Add some initial utilities for copying files.

Author: brendandburns

examples/src/main/java/io/kubernetes/client/examples/CopyExample.java

@@ -0,0 +1,46 @@
+/*
+Copyright 2017, 2018 The Kubernetes Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package io.kubernetes.client.examples;
+
+import com.google.common.io.ByteStreams;
+import io.kubernetes.client.ApiClient;
+import io.kubernetes.client.ApiException;
+import io.kubernetes.client.Configuration;
+import io.kubernetes.client.Copy;
+import io.kubernetes.client.util.Config;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * A simple example of how to use the Java API
+ *
+ * <p>Easiest way to run this: mvn exec:java
+ * -Dexec.mainClass="io.kubernetes.client.examples.CopyExample"
+ *
+ * <p>From inside $REPO_DIR/examples
+ */
+public class CopyExample {
+  public static void main(String[] args) throws IOException, ApiException, InterruptedException {
+    String podName = "kube-addon-manager-minikube";
+    String namespace = "kube-system";
+
+    ApiClient client = Config.defaultClient();
+    Configuration.setDefaultApiClient(client);
+
+    Copy copy = new Copy();
+    InputStream dataStream = copy.copyFile(namespace, podName, "/etc/motd");
+
+    ByteStreams.copy(dataStream, System.out);
+  }
+}

util/src/main/java/io/kubernetes/client/Copy.java

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+/*
+Copyright 2017, 2018 The Kubernetes Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package io.kubernetes.client;
+
+import com.google.common.io.ByteStreams;
+import io.kubernetes.client.models.V1Pod;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Path;
+import org.apache.commons.codec.binary.Base64;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class Copy extends Exec {
+  private static final Logger log = LoggerFactory.getLogger(Copy.class);
+
+  /** Simple Copy constructor, uses default configuration */
+  public Copy() {
+    super(Configuration.getDefaultApiClient());
+  }
+
+  /**
+   * Copy Constructor
+   *
+   * @param apiClient The api client to use.
+   */
+  public Copy(ApiClient apiClient) {
+    super(apiClient);
+  }
+
+  public InputStream copyFile(String namespace, String pod, String srcPath)
+      throws ApiException, IOException {
+    return copyFile(namespace, pod, null, srcPath);
+  }
+
+  public InputStream copyFile(V1Pod pod, String srcPath) throws ApiException, IOException {
+    return copyFile(pod, null, srcPath);
+  }
+
+  public InputStream copyFile(V1Pod pod, String container, String srcPath)
+      throws ApiException, IOException {
+    return copyFile(
+        pod.getMetadata().getNamespace(), pod.getMetadata().getName(), container, srcPath);
+  }
+
+  public InputStream copyFile(String namespace, String pod, String container, String srcPath)
+      throws ApiException, IOException {
+    Process proc =
+        this.exec(
+            namespace,
+            pod,
+            new String[] {"sh", "-c", "cat " + srcPath + " | base64"},
+            container,
+            false,
+            false);
+    try {
+      proc.waitFor();
+    } catch (InterruptedException ex) {
+      log.warn("Interrupted waiting for copy to complete", ex);
+    }
+    ByteArrayOutputStream bos = new ByteArrayOutputStream();
+    ByteStreams.copy(proc.getInputStream(), bos);
+
+    return new ByteArrayInputStream(Base64.decodeBase64(bos.toByteArray()));
+  }
+
+  public static void copyFile(String namespace, String pod, String srcPath, Path dest)
+      throws ApiException, IOException {
+    Copy c = new Copy();
+    InputStream is = c.copyFile(namespace, pod, null, srcPath);
+    FileOutputStream os = new FileOutputStream(dest.toFile());
+    ByteStreams.copy(is, os);
+    os.flush();
+    os.close();
+  }
+}