(flink) branch master updated: [FLINK-35756][tests] Make file writing atomically in tests

[snuyanzin]

This is an automated email from the ASF dual-hosted git repository.

snuyanzin pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/flink.git


The following commit(s) were added to refs/heads/master by this push:
     new fd3f1557e7f [FLINK-35756][tests] Make file writing atomically in tests
fd3f1557e7f is described below

commit fd3f1557e7fdf77ecccd0851190a5f746a3b1228
Author: Sergey Nuyanzin <snuyan...@gmail.com>
AuthorDate: Thu Sep 24 08:10:35 2026 +0200

    [FLINK-35756][tests] Make file writing atomically in tests
---
 .../FileSystemTableSourceStreamingITCase.java      | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git 
a/flink-table/flink-table-planner/src/test/java/org/apache/flink/connector/file/table/FileSystemTableSourceStreamingITCase.java
 
b/flink-table/flink-table-planner/src/test/java/org/apache/flink/connector/file/table/FileSystemTableSourceStreamingITCase.java
index d0fef04bfa5..1de397e5760 100644
--- 
a/flink-table/flink-table-planner/src/test/java/org/apache/flink/connector/file/table/FileSystemTableSourceStreamingITCase.java
+++ 
b/flink-table/flink-table-planner/src/test/java/org/apache/flink/connector/file/table/FileSystemTableSourceStreamingITCase.java
@@ -29,8 +29,10 @@ import org.apache.flink.util.CloseableIterator;
 import org.junit.jupiter.api.Test;
 
 import java.io.File;
+import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
 import java.nio.file.StandardOpenOption;
 import java.time.Duration;
 import java.util.ArrayList;
@@ -76,10 +78,7 @@ class FileSystemTableSourceStreamingITCase extends 
StreamingTestBase {
             }
 
             // Write second csv file out
-            Files.write(
-                    Paths.get(testPath.getPath(), "input_1.csv"),
-                    Arrays.asList("4", "5", "6"),
-                    StandardOpenOption.CREATE);
+            writeAtomically(testPath, "input_1.csv", Arrays.asList("4", "5", 
"6"));
 
             // Iterate over the next 3 rows
             for (int i = 0; i < 3; i++) {
@@ -138,10 +137,7 @@ class FileSystemTableSourceStreamingITCase extends 
StreamingTestBase {
             }
 
             // Write second csv file out
-            Files.write(
-                    Paths.get(testPath0.getPath(), "input_1.csv"),
-                    Arrays.asList("7", "8", "9"),
-                    StandardOpenOption.CREATE);
+            writeAtomically(testPath0, "input_1.csv", Arrays.asList("7", "8", 
"9"));
 
             // Iterate over the next 3 rows
             for (int i = 0; i < 3; i++) {
@@ -151,4 +147,14 @@ class FileSystemTableSourceStreamingITCase extends 
StreamingTestBase {
 
         assertThat(actual).containsExactlyInAnyOrder(1, 2, 3, 4, 5, 6, 7, 8, 
9);
     }
+
+    /**
+     * Writes lines into dir/name atomically so the monitor never sees a 
partial file (FLINK-35756).
+     */
+    private static void writeAtomically(File dir, String name, List<String> 
lines)
+            throws IOException {
+        File tmp = File.createTempFile(".tmp", ".tmp", dir);
+        Files.write(tmp.toPath(), lines);
+        Files.move(tmp.toPath(), Paths.get(dir.getPath(), name), 
StandardCopyOption.ATOMIC_MOVE);
+    }
 }