Initial Commit

packages/networking/drive/drive-mesh-protocol/tests/piggyback-presence.test.ts

@@ -0,0 +1,78 @@
+/**
+ * DMP-11 — Response presence piggyback.
+ *
+ * `ChunkResponsePayload` includes `presence` (the responder's full
+ * inventory bitset) and `generation`; receivers update their peer
+ * index from this payload without requiring a separate `cd:advertise`.
+ */
+
+import { describe, expect, it } from "@suaveplan/testing/runner";
+import {
+    chunkIdsToRawBitset,
+    decodeFramedBitset,
+    decodeResponsePayload,
+    encodeFramedBitset,
+    encodeResponsePayload,
+    GenerationTracker,
+    rawBitsetToChunkIds,
+} from "../src/index.js";
+import type { ChunkResponsePayload } from "../src/types/protocol.types.js";
+
+const FILE_ID = "c".repeat(64);
+const PEER = "responder";
+
+describe("DMP-11 — presence piggyback", () => {
+    it("cd:response payload updates peer-index without cd:advertise", {
+        timeout: 5000,
+    }, () => {
+        const inventory = [0, 5, 17, 99];
+        const presence = encodeFramedBitset(
+            chunkIdsToRawBitset(inventory, 100),
+            100
+        );
+        const payload: ChunkResponsePayload = {
+            fileId: FILE_ID,
+            chunks: [
+                { chunkId: 0, bytes: new Uint8Array([0xa1]) },
+                { chunkId: 5, bytes: new Uint8Array([0xa2]) },
+            ],
+            presence,
+            generation: 11,
+        };
+        const wire = encodeResponsePayload(payload);
+        const decoded = decodeResponsePayload(wire);
+        expect(decoded.generation).toBe(11);
+        // Receiver decodes the piggybacked bitset and updates its
+        // peer-index for (responder, FILE_ID) — no cd:advertise needed.
+        const decodedPresence = decodeFramedBitset(decoded.presence);
+        const recoveredInventory = rawBitsetToChunkIds(
+            decodedPresence.raw,
+            decodedPresence.bitLength
+        );
+        expect(recoveredInventory).toEqual(inventory);
+
+        const tracker = new GenerationTracker();
+        const observation = tracker.observe(PEER, FILE_ID, decoded.generation);
+        expect(observation.accept).toBe(true);
+        expect(tracker.peek(PEER, FILE_ID)).toBe(11);
+    });
+
+    it("piggyback applies even on partial responses (chunks.length < requested)", {
+        timeout: 5000,
+    }, () => {
+        const presence = encodeFramedBitset(
+            chunkIdsToRawBitset([3, 7], 16),
+            16
+        );
+        const partial: ChunkResponsePayload = {
+            fileId: FILE_ID,
+            chunks: [{ chunkId: 3, bytes: new Uint8Array([0xc0]) }],
+            presence,
+            generation: 4,
+        };
+        const wire = encodeResponsePayload(partial);
+        const round = decodeResponsePayload(wire);
+        expect(round.chunks.length).toBe(1);
+        expect(round.presence).toEqual(presence);
+    });
+});