storage: catch errors when loading sync states

automerge · Aug 16, 2024 · c9e8a3b · c9e8a3b
1 parent 9f10cdc
commit c9e8a3b
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Showing 2 changed files with 24 additions and 2 deletions.
diff --git a/packages/automerge-repo/src/storage/StorageSubsystem.ts b/packages/automerge-repo/src/storage/StorageSubsystem.ts
@@ -232,8 +232,13 @@ export class StorageSubsystem {
     storageId: StorageId
   ): Promise<A.SyncState | undefined> {
     const key = [documentId, "sync-state", storageId]
-    const loaded = await this.#storageAdapter.load(key)
-    return loaded ? A.decodeSyncState(loaded) : undefined
+    try {
+      const loaded = await this.#storageAdapter.load(key)
+      return loaded ? A.decodeSyncState(loaded) : undefined
+    } catch (e) {
+      this.#log(`Error loading sync state for ${documentId} from ${storageId}`)
+      return undefined
+    }
   }
 
   async saveSyncState(

diff --git a/packages/automerge-repo/test/StorageSubsystem.test.ts b/packages/automerge-repo/test/StorageSubsystem.test.ts
@@ -211,6 +211,23 @@ describe("StorageSubsystem", () => {
           )
           assert.strictEqual(loadedSyncState, undefined)
         })
+
+        it("returns a undefined if loading an existing sync state fails", async () => {
+          const storage = new StorageSubsystem(adapter)
+
+          const { documentId } = parseAutomergeUrl(generateAutomergeUrl())
+          const bobStorageId = Uuid.v4() as StorageId
+
+          const syncStateKey = [documentId, "sync-state", bobStorageId]
+          // Save garbage data to simulate a corrupted sync state
+          await adapter.save(syncStateKey, Buffer.from("invalid data"))
+
+          const loadedSyncState = await storage.loadSyncState(
+            documentId,
+            bobStorageId
+          )
+          assert.strictEqual(loadedSyncState, undefined)
+        })
       })
 
       describe("storage id", () => {