Add functional methods for snapshots and Snapshot class

gcloud-java-compute/src/main/java/com/google/gcloud/compute/Compute.java

@@ -821,6 +821,54 @@ public static AddressFilter notEquals(AddressField field, String value) {
     }
   }
 
+  /**
+   * Class for filtering snapshot lists.
+   */
+  class SnapshotFilter extends ListFilter {
+
+    private static final long serialVersionUID = 8757711630092406747L;
+
+    SnapshotFilter(SnapshotField field, ComparisonOperator operator, Object value) {
+      super(field.selector(), operator, value);
+    }
+
+    /**
+     * Returns an equality filter for the given field and string value. For string fields,
+     * {@code value} is interpreted as a regular expression using RE2 syntax. {@code value} must
+     * match the entire field.
+     *
+     * @see <a href="https://github.com/google/re2/wiki/Syntax">RE2</a>
+     */
+    public static SnapshotFilter equals(SnapshotField field, String value) {
+      return new SnapshotFilter(checkNotNull(field), ComparisonOperator.EQ, checkNotNull(value));
+    }
+
+    /**
+     * Returns a not-equals filter for the given field and string value. For string fields,
+     * {@code value} is interpreted as a regular expression using RE2 syntax. {@code value} must
+     * match the entire field.
+     *
+     * @see <a href="https://github.com/google/re2/wiki/Syntax">RE2</a>
+     */
+    public static SnapshotFilter notEquals(SnapshotField field, String value) {
+      return new SnapshotFilter(checkNotNull(field), ComparisonOperator.NE, checkNotNull(value));
+    }
+
+    /**
+     * Returns an equality filter for the given field and long value.
+     */
+    public static SnapshotFilter equals(SnapshotField field, long value) {
+      return new SnapshotFilter(checkNotNull(field), ComparisonOperator.EQ, value);
+    }
+
+    /**
+     * Returns a not-equals filter for the given field and long value.
+     */
+    public static SnapshotFilter notEquals(SnapshotField field, long value) {
+      return new SnapshotFilter(checkNotNull(field), ComparisonOperator.NE, value);
+    }
+  }
+
   /**
    * Class for specifying disk type get options.
    */
@@ -1344,6 +1392,73 @@ public static AddressAggregatedListOption pageToken(String pageToken) {
     }
   }
 
+  /**
+   * Class for specifying snapshot get options.
+   */
+  class SnapshotOption extends Option {
+
+    private static final long serialVersionUID = -3505179459035500945L;
+
+    private SnapshotOption(ComputeRpc.Option option, Object value) {
+      super(option, value);
+    }
+
+    /**
+     * Returns an option to specify the snapshot's fields to be returned by the RPC call. If this
+     * option is not provided, all snapshot's fields are returned. {@code SnapshotOption.fields} can
+     * be used to specify only the fields of interest. {@link Snapshot#snapshotId()} is always
+     * returned, even if not specified.
+     */
+    public static SnapshotOption fields(SnapshotField... fields) {
+      return new SnapshotOption(ComputeRpc.Option.FIELDS, SnapshotField.selector(fields));
+    }
+  }
+
+  /**
+   * Class for specifying snapshot list options.
+   */
+  class SnapshotListOption extends Option {
+
+    private static final long serialVersionUID = 8278588147660831257L;
+
+    private SnapshotListOption(ComputeRpc.Option option, Object value) {
+      super(option, value);
+    }
+
+    /**
+     * Returns an option to specify a filter on the snapshots being listed.
+     */
+    public static SnapshotListOption filter(SnapshotFilter filter) {
+      return new SnapshotListOption(ComputeRpc.Option.FILTER, filter.toPb());
+    }
+
+    /**
+     * Returns an option to specify the maximum number of snapshots returned per page.
+     */
+    public static SnapshotListOption pageSize(long pageSize) {
+      return new SnapshotListOption(ComputeRpc.Option.MAX_RESULTS, pageSize);
+    }
+
+    /**
+     * Returns an option to specify the page token from which to start listing snapshots.
+     */
+    public static SnapshotListOption pageToken(String pageToken) {
+      return new SnapshotListOption(ComputeRpc.Option.PAGE_TOKEN, pageToken);
+    }
+
+    /**
+     * Returns an option to specify the snapshot's fields to be returned by the RPC call. If this
+     * option is not provided, all snapshot's fields are returned. {@code SnapshotListOption.fields}
+     * can be used to specify only the fields of interest. {@link Snapshot#snapshotId()} is always
+     * returned, even if not specified.
+     */
+    public static SnapshotListOption fields(SnapshotField... fields) {
+      StringBuilder builder = new StringBuilder();
+      builder.append("items(").append(SnapshotField.selector(fields)).append("),nextPageToken");
+      return new SnapshotListOption(ComputeRpc.Option.FIELDS, builder.toString());
+    }
+  }
+
   /**
    * Returns the requested disk type or {@code null} if not found.
    *
@@ -1525,4 +1640,53 @@ public static AddressAggregatedListOption pageToken(String pageToken) {
    * @throws ComputeException upon failure
    */
   Operation delete(AddressId addressId, OperationOption... options);
+
+  /**
+   * Creates a new snapshot.
+   *
+   * @return a zone operation if the create request was issued correctly, {@code null} if
+   *     {@code snapshot.sourceDisk} was not found
+   * @throws ComputeException upon failure
+   */
+  Operation create(SnapshotInfo snapshot, OperationOption... options);
+
+  /**
+   * Returns the requested snapshot or {@code null} if not found.
+   *
+   * @throws ComputeException upon failure
+   */
+  Snapshot getSnapshot(String snapshot, SnapshotOption... options);
+
+  /**
+   * Lists all snapshots.
+   *
+   * @throws ComputeException upon failure
+   */
+  Page<Snapshot> listSnapshots(SnapshotListOption... options);
+
+  /**
+   * Deletes the requested snapshot. Keep in mind that deleting a single snapshot might not
+   * necessarily delete all the data for that snapshot. If any data for the snapshot that is marked
+   * for deletion is needed for subsequent snapshots, the data will be moved to the next snapshot.
+   *
+   * @return a global operation if the request was issued correctly, {@code null} if the snapshot
+   *     was not found
+   * @throws ComputeException upon failure
+   * @see <a href="https://cloud.google.com/compute/docs/disks/persistent-disks#deleting_snapshot>
+   *     Deleting a snapshot</a>
+   */
+  Operation deleteSnapshot(SnapshotId snapshot, OperationOption... options);
+
+  /**
+   * Deletes the requested snapshot. Keep in mind that deleting a single snapshot might not
+   * necessarily delete all the data for that snapshot. If any data on the snapshot that is marked
+   * for deletion is needed for subsequent snapshots, the data will be moved to the next snapshot.
+   *
+   * @return a global operation if the request was issued correctly, {@code null} if the snapshot
+   *     was not found
+   * @throws ComputeException upon failure
+   * @see <a href="https://cloud.google.com/compute/docs/disks/persistent-disks#deleting_snapshot>
+   *     Deleting a snapshot</a>
+   */
+  Operation deleteSnapshot(String snapshot, OperationOption... options);
 }

gcloud-java-compute/src/main/java/com/google/gcloud/compute/ComputeImpl.java

@@ -273,6 +273,25 @@ public Page<Address> nextPage() {
     }
   }
 
+  private static class SnapshotPageFetcher implements NextPageFetcher<Snapshot> {
+
+    private static final long serialVersionUID = 6205774609802216986L;
+    private final Map<ComputeRpc.Option, ?> requestOptions;
+    private final ComputeOptions serviceOptions;
+
+    SnapshotPageFetcher(ComputeOptions serviceOptions, String cursor,
+        Map<ComputeRpc.Option, ?> optionMap) {
+      this.requestOptions =
+          PageImpl.nextRequestOptions(ComputeRpc.Option.PAGE_TOKEN, cursor, optionMap);
+      this.serviceOptions = serviceOptions;
+    }
+
+    @Override
+    public Page<Snapshot> nextPage() {
+      return listSnapshots(serviceOptions, requestOptions);
+    }
+  }
+
   private final ComputeRpc computeRpc;
 
   ComputeImpl(ComputeOptions options) {
@@ -881,8 +900,8 @@ public Address apply(com.google.api.services.compute.model.Address address) {
               return Address.fromPb(serviceOptions.service(), address);
             }
           });
-      return new PageImpl<>(new AggregatedAddressPageFetcher(serviceOptions, cursor,
-          optionsMap), cursor, operations);
+      return new PageImpl<>(new AggregatedAddressPageFetcher(serviceOptions, cursor, optionsMap),
+          cursor, operations);
     } catch (RetryHelper.RetryHelperException e) {
       throw ComputeException.translateAndThrow(e);
     }
@@ -914,6 +933,99 @@ public com.google.api.services.compute.model.Operation call() {
     }
   }
 
+  @Override
+  public Operation create(SnapshotInfo snapshot, final OperationOption... options) {
+    final SnapshotInfo completeSnapshot = snapshot.setProjectId(options().projectId());
+    final Map<ComputeRpc.Option, ?> optionsMap = optionMap(options);
+    try {
+      com.google.api.services.compute.model.Operation answer =
+          runWithRetries(new Callable<com.google.api.services.compute.model.Operation>() {
+            @Override
+            public com.google.api.services.compute.model.Operation call() {
+              return computeRpc.createSnapshot(completeSnapshot.sourceDisk().zone(),
+                  completeSnapshot.sourceDisk().disk(), completeSnapshot.snapshotId().snapshot(),
+                  completeSnapshot.description(), optionsMap);
+            }
+          }, options().retryParams(), EXCEPTION_HANDLER);
+      return answer == null ? null : Operation.fromPb(this, answer);
+    } catch (RetryHelper.RetryHelperException e) {
+      throw ComputeException.translateAndThrow(e);
+    }
+  }
+
+  @Override
+  public Snapshot getSnapshot(final String snapshot, SnapshotOption... options) {
+    final Map<ComputeRpc.Option, ?> optionsMap = optionMap(options);
+    try {
+      com.google.api.services.compute.model.Snapshot answer =
+          runWithRetries(new Callable<com.google.api.services.compute.model.Snapshot>() {
+            @Override
+            public com.google.api.services.compute.model.Snapshot call() {
+              return computeRpc.getSnapshot(snapshot, optionsMap);
+            }
+          }, options().retryParams(), EXCEPTION_HANDLER);
+      return answer == null ? null : Snapshot.fromPb(this, answer);
+    } catch (RetryHelper.RetryHelperException e) {
+      throw ComputeException.translateAndThrow(e);
+    }
+  }
+
+  @Override
+  public Page<Snapshot> listSnapshots(SnapshotListOption... options) {
+    return listSnapshots(options(), optionMap(options));
+  }
+
+  private static Page<Snapshot> listSnapshots(final ComputeOptions serviceOptions,
+      final Map<ComputeRpc.Option, ?> optionsMap) {
+    try {
+      ComputeRpc.Tuple<String, Iterable<com.google.api.services.compute.model.Snapshot>> result =
+          runWithRetries(new Callable<ComputeRpc.Tuple<String,
+              Iterable<com.google.api.services.compute.model.Snapshot>>>() {
+            @Override
+            public ComputeRpc.Tuple<String,
+                Iterable<com.google.api.services.compute.model.Snapshot>> call() {
+              return serviceOptions.rpc().listSnapshots(optionsMap);
+            }
+          }, serviceOptions.retryParams(), EXCEPTION_HANDLER);
+      String cursor = result.x();
+      Iterable<Snapshot> snapshots = Iterables.transform(
+          result.y() == null ? ImmutableList.<com.google.api.services.compute.model.Snapshot>of()
+              : result.y(),
+          new Function<com.google.api.services.compute.model.Snapshot, Snapshot>() {
+            @Override
+            public Snapshot apply(com.google.api.services.compute.model.Snapshot snapshot) {
+              return Snapshot.fromPb(serviceOptions.service(), snapshot);
+            }
+          });
+      return new PageImpl<>(new SnapshotPageFetcher(serviceOptions, cursor, optionsMap), cursor,
+          snapshots);
+    } catch (RetryHelper.RetryHelperException e) {
+      throw ComputeException.translateAndThrow(e);
+    }
+  }
+
+  @Override
+  public Operation deleteSnapshot(final SnapshotId snapshot, OperationOption... options) {
+    final Map<ComputeRpc.Option, ?> optionsMap = optionMap(options);
+    try {
+      com.google.api.services.compute.model.Operation answer =
+          runWithRetries(new Callable<com.google.api.services.compute.model.Operation>() {
+            @Override
+            public com.google.api.services.compute.model.Operation call() {
+              return computeRpc.deleteSnapshot(snapshot.snapshot(), optionsMap);
+            }
+          }, options().retryParams(), EXCEPTION_HANDLER);
+      return answer == null ? null : Operation.fromPb(this, answer);
+    } catch (RetryHelper.RetryHelperException e) {
+      throw ComputeException.translateAndThrow(e);
+    }
+  }
+
+  @Override
+  public Operation deleteSnapshot(final String snapshot, OperationOption... options) {
+    return deleteSnapshot(SnapshotId.of(snapshot));
+  }
+
   private Map<ComputeRpc.Option, ?> optionMap(Option... options) {
     Map<ComputeRpc.Option, Object> optionMap = Maps.newEnumMap(ComputeRpc.Option.class);
     for (Option option : options) {