Add support for selected fields to blob get and list

gcloud-java-storage/src/main/java/com/google/gcloud/spi/DefaultStorageRpc.java

@@ -15,6 +15,7 @@
 package com.google.gcloud.spi;
 
 import static com.google.gcloud.spi.StorageRpc.Option.DELIMITER;
+import static com.google.gcloud.spi.StorageRpc.Option.FIELDS;
 import static com.google.gcloud.spi.StorageRpc.Option.IF_GENERATION_MATCH;
 import static com.google.gcloud.spi.StorageRpc.Option.IF_GENERATION_NOT_MATCH;
 import static com.google.gcloud.spi.StorageRpc.Option.IF_METAGENERATION_MATCH;
@@ -150,6 +151,7 @@ public Tuple<String, Iterable<Bucket>> list(Map<Option, ?> options) {
           .setPrefix(PREFIX.getString(options))
           .setMaxResults(MAX_RESULTS.getLong(options))
           .setPageToken(PAGE_TOKEN.getString(options))
+          .setFields(FIELDS.getString(options))
           .execute();
       return Tuple.<String, Iterable<Bucket>>of(buckets.getNextPageToken(), buckets.getItems());
     } catch (IOException ex) {
@@ -168,6 +170,7 @@ public Tuple<String, Iterable<StorageObject>> list(String bucket, Map<Option, ?>
           .setPrefix(PREFIX.getString(options))
           .setMaxResults(MAX_RESULTS.getLong(options))
           .setPageToken(PAGE_TOKEN.getString(options))
+          .setFields(FIELDS.getString(options))
           .execute();
       return Tuple.<String, Iterable<StorageObject>>of(
           objects.getNextPageToken(), objects.getItems());
@@ -184,6 +187,7 @@ public Bucket get(Bucket bucket, Map<Option, ?> options) {
           .setProjection(DEFAULT_PROJECTION)
           .setIfMetagenerationMatch(IF_METAGENERATION_MATCH.getLong(options))
           .setIfMetagenerationNotMatch(IF_METAGENERATION_NOT_MATCH.getLong(options))
+          .setFields(FIELDS.getString(options))
           .execute();
     } catch (IOException ex) {
       throw translate(ex);
@@ -207,7 +211,8 @@ private Storage.Objects.Get getRequest(StorageObject object, Map<Option, ?> opti
         .setIfMetagenerationMatch(IF_METAGENERATION_MATCH.getLong(options))
         .setIfMetagenerationNotMatch(IF_METAGENERATION_NOT_MATCH.getLong(options))
         .setIfGenerationMatch(IF_GENERATION_MATCH.getLong(options))
-        .setIfGenerationNotMatch(IF_GENERATION_NOT_MATCH.getLong(options));
+        .setIfGenerationNotMatch(IF_GENERATION_NOT_MATCH.getLong(options))
+        .setFields(FIELDS.getString(options));
   }
 
   @Override

gcloud-java-storage/src/main/java/com/google/gcloud/spi/StorageRpc.java

@@ -47,7 +47,8 @@ enum Option {
     MAX_RESULTS("maxResults"),
     PAGE_TOKEN("pageToken"),
     DELIMITER("delimiter"),
-    VERSIONS("versions");
+    VERSIONS("versions"),
+    FIELDS("fields");
 
     private final String value;
 

gcloud-java-storage/src/main/java/com/google/gcloud/storage/BatchRequest.java

@@ -18,6 +18,7 @@
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
+import com.google.gcloud.storage.Storage.BlobGetOption;
 import com.google.gcloud.storage.Storage.BlobSourceOption;
 import com.google.gcloud.storage.Storage.BlobTargetOption;
 
@@ -35,13 +36,13 @@ public final class BatchRequest implements Serializable {
 
   private final Map<BlobId, Iterable<BlobSourceOption>> toDelete;
   private final Map<BlobInfo, Iterable<BlobTargetOption>> toUpdate;
-  private final Map<BlobId, Iterable<BlobSourceOption>> toGet;
+  private final Map<BlobId, Iterable<BlobGetOption>> toGet;
 
   public static class Builder {
 
     private Map<BlobId, Iterable<BlobSourceOption>> toDelete = new LinkedHashMap<>();
     private Map<BlobInfo, Iterable<BlobTargetOption>> toUpdate = new LinkedHashMap<>();
-    private Map<BlobId, Iterable<BlobSourceOption>> toGet = new LinkedHashMap<>();
+    private Map<BlobId, Iterable<BlobGetOption>> toGet = new LinkedHashMap<>();
 
     private Builder() {}
 
@@ -72,15 +73,15 @@ public Builder update(BlobInfo blobInfo, BlobTargetOption... options) {
     /**
      * Retrieve metadata for the given blob.
      */
-    public Builder get(String bucket, String blob, BlobSourceOption... options) {
+    public Builder get(String bucket, String blob, BlobGetOption... options) {
       toGet.put(BlobId.of(bucket, blob), Lists.newArrayList(options));
       return this;
     }
 
     /**
      * Retrieve metadata for the given blob.
      */
-    public Builder get(BlobId blob, BlobSourceOption... options) {
+    public Builder get(BlobId blob, BlobGetOption... options) {
       toGet.put(blob, Lists.newArrayList(options));
       return this;
     }
@@ -120,7 +121,7 @@ public Map<BlobInfo, Iterable<BlobTargetOption>> toUpdate() {
     return toUpdate;
   }
 
-  public Map<BlobId, Iterable<BlobSourceOption>> toGet() {
+  public Map<BlobId, Iterable<BlobGetOption>> toGet() {
     return toGet;
   }
 

gcloud-java-storage/src/main/java/com/google/gcloud/storage/Blob.java

@@ -18,7 +18,8 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
-import static com.google.gcloud.storage.Blob.BlobSourceOption.convert;
+import static com.google.gcloud.storage.Blob.BlobSourceOption.toSourceOptions;
+import static com.google.gcloud.storage.Blob.BlobSourceOption.toGetOptions;
 
 import com.google.common.base.Function;
 import com.google.common.collect.Lists;
@@ -29,6 +30,7 @@
 import com.google.gcloud.storage.Storage.SignUrlOption;
 
 import java.net.URL;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
@@ -56,7 +58,7 @@ private BlobSourceOption(StorageRpc.Option rpcOption) {
       super(rpcOption, null);
     }
 
-    private Storage.BlobSourceOption convert(BlobInfo blobInfo) {
+    private Storage.BlobSourceOption toSourceOptions(BlobInfo blobInfo) {
       switch (rpcOption()) {
         case IF_GENERATION_MATCH:
           return Storage.BlobSourceOption.generationMatch(blobInfo.generation());
@@ -71,6 +73,21 @@ private Storage.BlobSourceOption convert(BlobInfo blobInfo) {
       }
     }
 
+    private Storage.BlobGetOption toGetOption(BlobInfo blobInfo) {
+      switch (rpcOption()) {
+        case IF_GENERATION_MATCH:
+          return Storage.BlobGetOption.generationMatch(blobInfo.generation());
+        case IF_GENERATION_NOT_MATCH:
+          return Storage.BlobGetOption.generationNotMatch(blobInfo.generation());
+        case IF_METAGENERATION_MATCH:
+          return Storage.BlobGetOption.metagenerationMatch(blobInfo.metageneration());
+        case IF_METAGENERATION_NOT_MATCH:
+          return Storage.BlobGetOption.metagenerationNotMatch(blobInfo.metageneration());
+        default:
+          throw new AssertionError("Unexpected enum value");
+      }
+    }
+
     public static BlobSourceOption generationMatch() {
       return new BlobSourceOption(StorageRpc.Option.IF_GENERATION_MATCH);
     }
@@ -87,11 +104,21 @@ public static BlobSourceOption metagenerationNotMatch() {
       return new BlobSourceOption(StorageRpc.Option.IF_METAGENERATION_NOT_MATCH);
     }
 
-    static Storage.BlobSourceOption[] convert(BlobInfo blobInfo, BlobSourceOption... options) {
+    static Storage.BlobSourceOption[] toSourceOptions(BlobInfo blobInfo,
+        BlobSourceOption... options) {
       Storage.BlobSourceOption[] convertedOptions = new Storage.BlobSourceOption[options.length];
       int index = 0;
       for (BlobSourceOption option : options) {
-        convertedOptions[index++] = option.convert(blobInfo);
+        convertedOptions[index++] = option.toSourceOptions(blobInfo);
+      }
+      return convertedOptions;
+    }
+
+    static Storage.BlobGetOption[] toGetOptions(BlobInfo blobInfo, BlobSourceOption... options) {
+      Storage.BlobGetOption[] convertedOptions = new Storage.BlobGetOption[options.length];
+      int index = 0;
+      for (BlobSourceOption option : options) {
+        convertedOptions[index++] = option.toGetOption(blobInfo);
       }
       return convertedOptions;
     }
@@ -100,7 +127,7 @@ static Storage.BlobSourceOption[] convert(BlobInfo blobInfo, BlobSourceOption...
   /**
    * Constructs a {@code Blob} object for the provided {@code BlobInfo}. The storage service is used
    * to issue requests.
-   * 
+   *
    * @param storage the storage service used for issuing requests
    * @param info blob's info
    */
@@ -112,7 +139,7 @@ public Blob(Storage storage, BlobInfo info) {
   /**
    * Creates a {@code Blob} object for the provided bucket and blob names. Performs an RPC call to
    * get the latest blob information.
-   * 
+   *
    * @param storage the storage service used for issuing requests
    * @param bucket bucket's name
    * @param blob blob's name
@@ -126,7 +153,7 @@ public static Blob load(Storage storage, String bucket, String blob) {
   /**
    * Creates a {@code Blob} object for the provided {@code blobId}. Performs an RPC call to get the
    * latest blob information.
-   * 
+   *
    * @param storage the storage service used for issuing requests
    * @param blobId blob's identifier
    * @return the {@code Blob} object or {@code null} if not found.
@@ -159,7 +186,10 @@ public BlobId id() {
    * @throws StorageException upon failure
    */
   public boolean exists(BlobSourceOption... options) {
-    return storage.get(info.blobId(), convert(info, options)) != null;
+    int length = options.length;
+    Storage.BlobGetOption[] getOptions = Arrays.copyOf(toGetOptions(info, options), length + 1);
+    getOptions[length] = Storage.BlobGetOption.fields();
+    return storage.get(info.blobId(), getOptions) != null;
   }
 
   /**
@@ -180,7 +210,7 @@ public byte[] content(Storage.BlobSourceOption... options) {
    * @throws StorageException upon failure
    */
   public Blob reload(BlobSourceOption... options) {
-    return new Blob(storage, storage.get(info.blobId(), convert(info, options)));
+    return new Blob(storage, storage.get(info.blobId(), toGetOptions(info, options)));
   }
 
   /**
@@ -224,7 +254,7 @@ public Blob update(BlobInfo blobInfo, BlobTargetOption... options) {
    */
   public CopyWriter copyTo(BlobId targetBlob, BlobSourceOption... options) {
     CopyRequest copyRequest = CopyRequest.builder().source(info.bucket(), info.name())
-        .sourceOptions(convert(info, options)).target(targetBlob).build();
+        .sourceOptions(toSourceOptions(info, options)).target(targetBlob).build();
     return storage.copy(copyRequest);
   }
 
@@ -236,7 +266,7 @@ public CopyWriter copyTo(BlobId targetBlob, BlobSourceOption... options) {
    * @throws StorageException upon failure
    */
   public boolean delete(BlobSourceOption... options) {
-    return storage.delete(info.blobId(), convert(info, options));
+    return storage.delete(info.blobId(), toSourceOptions(info, options));
   }
 
   /**
@@ -275,7 +305,7 @@ public CopyWriter copyTo(String targetBucket, String targetBlob, BlobSourceOptio
    * @throws StorageException upon failure
    */
   public BlobReadChannel reader(BlobSourceOption... options) {
-    return storage.reader(info.blobId(), convert(info, options));
+    return storage.reader(info.blobId(), toSourceOptions(info, options));
   }
 
   /**

gcloud-java-storage/src/main/java/com/google/gcloud/storage/Bucket.java

@@ -18,23 +18,26 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.gcloud.storage.Bucket.BucketSourceOption.toGetOptions;
+import static com.google.gcloud.storage.Bucket.BucketSourceOption.toSourceOptions;
 
 import com.google.common.base.Function;
 import com.google.common.base.MoreObjects;
 import com.google.common.collect.Iterators;
 import com.google.gcloud.PageImpl;
 import com.google.gcloud.Page;
-import com.google.gcloud.storage.Storage.BlobSourceOption;
+import com.google.gcloud.spi.StorageRpc;
+import com.google.gcloud.storage.Storage.BlobGetOption;
 import com.google.gcloud.storage.Storage.BlobTargetOption;
 import com.google.gcloud.storage.Storage.BlobWriteOption;
-import com.google.gcloud.storage.Storage.BucketSourceOption;
 import com.google.gcloud.storage.Storage.BucketTargetOption;
 
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.ObjectInputStream;
 import java.io.Serializable;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
@@ -119,6 +122,66 @@ public boolean equals(Object obj) {
     }
   }
 
+  public static class BucketSourceOption extends Option {
+
+    private static final long serialVersionUID = 6928872234155522371L;
+
+    private BucketSourceOption(StorageRpc.Option rpcOption) {
+      super(rpcOption, null);
+    }
+
+    private Storage.BucketSourceOption toSourceOptions(BucketInfo bucketInfo) {
+      switch (rpcOption()) {
+        case IF_METAGENERATION_MATCH:
+          return Storage.BucketSourceOption.metagenerationMatch(bucketInfo.metageneration());
+        case IF_METAGENERATION_NOT_MATCH:
+          return Storage.BucketSourceOption.metagenerationNotMatch(bucketInfo.metageneration());
+        default:
+          throw new AssertionError("Unexpected enum value");
+      }
+    }
+
+    private Storage.BucketGetOption toGetOption(BucketInfo bucketInfo) {
+      switch (rpcOption()) {
+        case IF_METAGENERATION_MATCH:
+          return Storage.BucketGetOption.metagenerationMatch(bucketInfo.metageneration());
+        case IF_METAGENERATION_NOT_MATCH:
+          return Storage.BucketGetOption.metagenerationNotMatch(bucketInfo.metageneration());
+        default:
+          throw new AssertionError("Unexpected enum value");
+      }
+    }
+
+    public static BucketSourceOption metagenerationMatch() {
+      return new BucketSourceOption(StorageRpc.Option.IF_METAGENERATION_MATCH);
+    }
+
+    public static BucketSourceOption metagenerationNotMatch() {
+      return new BucketSourceOption(StorageRpc.Option.IF_METAGENERATION_NOT_MATCH);
+    }
+
+    static Storage.BucketSourceOption[] toSourceOptions(BucketInfo bucketInfo,
+         BucketSourceOption... options) {
+      Storage.BucketSourceOption[] convertedOptions =
+          new Storage.BucketSourceOption[options.length];
+      int index = 0;
+      for (BucketSourceOption option : options) {
+        convertedOptions[index++] = option.toSourceOptions(bucketInfo);
+      }
+      return convertedOptions;
+    }
+
+    static Storage.BucketGetOption[] toGetOptions(BucketInfo bucketInfo,
+        BucketSourceOption... options) {
+      Storage.BucketGetOption[] convertedOptions = new Storage.BucketGetOption[options.length];
+      int index = 0;
+      for (BucketSourceOption option : options) {
+        convertedOptions[index++] = option.toGetOption(bucketInfo);
+      }
+      return convertedOptions;
+    }
+  }
+
   /**
    * Constructs a {@code Bucket} object for the provided {@code BucketInfo}. The storage service is
    * used to issue requests.
@@ -158,8 +221,11 @@ public BucketInfo info() {
    * @return true if this bucket exists, false otherwise
    * @throws StorageException upon failure
    */
-  public boolean exists() {
-    return storage.get(info.name()) != null;
+  public boolean exists(BucketSourceOption... options) {
+    int length = options.length;
+    Storage.BucketGetOption[] getOptions = Arrays.copyOf(toGetOptions(info, options), length + 1);
+    getOptions[length] = Storage.BucketGetOption.fields();
+    return storage.get(info.name(), getOptions) != null;
   }
 
   /**
@@ -170,7 +236,7 @@ public boolean exists() {
    * @throws StorageException upon failure
    */
   public Bucket reload(BucketSourceOption... options) {
-    return new Bucket(storage, storage.get(info.name(), options));
+    return new Bucket(storage, storage.get(info.name(), toGetOptions(info, options)));
   }
 
   /**
@@ -198,7 +264,7 @@ public Bucket update(BucketInfo bucketInfo, BucketTargetOption... options) {
    * @throws StorageException upon failure
    */
   public boolean delete(BucketSourceOption... options) {
-    return storage.delete(info.name(), options);
+    return storage.delete(info.name(), toSourceOptions(info, options));
   }
 
   /**
@@ -221,7 +287,7 @@ public Page<Blob> list(Storage.BlobListOption... options) {
    * @param options blob search options
    * @throws StorageException upon failure
    */
-  public Blob get(String blob, BlobSourceOption... options) {
+  public Blob get(String blob, BlobGetOption... options) {
     return new Blob(storage, storage.get(BlobId.of(info.name(), blob), options));
   }