-  readonly #builtInSet = new Set<string>;
+  readonly #builtInSet: ReadonlySet<string>;
 
   get isPubSubActive() {
     return this.#pubSub.isActive;
@@ -76,9 +76,11 @@ export default class RedisCommandsQueue {
     this.#pushHandlers.set(COMMANDS[PUBSUB_TYPE.SHARDED].message.toString(), this.#pubSub.handleMessageReplySharded.bind(this.#pubSub));
     this.#pushHandlers.set(COMMANDS[PUBSUB_TYPE.SHARDED].subscribe.toString(), this.#handleStatusReply.bind(this));
     this.#pushHandlers.set(COMMANDS[PUBSUB_TYPE.SHARDED].unsubscribe.toString(), this.#handleShardedUnsubscribe.bind(this));
-
+
+    const s = new Set<string>();
+    this.#builtInSet = s;
     for (const str in this.#pushHandlers.keys) {
-      this.#builtInSet.add(str);
+      s.add(str);
     }
 
     this.decoder = this.#initiateDecoder();
@@ -122,6 +124,14 @@ export default class RedisCommandsQueue {
     this.#pushHandlers.set(messageType, handler);
   }
 
+  removePushHandler(messageType: string) {
+    if (this.#builtInSet.has(messageType)) {
+      throw new Error("Cannot override built in push message handler");
+    }
+
+    this.#pushHandlers.delete(messageType);
+  }
+
   #onPush(push: Array<any>) {
     const handler = this.#pushHandlers.get(push[0].toString());
     if (handler) {
@@ -141,9 +151,7 @@ export default class RedisCommandsQueue {
       onReply: reply => this.#onReply(reply),
       onErrorReply: err => this.#onErrorReply(err),
       onPush: push => {
-        if (!this.#onPush(push)) {
-
-        }
+        return this.#onPush(push);
       },
       getTypeMapping: () => this.#getTypeMapping()
     });

packages/client/lib/client/index.spec.ts

@@ -9,6 +9,7 @@ import { MATH_FUNCTION, loadMathFunction } from '../commands/FUNCTION_LOAD.spec'
 import { RESP_TYPES } from '../RESP/decoder';
 import { BlobStringReply, NumberReply } from '../RESP/types';
 import { SortedSetMember } from '../commands/generic-transformers';
+import { createClient } from '../..';
 
 export const SQUARE_SCRIPT = defineScript({
   SCRIPT:
@@ -769,4 +770,79 @@ describe('Client', () => {
       }
     }, GLOBAL.SERVERS.OPEN);
   });
+
+  describe('Push Handlers', () => {
+    testUtils.testWithClient('RESP2: add/remove invalidate handler, and validate its called', async client => {
+      const key = 'x'
+
+      const duplicate = await client.duplicate().connect();
+      try {
+        const id = await duplicate.clientId();
+
+        let nodeResolve;
+
+        const promise = new Promise((res) => {
+          nodeResolve = res;
+        });
+
+        duplicate.addPushHandler("invalidate", (push: Array<any>) => {
+          assert.equal(push[0].toString(), "invalidate");
+          assert.notEqual(push[1], null);
+          assert.equal(push[1].length, 1);
+          assert.equal(push[1][0].toString(), key);
+          // this test removing the handler,
+          // as flushAll in cleanup of test will issue a full invalidate,
+          // which would fail if this handler is called on it
+          duplicate.removePushHandler("invalidate");
+          nodeResolve();
+        })
+
+        await client.sendCommand(['CLIENT', 'TRACKING', 'ON', 'REDIRECT', id.toString()]);
+        await client.get(key);
+        await client.set(key, '1');
+
+        // force an invalidate all
+        await client.flushAll();
+
+        await nodeResolve;
+      } finally {
+        duplicate.destroy();
+      }
+    }, {
+        ...GLOBAL.SERVERS.OPEN
+    });
+
+    testUtils.testWithClient('RESP3: add/remove invalidate handler, and validate its called', async client => {
+      const key = 'x'
+
+      let nodeResolve;
+
+      const promise = new Promise((res) => {
+        nodeResolve = res;
+      });
+
+      client.addPushHandler("invalidate", (push: Array<any>) => {
+        assert.equal(push[0].toString(), "invalidate");
+        assert.equal(push[1].length, 1);
+        assert.equal(push[1].length, 1);
+        assert.equal(push[1][0].toString(), key);
+        // this test removing the handler,
+        // as flushAll in cleanup of test will issue a full invalidate,
+        // which would fail if this handler is called on it
+        client.removePushHandler("invalidate");
+        nodeResolve();
+      })
+
+      await client.sendCommand(['CLIENT', 'TRACKING', 'ON']);
+      await client.get(key);
+      await client.set(key, '1');
+
+      await nodeResolve;
+    }, {
+        ...GLOBAL.SERVERS.OPEN,
+        clientOptions: {
+          RESP: 3
+        }
+    });
+  });
 });

packages/client/lib/client/index.ts

@@ -573,6 +573,14 @@ export default class RedisClient<
     return this as unknown as RedisClientType<M, F, S, RESP, TYPE_MAPPING>;
   }
 
+  addPushHandler(messageType: string, handler: (pushMsg: Array<any>) => unknown) {
+    this._self.#queue.addPushHandler(messageType, handler);
+  }
+
+  removePushHandler(messageType: string) {
+    this._self.#queue.removePushHandler(messageType);
+  }
+
   sendCommand<T = ReplyUnion>(
     args: Array<RedisArgument>,
     options?: CommandOptions