Use a stream based approach to walk directories
This approach allows solutions to be developed which operate on events
without waiting for the entire listings to be complete.
Change-Id: Ic6e07210d4e319781e70c5f692cfea9c64315f3b
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/ReplicationTasksStorage.java b/src/main/java/com/googlesource/gerrit/plugins/replication/ReplicationTasksStorage.java
index cf34073..fe5e7cb 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/ReplicationTasksStorage.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/ReplicationTasksStorage.java
@@ -24,15 +24,15 @@
import com.google.inject.ProvisionException;
import com.google.inject.Singleton;
import java.io.IOException;
-import java.nio.file.DirectoryIteratorException;
-import java.nio.file.DirectoryStream;
import java.nio.file.Files;
import java.nio.file.NoSuchFileException;
+import java.nio.file.NotDirectoryException;
import java.nio.file.Path;
import java.nio.file.StandardCopyOption;
-import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.transport.URIish;
@@ -71,7 +71,7 @@
} catch (NoSuchFileException e) {
logger.atFine().log("File %s not found while reading task", file);
} catch (IOException e) {
- if (!e.getMessage().equals("Is a directory")) {
+ if (!e.getMessage().contains("not a regular file")) {
logger.atSevere().withCause(e).log("Error while reading task %s", file);
}
}
@@ -161,26 +161,26 @@
return list(createDir(runningUpdates));
}
- private List<ReplicateRefUpdate> list(Path tasks) {
- List<ReplicateRefUpdate> results = new ArrayList<>();
- try (DirectoryStream<Path> events = Files.newDirectoryStream(tasks)) {
- for (Path path : events) {
- Optional<ReplicateRefUpdate> update = ReplicateRefUpdate.createOptionally(path);
- if (update.isPresent()) {
- results.add(update.get());
- } else if (Files.isDirectory(path)) {
- try {
- results.addAll(list(path));
- } catch (DirectoryIteratorException d) {
- // iterating over the sub-directories is expected to have dirs disappear
- Nfs.throwIfNotStaleFileHandle(d.getCause());
- }
- }
- }
- } catch (IOException e) {
- logger.atSevere().withCause(e).log("Error while listing tasks");
+ private List<ReplicateRefUpdate> list(Path taskDir) {
+ return streamRecursive(taskDir).collect(Collectors.toList());
+ }
+
+ private Stream<ReplicateRefUpdate> streamRecursive(Path dir) {
+ return walk(dir)
+ .map(path -> ReplicateRefUpdate.createOptionally(path))
+ .filter(Optional::isPresent)
+ .map(Optional::get);
+ }
+
+ private static Stream<Path> walk(Path path) {
+ try {
+ return Stream.concat(Stream.of(path), Files.list(path).flatMap(sub -> walk(sub)));
+ } catch (NotDirectoryException e) {
+ return Stream.of(path);
+ } catch (Exception e) {
+ logger.atSevere().withCause(e).log("Error while walking directory %s", path);
+ return Stream.empty();
}
- return results;
}
@SuppressWarnings("deprecation")
