Merge pull request #62 from square/jw/trigger-after-commit

Trigger notifications after commit.

Author: Alec Strong

sqlbrite/src/androidTest/java/com/squareup/sqlbrite/BriteDatabaseTest.java

@@ -39,6 +39,7 @@
 import org.junit.runner.RunWith;
 import rx.Observable;
 import rx.Subscription;
+import rx.functions.Action1;
 import rx.functions.Func1;
 import rx.observables.BlockingObservable;
 
@@ -503,6 +504,27 @@ public final class BriteDatabaseTest {
         .isExhausted();
   }
 
+  @Test public void transactionCreatedFromTransactionNotificationWorks() {
+    // Tests the case where a transaction is created in the subscriber to a query which gets
+    // notified as the result of another transaction being committed. With improper ordering, this
+    // can result in creating a new transaction before the old is committed on the underlying DB.
+
+    db.createQuery(TABLE_EMPLOYEE, SELECT_EMPLOYEES)
+        .subscribe(new Action1<Query>() {
+          @Override public void call(Query query) {
+            db.newTransaction().end();
+          }
+        });
+
+    Transaction transaction = db.newTransaction();
+    try {
+      db.insert(TABLE_EMPLOYEE, employee("john", "John Johnson"));
+      transaction.markSuccessful();
+    } finally {
+      transaction.end();
+    }
+  }
+
   @Test public void transactionIsCloseable() throws IOException {
     db.createQuery(TABLE_EMPLOYEE, SELECT_EMPLOYEES).subscribe(o);
     o.assertCursor()

sqlbrite/src/main/java/com/squareup/sqlbrite/BriteDatabase.java

@@ -83,6 +83,10 @@ public final class BriteDatabase implements Closeable {
       transactions.set(newTransaction);
       if (logging) log("TXN END %s", transaction);
       getWriteableDatabase().endTransaction();
+      // Send the triggers after ending the transaction in the DB.
+      if (transaction.commit) {
+        sendTableTrigger(transaction.triggers);
+      }
     }
 
     @Override public void close() {
@@ -517,9 +521,10 @@ private static String conflictString(@ConflictAlgorithm int conflictAlgorithm) {
     }
   }
 
-  private final class SqliteTransaction implements SQLiteTransactionListener {
+  private static final class SqliteTransaction implements SQLiteTransactionListener {
     final SqliteTransaction parent;
     final Set<String> triggers = new LinkedHashSet<>();
+    boolean commit;
 
     SqliteTransaction(SqliteTransaction parent) {
       this.parent = parent;
@@ -529,7 +534,7 @@ private final class SqliteTransaction implements SQLiteTransactionListener {
     }
 
     @Override public void onCommit() {
-      sendTableTrigger(triggers);
+      commit = true;
     }
 
     @Override public void onRollback() {