From e0b4b369dc23e539aa061f97a28f9241263293c0 Mon Sep 17 00:00:00 2001
From: zadam <adam.zivner@gmail.com>
Date: Sun, 14 Jun 2020 00:35:53 +0200
Subject: [PATCH] transaction handling fixes

---
 src/services/backup.js     |  2 +-
 src/services/repository.js |  6 +-----
 src/services/sql.js        | 33 ++++++++++++++++++---------------
 src/services/sync.js       |  2 +-
 4 files changed, 21 insertions(+), 22 deletions(-)

diff --git a/src/services/backup.js b/src/services/backup.js
index 32ae99754..fe0b009ed 100644
--- a/src/services/backup.js
+++ b/src/services/backup.js
@@ -47,7 +47,7 @@ async function copyFile(backupFile) {
 
     for (; attemptCount < COPY_ATTEMPT_COUNT && !success; attemptCount++) {
         try {
-            await sql.executeNoWrap(`VACUUM INTO '${backupFile}'`);
+            await sql.executeWithoutTransaction(`VACUUM INTO '${backupFile}'`);
 
             success = true;
         } catch (e) {
diff --git a/src/services/repository.js b/src/services/repository.js
index 75fba38c5..399f07b5e 100644
--- a/src/services/repository.js
+++ b/src/services/repository.js
@@ -140,10 +140,6 @@ async function updateEntity(entity) {
                 await eventService.emit(entity.isDeleted ? eventService.ENTITY_DELETED : eventService.ENTITY_CHANGED, eventPayload);
             }
         }
-
-        if (entity.afterSaving) {
-            await entity.afterSaving();
-        }
     });
 }
 
@@ -159,4 +155,4 @@ module.exports = {
     getOption,
     updateEntity,
     setEntityConstructor
-};
\ No newline at end of file
+};
diff --git a/src/services/sql.js b/src/services/sql.js
index dc418757d..c5227e685 100644
--- a/src/services/sql.js
+++ b/src/services/sql.js
@@ -155,7 +155,7 @@ async function execute(query, params = []) {
     return await wrap(async db => db.run(query, ...params), query);
 }
 
-async function executeNoWrap(query, params = []) {
+async function executeWithoutTransaction(query, params = []) {
     await dbConnection.run(query, ...params);
 }
 
@@ -222,10 +222,12 @@ async function startTransactionIfNecessary() {
         await transactionPromise;
     }
 
-    await beginTransaction();
-    cls.namespace.set('isInTransaction', true);
+    // first set semaphore (atomic operation and only then start transaction
     transactionActive = true;
     transactionPromise = new Promise(res => transactionPromiseResolve = res);
+    cls.namespace.set('isInTransaction', true);
+
+    await beginTransaction();
 }
 
 async function transactional(func) {
@@ -234,7 +236,7 @@ async function transactional(func) {
         return await func();
     }
 
-    cls.namespace.set('isTransactional', true); // we will need a transaction if there's a write operation
+    cls.namespace.set('isTransactional', true); // this signals that transaction will be needed if there's a write operation
 
     try {
         const ret = await func();
@@ -244,26 +246,27 @@ async function transactional(func) {
 
             // note that sync rows sent from this action will be sent again by scheduled periodic ping
             require('./ws.js').sendPingToAllClients();
-
-            transactionActive = false;
-            cls.namespace.set('isInTransaction', false);
-            transactionPromiseResolve();
         }
 
         return ret;
     }
     catch (e) {
-        if (transactionActive) {
+        if (cls.namespace.get('isInTransaction')) {
             await rollback();
-
-            transactionActive = false;
-            cls.namespace.set('isInTransaction', false);
-            // resolving since this is just semaphore for allowing another write transaction to proceed
-            transactionPromiseResolve();
         }
 
         throw e;
     }
+    finally {
+        cls.namespace.set('isTransactional', false);
+
+        if (cls.namespace.get('isInTransaction')) {
+            transactionActive = false;
+            cls.namespace.set('isInTransaction', false);
+            // resolving even for rollback since this is just semaphore for allowing another write transaction to proceed
+            transactionPromiseResolve();
+        }
+    }
 }
 
 module.exports = {
@@ -278,7 +281,7 @@ module.exports = {
     getMap,
     getColumn,
     execute,
-    executeNoWrap,
+    executeWithoutTransaction,
     executeMany,
     executeScript,
     transactional,
diff --git a/src/services/sync.js b/src/services/sync.js
index acc2ccd90..8d1425637 100644
--- a/src/services/sync.js
+++ b/src/services/sync.js
@@ -372,7 +372,7 @@ sqlInit.dbReady.then(async () => {
     setInterval(cls.wrap(sync), 60000);
 
     // kickoff initial sync immediately
-    setTimeout(cls.wrap(sync), 1000);
+    setTimeout(cls.wrap(sync), 3000);
 
     setInterval(cls.wrap(updatePushStats), 1000);
 });