feat: Waku API's subscribe

Introduced a new `subscribe` function to the Waku API.

packages/interfaces/src/message.ts

@@ -105,6 +105,7 @@ export interface IEncoder {
 export interface IDecoder<T extends IDecodedMessage> {
   contentTopic: string;
   pubsubTopic: PubsubTopic;
+  routingInfo: IRoutingInfo;
   fromWireToProtoObj: (bytes: Uint8Array) => Promise<IProtoMessage | undefined>;
   fromProtoObj: (
     pubsubTopic: string,

packages/interfaces/src/waku.ts

@@ -11,6 +11,7 @@ import type { HealthStatus } from "./health_status.js";
 import type { Libp2p } from "./libp2p.js";
 import type { ILightPush } from "./light_push.js";
 import { IDecodedMessage, IDecoder, IEncoder } from "./message.js";
+import { ContentTopic } from "./misc.js";
 import type { Protocols } from "./protocols.js";
 import type { IRelay } from "./relay.js";
 import type { ShardId } from "./sharding.js";
@@ -27,7 +28,8 @@ export type CreateEncoderParams = CreateDecoderParams & {
 
 export enum WakuEvent {
   Connection = "waku:connection",
-  Health = "waku:health"
+  Health = "waku:health",
+  SubscribeError = "subscribe:error"
 }
 
 export interface IWakuEvents {
@@ -52,9 +54,25 @@ export interface IWakuEvents {
    * });
    */
   [WakuEvent.Health]: CustomEvent<HealthStatus>;
+
+  /**
+   * Emitted when there is an irrecoverable error when subscribing.
+   *
+   * @example
+   * ```typescript
+   * waku.addEventListener(WakuEvent.SubscribeError, (event) => {
+   *   console.log(event.detail);
+   * });
+   */
+  [WakuEvent.SubscribeError]: CustomEvent<string>;
+}
+
+export interface IMessageEmitterEvents {
+  [contentTopic: string]: CustomEvent<Uint8Array>;
 }
 
 export type IWakuEventEmitter = TypedEventEmitter<IWakuEvents>;
+export type IMessageEmitter = TypedEventEmitter<IMessageEmitterEvents>;
 
 export interface IWaku {
   libp2p: Libp2p;
@@ -78,6 +96,20 @@ export interface IWaku {
    */
   events: IWakuEventEmitter;
 
+  /**
+   * Emits messages on their content topic. Messages may be coming from subscriptions
+   * or store queries (TODO). The payload is directly emitted
+   *
+   * @example
+   * ```typescript
+   * waku.messageEmitter.addEventListener("/some/0/content-topic/proto", (event) => {
+   *  const payload: UInt8Array = event.detail
+   *   MyDecoder.decode(payload);
+   * });
+   * ```
+   */
+  messageEmitter: IMessageEmitter;
+
   /**
    * Returns a unique identifier for a node on the network.
    *
@@ -251,6 +283,8 @@ export interface IWaku {
    */
   createEncoder(params: CreateEncoderParams): IEncoder;
 
+  subscribe(contentTopics: ContentTopic[]): void;
+
   /**
    * @returns {boolean} `true` if the node was started and `false` otherwise
    */

packages/message-encryption/src/crypto/utils.ts

@@ -74,3 +74,32 @@ export async function sign(
 export function keccak256(input: Uint8Array): Uint8Array {
   return new Uint8Array(sha3.keccak256.arrayBuffer(input));
 }
+
+/**
+ * Compare two public keys, can be used to verify that a given signature matches
+ * expectations.
+ *
+ * @param publicKeyA - The first public key to compare
+ * @param publicKeyB - The second public key to compare
+ * @returns true if the public keys are the same
+ */
+export function comparePublicKeys(
+  publicKeyA: Uint8Array | undefined,
+  publicKeyB: Uint8Array | undefined
+): boolean {
+  if (!publicKeyA || !publicKeyB) {
+    return false;
+  }
+
+  if (publicKeyA.length !== publicKeyB.length) {
+    return false;
+  }
+
+  for (let i = 0; i < publicKeyA.length; i++) {
+    if (publicKeyA[i] !== publicKeyB[i]) {
+      return false;
+    }
+  }
+
+  return true;
+}

packages/message-encryption/src/index.ts

@@ -1,11 +1,17 @@
 import {
+  comparePublicKeys,
   generatePrivateKey,
   generateSymmetricKey,
   getPublicKey
 } from "./crypto/index.js";
 import { DecodedMessage } from "./decoded_message.js";
 
-export { generatePrivateKey, generateSymmetricKey, getPublicKey };
+export {
+  generatePrivateKey,
+  generateSymmetricKey,
+  getPublicKey,
+  comparePublicKeys
+};
 export type { DecodedMessage };
 
 export * as ecies from "./ecies.js";

packages/message-encryption/src/symmetric.ts

@@ -206,3 +206,105 @@ export function createDecoder(
 ): Decoder {
   return new Decoder(contentTopic, routingInfo, symKey);
 }
+
+/**
+ * Result of decrypting a message with AES symmetric encryption.
+ */
+export interface SymmetricDecryptionResult {
+  /** The decrypted payload */
+  payload: Uint8Array;
+  /** The signature if the message was signed */
+  signature?: Uint8Array;
+  /** The recovered public key if the message was signed */
+  signaturePublicKey?: Uint8Array;
+}
+
+/**
+ * AES symmetric encryption.
+ *
+ *
+ * Follows [26/WAKU2-PAYLOAD](https://rfc.vac.dev/spec/26/) encryption standard.
+ */
+export class SymmetricEncryption {
+  /**
+   * Creates an AES Symmetric encryption instance.
+   *
+   * @param symKey - The symmetric key for encryption (32 bytes recommended)
+   * @param sigPrivKey - Optional private key to sign messages before encryption
+   */
+  public constructor(
+    private symKey: Uint8Array,
+    private sigPrivKey?: Uint8Array
+  ) {}
+
+  /**
+   * Encrypts a byte array payload.
+   *
+   * The encryption process:
+   * 1. Optionally signs the payload with the private key
+   * 2. Adds padding to obscure payload size
+   * 3. Encrypts using AES-256-GCM
+   *
+   * @param payload - The data to encrypt
+   * @returns The encrypted payload
+   */
+  public async encrypt(payload: Uint8Array): Promise<Uint8Array> {
+    const preparedPayload = await preCipher(payload, this.sigPrivKey);
+    return encryptSymmetric(preparedPayload, this.symKey);
+  }
+}
+
+/**
+ * AES symmetric decryption.
+ *
+ * Follows [26/WAKU2-PAYLOAD](https://rfc.vac.dev/spec/26/) encryption standard.
+ */
+export class SymmetricDecryption {
+  /**
+   * Creates an AES Symmetric decryption instance.
+   *
+   * @param symKey - The symmetric key for decryption (must match encryption key)
+   */
+  public constructor(private symKey: Uint8Array) {}
+
+  /**
+   * Decrypts an encrypted byte array payload.
+   *
+   * The decryption process:
+   * 1. Decrypts using AES-256-GCM
+   * 2. Removes padding
+   * 3. Verifies and recovers signature if present
+   *
+   * @param encryptedPayload - The encrypted data (from [[SymmetricEncryption.encrypt]])
+   * @returns Object containing the decrypted payload and signature info, or undefined if decryption fails
+   */
+  public async decrypt(
+    encryptedPayload: Uint8Array
+  ): Promise<SymmetricDecryptionResult | undefined> {
+    try {
+      const decryptedData = await decryptSymmetric(
+        encryptedPayload,
+        this.symKey
+      );
+
+      if (!decryptedData) {
+        return undefined;
+      }
+
+      const result = postCipher(decryptedData);
+
+      if (!result) {
+        return undefined;
+      }
+
+      return {
+        payload: result.payload,
+        signature: result.sig?.signature,
+        signaturePublicKey: result.sig?.publicKey
+      };
+    } catch (error) {
+      log.error("Failed to decrypt payload", error);
+      return undefined;
+    }
+  }
+}

packages/sdk/src/reliable_channel/events.ts

@@ -1,4 +1,4 @@
-import { IDecodedMessage, ProtocolError } from "@waku/interfaces";
+import { ProtocolError } from "@waku/interfaces";
 import type { HistoryEntry, MessageId } from "@waku/sds";
 
 export const ReliableChannelEvent = {
@@ -56,8 +56,7 @@ export interface ReliableChannelEvents {
     possibleAckCount: number;
   }>;
   "message-acknowledged": CustomEvent<MessageId>;
-  // TODO probably T extends IDecodedMessage?
-  "message-received": CustomEvent<IDecodedMessage>;
+  "message-received": CustomEvent<Uint8Array>;
   "irretrievable-message": CustomEvent<HistoryEntry>;
   "sending-message-irrecoverable-error": CustomEvent<{
     messageId: MessageId;

packages/sdk/src/reliable_channel/reliable_channel.ts

@@ -1,7 +1,7 @@
 import { TypedEventEmitter } from "@libp2p/interface";
 import { messageHash } from "@waku/core";
 import {
-  type Callback,
+  type ContentTopic,
   type IDecodedMessage,
   type IDecoder,
   type IEncoder,
@@ -23,6 +23,7 @@ import {
   SyncMessage
 } from "@waku/sds";
 import { Logger } from "@waku/utils";
+import { bytesToHex } from "@waku/utils/bytes";
 
 import {
   QueryOnConnect,
@@ -131,10 +132,7 @@ export class ReliableChannel<
     sendOptions?: ISendOptions
   ) => Promise<LightPushSDKResult>;
 
-  private readonly _subscribe: (
-    decoders: IDecoder<T> | IDecoder<T>[],
-    callback: Callback<T>
-  ) => Promise<boolean>;
+  private readonly _subscribe: (contentTopics: ContentTopic[]) => void;
 
   private readonly _retrieve?: <T extends IDecodedMessage>(
     decoders: IDecoder<T>[],
@@ -156,6 +154,7 @@ export class ReliableChannel<
     public node: IWaku,
     public messageChannel: MessageChannel,
     private encoder: IEncoder,
+    // TODO: remove once _retrieve is aligned
     private decoder: IDecoder<T>,
     options?: ReliableChannelOptions
   ) {
@@ -168,15 +167,7 @@ export class ReliableChannel<
       throw "No protocol available to send messages";
     }
 
-    if (node.filter) {
-      this._subscribe = node.filter.subscribe.bind(node.filter);
-    } else if (node.relay) {
-      // TODO: Why do relay and filter have different interfaces?
-      //  this._subscribe = node.relay.subscribeWithUnsubscribe;
-      throw "Not implemented";
-    } else {
-      throw "No protocol available to receive messages";
-    }
+    this._subscribe = node.subscribe.bind(node);
 
     if (node.store) {
       this._retrieve = node.store.queryGenerator.bind(node.store);
@@ -220,7 +211,7 @@ export class ReliableChannel<
         options?.retrieveFrequencyMs,
         this._retrieve,
         async (msg: T) => {
-          await this.processIncomingMessage(msg);
+          await this.processIncomingMessage(msg.payload);
         }
       );
     }
@@ -280,7 +271,7 @@ export class ReliableChannel<
 
     const autoStart = options?.autoStart ?? true;
     if (autoStart) {
-      await messageChannel.start();
+      messageChannel.start();
     }
 
     return messageChannel;
@@ -324,10 +315,11 @@ export class ReliableChannel<
 
         const messageId = ReliableChannel.getMessageId(messagePayload);
 
-        // TODO: should the encoder give me the message hash?
-        // Encoding now to fail early, used later to get message hash
-        const protoMessage = await this.encoder.toProtoObj(wakuMessage);
-        if (!protoMessage) {
+        const retrievalHint = await computeRetrievalHint(
+          messagePayload,
+          this.encoder
+        );
+        if (!retrievalHint) {
           this.safeSendEvent("sending-message-irrecoverable-error", {
             detail: {
               messageId: messageId,
@@ -336,10 +328,6 @@ export class ReliableChannel<
           });
           return { success: false };
         }
-        const retrievalHint = messageHash(
-          this.encoder.pubsubTopic,
-          protoMessage
-        );
 
         this.safeSendEvent("sending-message", {
           detail: messageId
@@ -381,11 +369,14 @@ export class ReliableChannel<
       });
   }
 
-  private async subscribe(): Promise<boolean> {
+  private subscribe(): void {
     this.assertStarted();
-    return this._subscribe(this.decoder, async (message: T) => {
-      await this.processIncomingMessage(message);
-    });
+    this.node.messageEmitter.addEventListener(
+      this.decoder.contentTopic,
+      (event) => void this.processIncomingMessage(event.detail)
+    );
+
+    this._subscribe([this.decoder.contentTopic]);
   }
 
   /**
@@ -393,14 +384,12 @@ export class ReliableChannel<
    * @param msg
    * @private
    */
-  private async processIncomingMessage<T extends IDecodedMessage>(
-    msg: T
-  ): Promise<void> {
+  private async processIncomingMessage(payload: Uint8Array): Promise<void> {
     // New message arrives, we need to unwrap it first
-    const sdsMessage = SdsMessage.decode(msg.payload);
+    const sdsMessage = SdsMessage.decode(payload);
 
     if (!sdsMessage) {
-      log.error("could not SDS decode message", msg);
+      log.error("could not SDS decode message");
       return;
     }
 
@@ -412,8 +401,14 @@ export class ReliableChannel<
       return;
     }
 
-    const retrievalHint = msg.hash;
-    log.info(`processing message ${sdsMessage.messageId}:${msg.hashStr}`);
+    const retrievalHint = await computeRetrievalHint(payload, this.encoder);
+    if (!retrievalHint) {
+      log.error("could not compute retrieval hint");
+      return;
+    }
+    log.info(
+      `processing message ${sdsMessage.messageId}:${bytesToHex(retrievalHint)}`
+    );
     // SDS Message decoded, let's pass it to the channel so we can learn about
     // missing messages or the status of previous outgoing messages
     this.messageChannel.pushIncomingMessage(sdsMessage, retrievalHint);
@@ -422,25 +417,8 @@ export class ReliableChannel<
 
     if (sdsMessage.content && sdsMessage.content.length > 0) {
       // Now, process the message with callback
-
-      // Overrides msg.payload with unwrapped payload
-      // TODO: can we do better?
-      const { payload: _p, ...allButPayload } = msg;
-      const unwrappedMessage = Object.assign(allButPayload, {
-        payload: sdsMessage.content,
-        hash: msg.hash,
-        hashStr: msg.hashStr,
-        version: msg.version,
-        contentTopic: msg.contentTopic,
-        pubsubTopic: msg.pubsubTopic,
-        timestamp: msg.timestamp,
-        rateLimitProof: msg.rateLimitProof,
-        ephemeral: msg.ephemeral,
-        meta: msg.meta
-      });
-
       this.safeSendEvent("message-received", {
-        detail: unwrappedMessage as unknown as T
+        detail: sdsMessage.content
       });
     }
 
@@ -451,7 +429,7 @@ export class ReliableChannel<
     messages: T[]
   ): Promise<void> {
     for (const message of messages) {
-      await this.processIncomingMessage(message);
+      await this.processIncomingMessage(message.payload);
     }
   }
 
@@ -472,8 +450,8 @@ export class ReliableChannel<
     }
   }
 
-  public async start(): Promise<boolean> {
-    if (this._started) return true;
+  public start(): void {
+    if (this._started) return;
     this._started = true;
     this.setupEventListeners();
     this.restartSync();
@@ -482,7 +460,7 @@ export class ReliableChannel<
       this.missingMessageRetriever?.start();
       this.queryOnConnect?.start();
     }
-    return this.subscribe();
+    this.subscribe();
   }
 
   public stop(): void {
@@ -689,3 +667,16 @@ export class ReliableChannel<
     }
   }
 }
+
+async function computeRetrievalHint(
+  payload: Uint8Array,
+  encoder: IEncoder
+): Promise<Uint8Array | undefined> {
+  // TODO: should the encoder give me the message hash?
+  // Encoding now to fail early, used later to get message hash
+  const protoMessage = await encoder.toProtoObj({ payload });
+  if (!protoMessage) {
+    return undefined;
+  }
+  return messageHash(encoder.pubsubTopic, protoMessage);
+}

packages/sdk/src/waku/waku.ts

@@ -5,8 +5,14 @@ import {
   TypedEventEmitter
 } from "@libp2p/interface";
 import type { MultiaddrInput } from "@multiformats/multiaddr";
-import { ConnectionManager, createDecoder, createEncoder } from "@waku/core";
-import type {
+import {
+  ConnectionManager,
+  createDecoder,
+  createEncoder,
+  DecodedMessage
+} from "@waku/core";
+import {
+  ContentTopic,
   CreateDecoderParams,
   CreateEncoderParams,
   CreateNodeOptions,
@@ -15,20 +21,22 @@ import type {
   IEncoder,
   IFilter,
   ILightPush,
+  IMessageEmitter,
   IRelay,
   IRoutingInfo,
   IStore,
   IWaku,
   IWakuEventEmitter,
   Libp2p,
-  NetworkConfig
+  NetworkConfig,
+  PubsubTopic
 } from "@waku/interfaces";
 import {
   DefaultNetworkConfig,
   HealthStatus,
   Protocols
 } from "@waku/interfaces";
-import { createRoutingInfo, Logger } from "@waku/utils";
+import { createRoutingInfo, Logger, pushOrInitMapSet } from "@waku/utils";
 
 import { Filter } from "../filter/index.js";
 import { HealthIndicator } from "../health_indicator/index.js";
@@ -54,6 +62,7 @@ export class WakuNode implements IWaku {
   public lightPush?: ILightPush;
 
   public readonly events: IWakuEventEmitter = new TypedEventEmitter();
+  public readonly messageEmitter: IMessageEmitter = new TypedEventEmitter();
 
   private readonly networkConfig: NetworkConfig;
 
@@ -134,6 +143,41 @@ export class WakuNode implements IWaku {
     );
   }
 
+  public subscribe(contentTopics: ContentTopic[]): void {
+    // Group decoders by pubsubTopics in case they spread across several shards
+    const ctToDecoders: Map<
+      PubsubTopic,
+      Set<IDecoder<DecodedMessage>>
+    > = new Map();
+    for (const contentTopic of contentTopics) {
+      const decoder = this.createDecoder({ contentTopic });
+      pushOrInitMapSet(ctToDecoders, decoder.pubsubTopic, decoder);
+    }
+
+    if (this.filter) {
+      for (const [_, decoders] of ctToDecoders) {
+        void this.filter
+          .subscribe(
+            Array.from(decoders),
+            this.emitIncomingMessages.bind(this, Array.from(contentTopics))
+          )
+          .then((_) => {
+            // TODO: emit irrecoverable errors
+          })
+          .catch((_) => {
+            // TODO: emit irrecoverable errors
+          });
+      }
+
+      return;
+    }
+
+    if (this.relay) {
+      throw "not implemented";
+    }
+    throw "no subscribe protocol available";
+  }
+
   public get peerId(): PeerId {
     return this.libp2p.peerId;
   }
@@ -288,4 +332,20 @@ export class WakuNode implements IWaku {
   ): IRoutingInfo {
     return createRoutingInfo(this.networkConfig, { contentTopic, shardId });
   }
+
+  private emitIncomingMessages(
+    contentTopics: ContentTopic[],
+    message: {
+      contentTopic: ContentTopic;
+      payload: Uint8Array;
+    }
+  ): void {
+    if (contentTopics.includes(message.contentTopic)) {
+      this.messageEmitter.dispatchEvent(
+        new CustomEvent<Uint8Array>(message.contentTopic, {
+          detail: message.payload
+        })
+      );
+    }
+  }
 }

packages/tests/src/lib/index.ts

@@ -124,14 +124,14 @@ export class ServiceNodesFleet {
 }
 
 class MultipleNodesMessageCollector {
-  public callback: (msg: IDecodedMessage) => void = () => {};
-  protected messageList: Array<IDecodedMessage> = [];
+  public callback: (msg: Partial<IDecodedMessage>) => void = () => {};
+  protected messageList: Array<Partial<IDecodedMessage>> = [];
   public constructor(
     private messageCollectors: MessageCollector[],
     private relayNodes?: ServiceNode[],
     private strictChecking: boolean = false
   ) {
-    this.callback = (msg: IDecodedMessage): void => {
+    this.callback = (msg: Partial<IDecodedMessage>): void => {
       log.info("Got a message");
       this.messageList.push(msg);
     };
@@ -153,7 +153,9 @@ class MultipleNodesMessageCollector {
     }
   }
 
-  public getMessage(index: number): MessageRpcResponse | IDecodedMessage {
+  public getMessage(
+    index: number
+  ): MessageRpcResponse | Partial<IDecodedMessage> {
     return this.messageList[index];
   }
 

packages/tests/tests/waku.node.spec.ts

@@ -7,10 +7,17 @@ import type {
   RelayNode
 } from "@waku/interfaces";
 import { Protocols } from "@waku/interfaces";
-import { generateSymmetricKey } from "@waku/message-encryption";
+import {
+  comparePublicKeys,
+  generatePrivateKey,
+  generateSymmetricKey,
+  getPublicKey
+} from "@waku/message-encryption";
 import {
   createDecoder,
-  createEncoder
+  createEncoder,
+  SymmetricDecryption,
+  SymmetricDecryptionResult
 } from "@waku/message-encryption/symmetric";
 import { createRelayNode } from "@waku/relay";
 import {
@@ -29,8 +36,11 @@ import {
   makeLogFileName,
   NOISE_KEY_1,
   NOISE_KEY_2,
+  runMultipleNodes,
   ServiceNode,
-  tearDownNodes
+  ServiceNodesFleet,
+  tearDownNodes,
+  teardownNodesWithRedundancy
 } from "../src/index.js";
 
 const TestContentTopic = "/test/1/waku/utf8";
@@ -291,3 +301,148 @@ describe("User Agent", function () {
     );
   });
 });
+
+describe("Waku API", function () {
+  describe("WakuNode.subscribe (light node)", function () {
+    this.timeout(100000);
+    let waku: LightNode;
+    let serviceNodes: ServiceNodesFleet;
+    const messageText = "some message";
+    const messagePayload = utf8ToBytes(messageText);
+
+    beforeEachCustom(this, async () => {
+      [serviceNodes, waku] = await runMultipleNodes(
+        this.ctx,
+        TestRoutingInfo,
+        undefined
+      );
+    });
+
+    afterEachCustom(this, async () => {
+      await teardownNodesWithRedundancy(serviceNodes, waku);
+    });
+
+    it("Subscribe and receive messages on 2 different content topics", async function () {
+      // Subscribe to the first content topic and send a message.
+      waku.messageEmitter.addEventListener(TestContentTopic, (event) => {
+        // TODO: fix the callback type
+        serviceNodes.messageCollector.callback({
+          contentTopic: TestContentTopic,
+          payload: event.detail
+        });
+      });
+      waku.subscribe([TestContentTopic]);
+
+      await waku.lightPush.send(TestEncoder, { payload: messagePayload });
+      expect(await serviceNodes.messageCollector.waitForMessages(1)).to.eq(
+        true,
+        "Waiting for the first message"
+      );
+      serviceNodes.messageCollector.verifyReceivedMessage(0, {
+        expectedMessageText: messageText,
+        expectedContentTopic: TestContentTopic,
+        expectedPubsubTopic: TestRoutingInfo.pubsubTopic
+      });
+
+      // Modify subscription to include a new content topic and send a message.
+      const newMessageText = "Filtering still works!";
+      const newContentTopic = "/test/2/waku-filter/default";
+      const newRoutingInfo = createRoutingInfo(DefaultTestNetworkConfig, {
+        contentTopic: newContentTopic
+      });
+      const newEncoder = createPlainEncoder({
+        contentTopic: newContentTopic,
+        routingInfo: newRoutingInfo
+      });
+      // subscribe to second content topic
+      waku.messageEmitter.addEventListener(newContentTopic, (event) => {
+        // TODO: fix the callback type
+        serviceNodes.messageCollector.callback({
+          contentTopic: TestContentTopic,
+          payload: event.detail
+        });
+      });
+      waku.subscribe([newContentTopic]);
+
+      await waku.lightPush.send(newEncoder, {
+        payload: utf8ToBytes(newMessageText)
+      });
+      expect(await serviceNodes.messageCollector.waitForMessages(2)).to.eq(
+        true,
+        "Waiting for the second message"
+      );
+      serviceNodes.messageCollector.verifyReceivedMessage(1, {
+        expectedContentTopic: newContentTopic,
+        expectedMessageText: newMessageText,
+        expectedPubsubTopic: TestRoutingInfo.pubsubTopic
+      });
+
+      // Send another message on the initial content topic to verify it still works.
+      const thirdMessageText = "Filtering still works on first subscription!";
+      const thirdMessagePayload = { payload: utf8ToBytes(thirdMessageText) };
+      await waku.lightPush.send(TestEncoder, thirdMessagePayload);
+      expect(await serviceNodes.messageCollector.waitForMessages(3)).to.eq(
+        true,
+        "Waiting for the third message"
+      );
+      serviceNodes.messageCollector.verifyReceivedMessage(2, {
+        expectedMessageText: thirdMessageText,
+        expectedContentTopic: TestContentTopic,
+        expectedPubsubTopic: TestRoutingInfo.pubsubTopic
+      });
+    });
+
+    it("Subscribe and receive messages encrypted with AES", async function () {
+      const symKey = generateSymmetricKey();
+      const senderPrivKey = generatePrivateKey();
+      // TODO: For now, still using encoder
+      const newEncoder = createEncoder({
+        contentTopic: TestContentTopic,
+        routingInfo: TestRoutingInfo,
+        symKey,
+        sigPrivKey: senderPrivKey
+      });
+
+      // Setup payload decryption
+      const symDecryption = new SymmetricDecryption(symKey);
+
+      // subscribe to second content topic
+      waku.messageEmitter.addEventListener(TestContentTopic, (event) => {
+        const encryptedPayload = event.detail;
+        void symDecryption
+          .decrypt(encryptedPayload)
+          .then((decryptionResult: SymmetricDecryptionResult | undefined) => {
+            if (!decryptionResult) return;
+            serviceNodes.messageCollector.callback({
+              contentTopic: TestContentTopic,
+              payload: decryptionResult.payload
+            });
+
+            // TODO: probably best to adapt the message collector
+            expect(decryptionResult?.signature).to.not.be.undefined;
+            expect(
+              comparePublicKeys(
+                getPublicKey(senderPrivKey),
+                decryptionResult?.signaturePublicKey
+              )
+            );
+            // usually best to ignore decryption failure
+          });
+      });
+      waku.subscribe([TestContentTopic]);
+
+      await waku.lightPush.send(newEncoder, {
+        payload: utf8ToBytes(messageText)
+      });
+      expect(await serviceNodes.messageCollector.waitForMessages(1)).to.eq(
+        true,
+        "Waiting for the message"
+      );
+      serviceNodes.messageCollector.verifyReceivedMessage(1, {
+        expectedContentTopic: TestContentTopic,
+        expectedMessageText: messageText,
+        expectedPubsubTopic: TestRoutingInfo.pubsubTopic
+      });
+    });
+  });
+});