workaround missing waitForFirstSync()

nurturenature · Jul 28, 2024 · 9af235c · 9af235c
1 parent 1e97081
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diff --git a/doc/logbook.md b/doc/logbook.md
@@ -4,14 +4,30 @@
 
 Add partitioning and process kill nemeses to flush out more errors and observe behaviors.
 
+
+Workaround `waitForFirstSync()` by sleeping for 1s
+- slightly changes behavior of kill nemesis
+  - minimum of 1s interval between kills vs a possibly, random, interval of 0
+- slightly changes startup behavior
+  - 1s delay avoids the sometimes, random, initial transactions before/during setup
+
+
+Possible Issues
+- frequent, extraneous?, duplicate `SyncStatus` stream messages
+  ```log
+  [2:13:41.301] [powersync_endpoint] FINEST: statusStream: SyncStatus<connected: true connecting: false downloading: true uploading: false lastSyncedAt: 2024-07-28 02:13:40.138093, hasSynced: true, error: null>
+  [2:13:41.301] [powersync_endpoint] FINEST: statusStream: SyncStatus<connected: true connecting: false downloading: true uploading: false lastSyncedAt: 2024-07-28 02:13:40.138093, hasSynced: true, error: null>
+  ```
+
 ---
 
 ### Known Errors In New CrudTransactionConnector 
 
 - PostgreSQL could not serialize access due to concurrent update
   - Max retries, 10, exceeded
 
-TODO: Implement exponential backoff?
+TODO: Implement a try hard, try harder, 'reverse' exponential backoff?
+- fair and polite
 
 ----
 

diff --git a/jepsen/src/powersync/powersync.clj b/jepsen/src/powersync/powersync.clj
@@ -4,7 +4,8 @@
              [db :as db]
              [control :as c]]
             [jepsen.control
-             [util :as cu]]))
+             [util :as cu]]
+            [jepsen.util :as util]))
 
 (def install-dir
   "Directory to install into."
@@ -92,6 +93,9 @@
              :logfile log-file
              :pidfile pid-file}
             bin-path))
+          ; TODO: not possible to waitForFirstSync() in powersync_endpoint, so sleep here
+          (info "Sleeping for 1 second to mimic waitForFirstSync()")
+          (util/sleep 1000)
           :started)))
 
     (kill!

diff --git a/powersync_endpoint/lib/db.dart b/powersync_endpoint/lib/db.dart
@@ -52,8 +52,11 @@ Future<void> initDb() async {
   await db.connect(connector: connector);
   log.info('db connected, connector: $connector, status: ${db.currentStatus}');
 
-  await db.waitForFirstSync();
-  log.info('db first sync completed, status: ${db.currentStatus}');
+  // TODO: disappeared from API?
+  // https://github.com/powersync-ja/powersync.dart/issues/131
+  log.warning("not waitForFirstSync()'ing");
+  // await db.waitForFirstSync();
+  // log.info('db first sync completed, status: ${db.currentStatus}');
 
   // log PowerSync status changes
   // monitor for upload error messages, check if they're ignorable