HDFS-13934. Multipart uploaders to be created through FileSystem/FileContext.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/AbstractFileSystem.java

@@ -1383,4 +1383,34 @@ public boolean hasPathCapability(final Path path,
       return false;
     }
   }
+
+  /**
+   * Create a multipart uploader.
+   * @param basePath file path under which all files are uploaded
+   * @return a MultipartUploaderBuilder object to build the uploader
+   * @throws IOException if some early checks cause IO failures.
+   * @throws UnsupportedOperationException if support is checked early.
+   */
+  @InterfaceStability.Unstable
+  public MultipartUploaderBuilder createMultipartUploader(Path basePath)
+      throws IOException {
+    methodNotSupported();
+    return null;
+  }
+
+  /**
+   * Helper method that throws an {@link UnsupportedOperationException} for the
+   * current {@link FileSystem} method being called.
+   */
+  protected final void methodNotSupported() {
+    // The order of the stacktrace elements is (from top to bottom):
+    //   - java.lang.Thread.getStackTrace
+    //   - org.apache.hadoop.fs.FileSystem.methodNotSupported
+    //   - <the FileSystem method>
+    // therefore, to find out the current method name, we use the element at
+    // index 2.
+    String name = Thread.currentThread().getStackTrace()[2].getMethodName();
+    throw new UnsupportedOperationException(getClass().getCanonicalName() +
+        " does not support method " + name);
+  }
 }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/CommonPathCapabilities.java

@@ -131,4 +131,12 @@ private CommonPathCapabilities() {
   @InterfaceStability.Unstable
   public static final String FS_EXPERIMENTAL_BATCH_LISTING =
       "fs.capability.batch.listing";
+
+  /**
+   * Does the store support multipart uploading?
+   * Value: {@value}.
+   */
+  public static final String FS_MULTIPART_UPLOADER =
+      "fs.capability.multipart.uploader";
+
 }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileContext.java

@@ -2957,4 +2957,31 @@ public boolean hasPathCapability(Path path, String capability)
         (fs, p) -> fs.hasPathCapability(p, capability));
   }
 
+  /**
+   * Return a set of server default configuration values based on path.
+   * @param path path to fetch server defaults
+   * @return server default configuration values for path
+   * @throws IOException an I/O error occurred
+   */
+  public FsServerDefaults getServerDefaults(final Path path)
+      throws IOException {
+    return FsLinkResolution.resolve(this,
+        fixRelativePart(path),
+        (fs, p) -> fs.getServerDefaults(p));
+  }
+
+  /**
+   * Create a multipart uploader.
+   * @param basePath file path under which all files are uploaded
+   * @return a MultipartUploaderBuilder object to build the uploader
+   * @throws IOException if some early checks cause IO failures.
+   * @throws UnsupportedOperationException if support is checked early.
+   */
+  @InterfaceStability.Unstable
+  public MultipartUploaderBuilder createMultipartUploader(Path basePath)
+      throws IOException {
+    return FsLinkResolution.resolve(this,
+        fixRelativePart(basePath),
+        (fs, p) -> fs.createMultipartUploader(p));
+  }
 }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileSystem.java

@@ -132,22 +132,35 @@
  * New methods may be marked as Unstable or Evolving for their initial release,
  * as a warning that they are new and may change based on the
  * experience of use in applications.
+ * <p></p>
  * <b>Important note for developers</b>
- *
- * If you're making changes here to the public API or protected methods,
+ * <p></p>
+ * If you are making changes here to the public API or protected methods,
  * you must review the following subclasses and make sure that
  * they are filtering/passing through new methods as appropriate.
+ * <p></p>
  *
- * {@link FilterFileSystem}: methods are passed through.
+ * {@link FilterFileSystem}: methods are passed through. If not,
+ * then {@code TestFilterFileSystem.MustNotImplement} must be
+ * updated with the unsupported interface.
+ * Furthermore, if the new API's support is probed for via
+ * {@link #hasPathCapability(Path, String)} then
+ * {@link FilterFileSystem#hasPathCapability(Path, String)}
+ * must return false, always.
+ * <p></p>
  * {@link ChecksumFileSystem}: checksums are created and
  * verified.
+ * <p></p>
  * {@code TestHarFileSystem} will need its {@code MustNotImplement}
  * interface updated.
+ * <p></p>
  *
  * There are some external places your changes will break things.
  * Do co-ordinate changes here.
+ * <p></p>
  *
  * HBase: HBoss
+ * <p></p>
  * Hive: HiveShim23
  * {@code shims/0.23/src/main/java/org/apache/hadoop/hive/shims/Hadoop23Shims.java}
  *
@@ -4644,4 +4657,17 @@ public CompletableFuture<FSDataInputStream> build() throws IOException {
 
   }
 
+  /**
+   * Create a multipart uploader.
+   * @param basePath file path under which all files are uploaded
+   * @return a MultipartUploaderBuilder object to build the uploader
+   * @throws IOException if some early checks cause IO failures.
+   * @throws UnsupportedOperationException if support is checked early.
+   */
+  @InterfaceStability.Unstable
+  public MultipartUploaderBuilder createMultipartUploader(Path basePath)
+      throws IOException {
+    methodNotSupported();
+    return null;
+  }
 }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FilterFileSystem.java

@@ -41,6 +41,8 @@
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.util.Progressable;
 
+import static org.apache.hadoop.fs.impl.PathCapabilitiesSupport.validatePathCapabilityArgs;
+
 /****************************************************************
  * A <code>FilterFileSystem</code> contains
  * some other file system, which it uses as
@@ -728,7 +730,16 @@ protected CompletableFuture<FSDataInputStream> openFileWithOptions(
   @Override
   public boolean hasPathCapability(final Path path, final String capability)
       throws IOException {
-    return fs.hasPathCapability(path, capability);
+    switch (validatePathCapabilityArgs(makeQualified(path), capability)) {
+    case CommonPathCapabilities.FS_MULTIPART_UPLOADER:
+    case CommonPathCapabilities.FS_EXPERIMENTAL_BATCH_LISTING:
+      // operations known to be unsupported, irrespective of what
+      // the wrapped class implements.
+      return false;
+    default:
+      // the feature is not implemented.
+      return fs.hasPathCapability(path, capability);
+    }
   }
 
 }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FilterFs.java

@@ -448,4 +448,10 @@ public boolean hasPathCapability(final Path path,
       throws IOException {
     return myFs.hasPathCapability(path, capability);
   }
+
+  @Override
+  public MultipartUploaderBuilder createMultipartUploader(final Path basePath)
+      throws IOException {
+    return myFs.createMultipartUploader(basePath);
+  }
 }

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSMultipartUploaderFactory.java → hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/InternalOperations.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -15,26 +15,26 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs;
 
-import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.fs.FileSystem;
-import org.apache.hadoop.fs.FileSystemMultipartUploader;
-import org.apache.hadoop.fs.MultipartUploader;
-import org.apache.hadoop.fs.MultipartUploaderFactory;
-import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.protocol.HdfsConstants;
+package org.apache.hadoop.fs;
+
+import java.io.IOException;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+
 
 /**
- * Support for HDFS multipart uploads, built on
- * {@link FileSystem#concat(Path, Path[])}.
+ *   This method allows access to Package-scoped operations from classes
+ *   in org.apache.hadoop.fs.impl and other file system implementations
+ *   in the hadoop modules.
+ *   This is absolutely not for used by any other application or library.
  */
-public class DFSMultipartUploaderFactory extends MultipartUploaderFactory {
-  protected MultipartUploader createMultipartUploader(FileSystem fs,
-      Configuration conf) {
-    if (fs.getScheme().equals(HdfsConstants.HDFS_URI_SCHEME)) {
-      return new FileSystemMultipartUploader(fs);
-    }
-    return null;
+@InterfaceAudience.Private
+public class InternalOperations {
+
+  @SuppressWarnings("deprecation") // rename w/ OVERWRITE
+  public void rename(FileSystem fs, final Path src, final Path dst,
+      final Options.Rename...options) throws IOException {
+    fs.rename(src, dst, options);
   }
 }