feat: create node and subscription by content topic

.size-limit.cjs

@@ -1,7 +1,7 @@
 module.exports = [
   {
-    name: "Waku core",
-    path: "packages/core/bundle/index.js",
+    name: "Waku node",
+    path: "packages/sdk/bundle/index.js",
     import: "{ WakuNode }",
   },
   {

packages/core/src/index.ts

@@ -1,4 +1,3 @@
-export { DefaultUserAgent } from "./lib/waku.js";
 export { createEncoder, createDecoder } from "./lib/message/version_0.js";
 export type {
   Encoder,
@@ -7,9 +6,6 @@ export type {
 } from "./lib/message/version_0.js";
 export * as message from "./lib/message/index.js";
 
-export * as waku from "./lib/waku.js";
-export { WakuNode, WakuOptions } from "./lib/waku.js";
-
 export * as waku_filter from "./lib/filter/index.js";
 export { wakuFilter, FilterCodecs } from "./lib/filter/index.js";
 

packages/core/src/lib/wait_for_remote_peer.ts

@@ -8,7 +8,7 @@ const log = new Logger("wait-for-remote-peer");
 /**
  * Wait for a remote peer to be ready given the passed protocols.
  * Must be used after attempting to connect to nodes, using
- * {@link @waku/core!WakuNode.dial} or a bootstrap method with
+ * {@link @waku/sdk!WakuNode.dial} or a bootstrap method with
  * {@link @waku/sdk!createLightNode}.
  *
  * If the passed protocols is a GossipSub protocol, then it resolves only once

packages/interfaces/src/protocols.ts

@@ -62,11 +62,11 @@ export type ProtocolCreateOptions = {
    */
   shardInfo?: Partial<ShardingParams>;
   /**
-   * You can pass options to the `Libp2p` instance used by {@link @waku/core!WakuNode} using the `libp2p` property.
+   * You can pass options to the `Libp2p` instance used by {@link @waku/sdk!WakuNode} using the `libp2p` property.
    * This property is the same type as the one passed to [`Libp2p.create`](https://github.com/libp2p/js-libp2p/blob/master/doc/API.md#create)
    * apart that we made the `modules` property optional and partial,
    * allowing its omission and letting Waku set good defaults.
-   * Notes that some values are overridden by {@link @waku/core!WakuNode} to ensure it implements the Waku protocol.
+   * Notes that some values are overridden by {@link @waku/sdk!WakuNode} to ensure it implements the Waku protocol.
    */
   libp2p?: Partial<CreateLibp2pOptions>;
   /**

packages/sdk/src/content_topic.ts

@@ -0,0 +1,121 @@
+import type { Multiaddr } from "@multiformats/multiaddr";
+import { createDecoder, DecodedMessage, waitForRemotePeer } from "@waku/core";
+import {
+  Callback,
+  IDecoder,
+  IFilterSubscription,
+  LightNode,
+  Protocols
+} from "@waku/interfaces";
+import {
+  contentTopicToPubsubTopic,
+  shardInfoToPubsubTopics
+} from "@waku/utils";
+
+import { createLightNode } from "./create.js";
+
+interface CreateTopicOptions {
+  waku?: LightNode;
+  peer: Multiaddr;
+}
+
+// Given a Waku node, peer Multiaddr, and content topic, creates a decoder and
+// subscription for that content topic.
+async function prepareSubscription(
+  waku: LightNode,
+  contentTopic: string,
+  peer: Multiaddr
+): Promise<{
+  decoder: IDecoder<DecodedMessage>;
+  subscription: IFilterSubscription;
+}> {
+  // Validate that the Waku node matches assumptions
+  if (!waku.filter) {
+    throw new Error("Filter protocol missing from Waku node");
+  }
+  const { shardInfo } = waku.libp2p.components.metadata;
+  if (!shardInfo) {
+    throw new Error("Shard info missing from Waku node.");
+  }
+
+  // Validate content topic and ensure node is configured for its corresponding pubsub topic
+  const pubsubTopics = shardInfoToPubsubTopics(shardInfo);
+  const pubsubTopic = contentTopicToPubsubTopic(contentTopic);
+  if (!pubsubTopics.includes(pubsubTopic))
+    throw new Error(
+      "Content topic does not match any pubsub topic in shard info."
+    );
+
+  await waku.dial(peer);
+  await waitForRemotePeer(waku, [Protocols.Filter]);
+
+  // Create decoder and subscription
+  let decoder = createDecoder(contentTopic, pubsubTopic);
+  if (decoder) decoder = decoder ?? decoder;
+  const subscription = await waku.filter.createSubscription(pubsubTopic);
+
+  return { decoder, subscription };
+}
+
+/**
+ * Creates a subscription and streams all new messages for a content topic.
+ * Will create a light node configured for the content topic with default settings if a node is not provided in `opts`.
+ * Assumes node is using autosharding.
+ * @param contentTopic
+ * @param opts
+ */
+export async function streamContentTopic(
+  contentTopic: string,
+  opts: CreateTopicOptions
+): Promise<[ReadableStream<DecodedMessage>, LightNode]> {
+  opts.waku =
+    opts.waku ??
+    (await createLightNode({
+      shardInfo: { contentTopics: [contentTopic] }
+    }));
+  const { decoder, subscription } = await prepareSubscription(
+    opts.waku,
+    contentTopic,
+    opts.peer
+  );
+
+  // Create a ReadableStream that receives any messages for the content topic
+  const messageStream = new ReadableStream<DecodedMessage>({
+    async start(controller) {
+      await subscription.subscribe(decoder, (message) => {
+        controller.enqueue(message);
+      });
+    },
+    cancel() {
+      return subscription.unsubscribe([contentTopic]);
+    }
+  });
+  return [messageStream, opts.waku];
+}
+
+/**
+ * Subscribes to new messages for a content topic via callback function.
+ * Will create a light node configured for the content topic with default settings if a node is not provided in `opts`.
+ * Assumes node is using autosharding.
+ * @param contentTopic
+ * @param callback Called every time a new message is received on the content topic
+ * @param opts
+ */
+export async function subscribeToContentTopic(
+  contentTopic: string,
+  callback: Callback<DecodedMessage>,
+  opts: CreateTopicOptions
+): Promise<{ subscription: IFilterSubscription; waku: LightNode }> {
+  opts.waku =
+    opts.waku ??
+    (await createLightNode({
+      shardInfo: { contentTopics: [contentTopic] }
+    }));
+  const { decoder, subscription } = await prepareSubscription(
+    opts.waku,
+    contentTopic,
+    opts.peer
+  );
+  await subscription.subscribe(decoder, callback);
+  return { subscription, waku: opts.waku };
+}

packages/sdk/src/create.ts

@@ -6,15 +6,7 @@ import { mplex } from "@libp2p/mplex";
 import { ping } from "@libp2p/ping";
 import { webSockets } from "@libp2p/websockets";
 import { all as filterAll } from "@libp2p/websockets/filters";
-import {
-  DefaultUserAgent,
-  wakuFilter,
-  wakuLightPush,
-  wakuMetadata,
-  WakuNode,
-  WakuOptions,
-  wakuStore
-} from "@waku/core";
+import { wakuFilter, wakuLightPush, wakuMetadata, wakuStore } from "@waku/core";
 import { enrTree, wakuDnsDiscovery } from "@waku/dns-discovery";
 import {
   type CreateLibp2pOptions,
@@ -34,6 +26,8 @@ import { RelayCreateOptions, wakuGossipSub, wakuRelay } from "@waku/relay";
 import { ensureShardingConfigured } from "@waku/utils";
 import { createLibp2p } from "libp2p";
 
+import { DefaultUserAgent, WakuNode, WakuOptions } from "./waku.js";
+
 const DEFAULT_NODE_REQUIREMENTS = {
   lightPush: 1,
   filter: 1,

packages/sdk/src/index.ts

@@ -1,9 +1,4 @@
-export {
-  waitForRemotePeer,
-  createEncoder,
-  createDecoder,
-  WakuNode
-} from "@waku/core";
+export { waitForRemotePeer, createEncoder, createDecoder } from "@waku/core";
 export {
   DecodedMessage,
   Decoder,
@@ -12,6 +7,8 @@ export {
 
 export { utf8ToBytes, bytesToUtf8 } from "@waku/utils/bytes";
 
+export * from "./content_topic.js";
+export * from "./waku.js";
 export * from "./create.js";
 export * as waku from "@waku/core";
 export * as utils from "@waku/utils";

packages/sdk/src/relay/index.ts

@@ -1,4 +1,3 @@
-import { WakuNode, WakuOptions } from "@waku/core";
 import {
   DefaultPubsubTopic,
   type ProtocolCreateOptions,
@@ -8,6 +7,7 @@ import { RelayCreateOptions, wakuGossipSub, wakuRelay } from "@waku/relay";
 import { ensureShardingConfigured } from "@waku/utils";
 
 import { defaultLibp2p, defaultPeerDiscoveries } from "../create.js";
+import { WakuNode, WakuOptions } from "../waku.js";
 
 /**
  * Create a Waku node that uses Waku Relay to send and receive messages,

packages/sdk/src/waku.ts

@@ -1,19 +1,23 @@
 import type { Stream } from "@libp2p/interface";
 import { isPeerId, PeerId } from "@libp2p/interface";
 import { multiaddr, Multiaddr, MultiaddrInput } from "@multiformats/multiaddr";
+import { ConnectionManager, DecodedMessage } from "@waku/core";
 import type {
+  Callback,
   IFilter,
+  IFilterSubscription,
   ILightPush,
   IRelay,
   IStore,
   Libp2p,
+  LightNode,
   PubsubTopic,
   Waku
 } from "@waku/interfaces";
 import { Protocols } from "@waku/interfaces";
 import { Logger } from "@waku/utils";
 
-import { ConnectionManager } from "./connection_manager.js";
+import { subscribeToContentTopic } from "./content_topic.js";
 
 export const DefaultPingKeepAliveValueSecs = 5 * 60;
 export const DefaultRelayKeepAliveValueSecs = 5 * 60;
@@ -180,6 +184,19 @@ export class WakuNode implements Waku {
     await this.libp2p.stop();
   }
 
+  async subscribeToContentTopic(
+    contentTopic: string,
+    peer: Multiaddr,
+    callback: Callback<DecodedMessage>
+  ): Promise<IFilterSubscription> {
+    return (
+      await subscribeToContentTopic(contentTopic, callback, {
+        waku: this as LightNode,
+        peer
+      })
+    ).subscription;
+  }
+
   isStarted(): boolean {
     return this.libp2p.status == "started";
   }

packages/tests/tests/sdk/content_topic.spec.ts

@@ -0,0 +1,175 @@
+import { wakuFilter } from "@waku/core";
+import {
+  bytesToUtf8,
+  createEncoder,
+  createLightNode,
+  DEFAULT_CLUSTER_ID,
+  defaultLibp2p,
+  LightNode,
+  Protocols,
+  streamContentTopic,
+  subscribeToContentTopic,
+  utf8ToBytes,
+  waitForRemotePeer,
+  WakuNode
+} from "@waku/sdk";
+import {
+  contentTopicToPubsubTopic,
+  ensureShardingConfigured,
+  pubsubTopicToSingleShardInfo
+} from "@waku/utils";
+import { expect } from "chai";
+
+import { makeLogFileName, ServiceNode, tearDownNodes } from "../../src";
+
+describe("SDK: Creating by Content Topic", function () {
+  const ContentTopic = "/myapp/1/latest/proto";
+  const testMessage = "Test123";
+  let nwaku: ServiceNode;
+  let waku: LightNode;
+  let waku2: LightNode;
+
+  beforeEach(async function () {
+    this.timeout(15000);
+    nwaku = new ServiceNode(makeLogFileName(this) + "1");
+    await nwaku.start({
+      pubsubTopic: [contentTopicToPubsubTopic(ContentTopic)],
+      lightpush: true,
+      relay: true,
+      filter: true,
+      discv5Discovery: true,
+      peerExchange: true,
+      clusterId: DEFAULT_CLUSTER_ID
+    });
+  });
+
+  afterEach(async function () {
+    this.timeout(15000);
+    await tearDownNodes(nwaku, [waku, waku2]);
+  });
+
+  it("given a content topic, creates a waku node and filter subscription", async function () {
+    const expectedPubsubTopic = contentTopicToPubsubTopic(ContentTopic);
+
+    waku = (
+      await subscribeToContentTopic(ContentTopic, () => {}, {
+        peer: await nwaku.getMultiaddrWithId()
+      })
+    ).waku;
+
+    expect((waku as WakuNode).pubsubTopics).to.include(expectedPubsubTopic);
+  });
+
+  it("given a waku node and content topic, creates a filter subscription", async function () {
+    const expectedPubsubTopic = contentTopicToPubsubTopic(ContentTopic);
+
+    waku = await createLightNode({
+      shardInfo: { contentTopics: [ContentTopic] }
+    });
+    await subscribeToContentTopic(ContentTopic, () => {}, {
+      waku,
+      peer: await nwaku.getMultiaddrWithId()
+    });
+
+    expect((waku as WakuNode).pubsubTopics).to.include(expectedPubsubTopic);
+  });
+
+  it("receives messages sent to provided content topic through callback", async function () {
+    const messages: string[] = [];
+    waku = (
+      await subscribeToContentTopic(
+        ContentTopic,
+        (msg) => {
+          messages.push(bytesToUtf8(msg.payload));
+        },
+        {
+          peer: await nwaku.getMultiaddrWithId()
+        }
+      )
+    ).waku;
+
+    waku2 = await createLightNode({
+      shardInfo: { contentTopics: [ContentTopic] }
+    });
+    await waku2.dial(await nwaku.getMultiaddrWithId());
+    await waitForRemotePeer(waku2, [Protocols.LightPush]);
+    const encoder = createEncoder({
+      pubsubTopicShardInfo: pubsubTopicToSingleShardInfo(
+        contentTopicToPubsubTopic(ContentTopic)
+      ),
+      contentTopic: ContentTopic
+    });
+    await waku2.lightPush?.send(encoder, {
+      payload: utf8ToBytes(testMessage)
+    });
+
+    expect(messages[0]).to.be.eq(testMessage);
+  });
+
+  it("receives messages sent to provided content topic through callback (Waku class)", async function () {
+    const messages: string[] = [];
+    const shardInfo = ensureShardingConfigured({
+      contentTopics: [ContentTopic]
+    });
+    const wakuContentTopic = new WakuNode(
+      {
+        pubsubTopics: shardInfo.pubsubTopics
+      },
+      await defaultLibp2p(shardInfo.shardInfo, undefined, {}, undefined),
+      undefined,
+      undefined,
+      wakuFilter({ pubsubTopics: shardInfo.pubsubTopics })
+    );
+    await wakuContentTopic.subscribeToContentTopic(
+      ContentTopic,
+      await nwaku.getMultiaddrWithId(),
+      (msg) => {
+        messages.push(bytesToUtf8(msg.payload));
+      }
+    );
+
+    waku2 = await createLightNode({
+      shardInfo: { contentTopics: [ContentTopic] }
+    });
+    await waku2.dial(await nwaku.getMultiaddrWithId());
+    await waitForRemotePeer(waku2, [Protocols.LightPush]);
+    const encoder = createEncoder({
+      pubsubTopicShardInfo: pubsubTopicToSingleShardInfo(
+        contentTopicToPubsubTopic(ContentTopic)
+      ),
+      contentTopic: ContentTopic
+    });
+    await waku2.lightPush?.send(encoder, {
+      payload: utf8ToBytes(testMessage)
+    });
+
+    expect(messages[0]).to.be.eq(testMessage);
+  });
+
+  it("receives messages sent to provided content topic through stream", async function () {
+    let stream;
+    [stream, waku] = await streamContentTopic(ContentTopic, {
+      peer: await nwaku.getMultiaddrWithId()
+    });
+
+    waku2 = await createLightNode({
+      shardInfo: { contentTopics: [ContentTopic] }
+    });
+    await waku2.dial(await nwaku.getMultiaddrWithId());
+    await waitForRemotePeer(waku2, [Protocols.LightPush]);
+
+    const encoder = createEncoder({
+      pubsubTopicShardInfo: pubsubTopicToSingleShardInfo(
+        contentTopicToPubsubTopic(ContentTopic)
+      ),
+      contentTopic: ContentTopic
+    });
+    await waku2.lightPush?.send(encoder, {
+      payload: utf8ToBytes(testMessage)
+    });
+
+    const reader = stream.getReader();
+    const { value: message } = await reader.read();
+    expect(bytesToUtf8(message!.payload)).to.be.eq(testMessage);
+  });
+});

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

@@ -1,10 +1,6 @@
 import { bootstrap } from "@libp2p/bootstrap";
 import type { PeerId } from "@libp2p/interface";
-import {
-  DecodedMessage,
-  DefaultUserAgent,
-  waitForRemotePeer
-} from "@waku/core";
+import { DecodedMessage, waitForRemotePeer } from "@waku/core";
 import type { LightNode, RelayNode, Waku } from "@waku/interfaces";
 import { Protocols } from "@waku/interfaces";
 import { generateSymmetricKey } from "@waku/message-encryption";
@@ -14,7 +10,8 @@ import {
 } from "@waku/message-encryption/symmetric";
 import {
   createLightNode,
-  createEncoder as createPlainEncoder
+  createEncoder as createPlainEncoder,
+  DefaultUserAgent
 } from "@waku/sdk";
 import { createRelayNode } from "@waku/sdk/relay";
 import { bytesToUtf8, utf8ToBytes } from "@waku/utils/bytes";