Merge pull request #1585 from waku-org/fix/light-error-1553

packages/core/src/lib/light_push/index.ts

@@ -1,3 +1,4 @@
+import type { Stream } from "@libp2p/interface/connection";
 import type { PeerId } from "@libp2p/interface/peer-id";
 import {
   IEncoder,
@@ -102,43 +103,63 @@ class LightPush extends BaseProtocol implements ILightPush {
       numPeers: this.NUM_PEERS_PROTOCOL
     });
 
-    const promises = peers.map(async (peer) => {
-      let error: SendError | undefined;
-      const stream = await this.getStream(peer);
+    if (!peers.length) {
+      return {
+        recipients,
+        errors: [SendError.NO_PEER_AVAILABLE]
+      };
+    }
 
+    const promises = peers.map(async (peer) => {
+      let stream: Stream | undefined;
       try {
-        const res = await pipe(
+        stream = await this.getStream(peer);
+      } catch (err) {
+        log(`Failed to get a stream for remote peer${peer.id.toString()}`, err);
+        return { recipients, error: SendError.REMOTE_PEER_FAULT };
+      }
+
+      let res: Uint8ArrayList[] | undefined;
+      try {
+        res = await pipe(
           [query.encode()],
           lp.encode,
           stream,
           lp.decode,
           async (source) => await all(source)
         );
-        try {
+      } catch (err) {
+        log("Failed to send waku light push request", err);
+        return { recipients, error: SendError.GENERIC_FAIL };
+      }
+
       const bytes = new Uint8ArrayList();
       res.forEach((chunk) => {
         bytes.append(chunk);
       });
 
-          const response = PushRpc.decode(bytes).response;
-
-          if (response?.isSuccess) {
-            recipients.some((recipient) => recipient.equals(peer.id)) ||
-              recipients.push(peer.id);
-          } else {
-            log("No response in PushRPC");
-            error = SendError.NO_RPC_RESPONSE;
-          }
+      let response: PushResponse | undefined;
+      try {
+        response = PushRpc.decode(bytes).response;
       } catch (err) {
         log("Failed to decode push reply", err);
-          error = SendError.DECODE_FAILED;
-        }
-      } catch (err) {
-        log("Failed to send waku light push request", err);
-        error = SendError.GENERIC_FAIL;
+        return { recipients, error: SendError.DECODE_FAILED };
       }
 
-      return { recipients, error };
+      if (!response) {
+        log("Remote peer fault: No response in PushRPC");
+        return { recipients, error: SendError.REMOTE_PEER_FAULT };
+      }
+
+      if (!response.isSuccess) {
+        log("Remote peer rejected the message: ", response.info);
+        return { recipients, error: SendError.REMOTE_PEER_REJECTED };
+      }
+
+      recipients.some((recipient) => recipient.equals(peer.id)) ||
+        recipients.push(peer.id);
+
+      return { recipients };
     });
 
     const results = await Promise.allSettled(promises);

packages/interfaces/src/protocols.ts

@@ -59,11 +59,36 @@ export type Callback<T extends IDecodedMessage> = (
 ) => void | Promise<void>;
 
 export enum SendError {
+  /** Could not determine the origin of the fault. Best to check connectivity and try again */
   GENERIC_FAIL = "Generic error",
+  /** Failure to protobuf encode the message. This is not recoverable and needs
+   * further investigation. */
   ENCODE_FAILED = "Failed to encode",
+  /** Failure to protobuf decode the message. May be due to a remote peer issue,
+   * ensuring that messages are sent via several peer enable mitigation of this error.. */
   DECODE_FAILED = "Failed to decode",
+  /** The message size is above the maximum message size allowed on the Waku Network.
+   * Compressing the message or using an alternative strategy for large messages is recommended.
+   */
   SIZE_TOO_BIG = "Size is too big",
-  NO_RPC_RESPONSE = "No RPC response"
+  /**
+   * Failure to find a peer with suitable protocols. This may due to a connection issue.
+   * Mitigation can be: retrying after a given time period, display connectivity issue
+   * to user or listening for `peer:connected:bootstrap` or `peer:connected:peer-exchange`
+   * on the connection manager before retrying.
+   */
+  NO_PEER_AVAILABLE = "No peer available",
+  /**
+   * The remote peer did not behave as expected. Mitigation for `NO_PEER_AVAILABLE`
+   * or `DECODE_FAILED` can be used.
+   */
+  REMOTE_PEER_FAULT = "Remote peer fault",
+  /**
+   * The remote peer rejected the message. Information provided by the remote peer
+   * is logged. Review message validity, or mitigation for `NO_PEER_AVAILABLE`
+   * or `DECODE_FAILED` can be used.
+   */
+  REMOTE_PEER_REJECTED = "Remote peer rejected"
 }
 
 export interface SendResult {

packages/tests/tests/light-push/index.spec.ts

@@ -86,7 +86,8 @@ describe("Waku Light Push [node only]", function () {
       });
     } else {
       expect(pushResponse.recipients.length).to.eq(0);
-      expect(pushResponse.errors).to.include(SendError.NO_RPC_RESPONSE);
+      // This should be `REMOTE_PEER_REJECTED`, tracked with https://github.com/waku-org/nwaku/issues/1641
+      expect(pushResponse.errors).to.include(SendError.REMOTE_PEER_FAULT);
       expect(await messageCollector.waitForMessages(1)).to.eq(false);
     }
   });
@@ -158,7 +159,8 @@ describe("Waku Light Push [node only]", function () {
       });
     } else {
       expect(pushResponse.recipients.length).to.eq(0);
-      expect(pushResponse.errors).to.include(SendError.NO_RPC_RESPONSE);
+      // Should be `REMOTE_PEER_REJECTED`, tracked with https://github.com/waku-org/nwaku/issues/2059
+      expect(pushResponse.errors).to.include(SendError.REMOTE_PEER_FAULT);
       expect(await messageCollector.waitForMessages(1)).to.eq(false);
     }
   });