Exists method added (#3769)

Author: elisheva-qlogic

google-cloud-clients/google-cloud-bigtable-admin/src/main/java/com/google/cloud/bigtable/admin/v2/BigtableTableAdminClient.java

@@ -20,6 +20,7 @@
 import com.google.api.core.ApiFuture;
 import com.google.api.core.ApiFutures;
 import com.google.api.gax.rpc.ApiExceptions;
+import com.google.api.gax.rpc.NotFoundException;
 import com.google.bigtable.admin.v2.DeleteTableRequest;
 import com.google.bigtable.admin.v2.DropRowRangeRequest;
 import com.google.bigtable.admin.v2.GetTableRequest;
@@ -323,6 +324,65 @@ public ApiFuture<Void> deleteTableAsync(String tableId) {
     return transformToVoid(this.stub.deleteTableCallable().futureCall(request));
   }
 
+  /**
+   * Checks if the table specified by the tableId exists
+   *
+   * <p>Sample code:
+   *
+   * <pre>{@code
+   * if(client.exists("my-table")) {
+   *   System.out.println("Table exists");
+   * }
+   * }</pre>
+   */
+  public boolean exists(String tableId) {
+    return ApiExceptions.callAndTranslateApiException(existsAsync(tableId));
+  }
+
+  /**
+   * Asynchronously checks if the table specified by the tableId exists
+   *
+   * <p>Sample code:
+   *
+   * <pre>{@code
+   * ApiFuture<Boolean> found = client.existsAsync("my-table");
+   *
+   * ApiFutures.addCallback(
+   *  found,
+   *  new ApiFutureCallback<Boolean>() {
+   *    public void onSuccess(Boolean found) {
+   *      if (found) {
+   *        System.out.println("Table exists");
+   *      } else {
+   *        System.out.println("Table not found");
+   *      }
+   *    }
+   *
+   *    public void onFailure(Throwable t) {
+   *      t.printStackTrace();
+   *    }
+   *  },
+   *  MoreExecutors.directExecutor()
+   * );
+   * }</pre>
+   */
+  public ApiFuture<Boolean> existsAsync(String tableId) {
+
+    ApiFuture<Table> protoFuture = getTableAsync(tableId, com.google.bigtable.admin.v2.Table.View.NAME_ONLY);
+
+    ApiFuture<Boolean> existsFuture = ApiFutures.transform(protoFuture, new ApiFunction<Table, Boolean>() {
+      @Override public Boolean apply(Table ignored) {
+        return true;
+      }
+    }, MoreExecutors.directExecutor());
+
+    return ApiFutures.catching(existsFuture, NotFoundException.class, new ApiFunction<NotFoundException, Boolean>() {
+      @Override public Boolean apply(NotFoundException ignored) {
+        return false;
+      }
+    }, MoreExecutors.directExecutor());
+  }
+
   /**
    * Gets the table metadata by tableId.
    *
@@ -373,8 +433,13 @@ public Table getTable(String tableId) {
    */
   @SuppressWarnings("WeakerAccess")
   public ApiFuture<Table> getTableAsync(String tableId) {
+    return getTableAsync(tableId, com.google.bigtable.admin.v2.Table.View.SCHEMA_VIEW);
+  }
+
+  private ApiFuture<Table> getTableAsync(String tableId, com.google.bigtable.admin.v2.Table.View view) {
     GetTableRequest request = GetTableRequest.newBuilder()
         .setName(getTableName(tableId))
+        .setView(view)
         .build();
 
     return transformToTableResponse(

google-cloud-clients/google-cloud-bigtable-admin/src/test/java/com/google/cloud/bigtable/admin/v2/BigtableTableAdminClientTest.java

@@ -19,6 +19,8 @@
 
 import com.google.api.core.ApiFuture;
 import com.google.api.core.ApiFutures;
+import com.google.api.gax.grpc.GrpcStatusCode;
+import com.google.api.gax.rpc.NotFoundException;
 import com.google.api.gax.rpc.UnaryCallable;
 import com.google.bigtable.admin.v2.ColumnFamily;
 import com.google.bigtable.admin.v2.DeleteTableRequest;
@@ -28,6 +30,7 @@
 import com.google.bigtable.admin.v2.InstanceName;
 import com.google.bigtable.admin.v2.ListTablesRequest;
 import com.google.bigtable.admin.v2.ModifyColumnFamiliesRequest.Modification;
+import com.google.bigtable.admin.v2.Table.View;
 import com.google.bigtable.admin.v2.TableName;
 import com.google.cloud.bigtable.admin.v2.BaseBigtableTableAdminClient.ListTablesPage;
 import com.google.cloud.bigtable.admin.v2.BaseBigtableTableAdminClient.ListTablesPagedResponse;
@@ -40,9 +43,12 @@
 import com.google.protobuf.Empty;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicBoolean;
+
+import io.grpc.Status;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.mockito.Matchers;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.mockito.invocation.InvocationOnMock;
@@ -184,6 +190,7 @@ public void testGetTable() {
     // Setup
     GetTableRequest expectedRequest = GetTableRequest.newBuilder()
         .setName(TABLE_NAME.toString())
+        .setView(View.SCHEMA_VIEW)
         .build();
 
     com.google.bigtable.admin.v2.Table expectedResponse = com.google.bigtable.admin.v2.Table
@@ -303,4 +310,38 @@ public ApiFuture<Void> answer(InvocationOnMock invocationOnMock) throws Throwabl
     // Verify
     assertThat(wasCalled.get()).isTrue();
   }
+
+  @Test
+  public void testExistsTrue() {
+    // Setup
+    com.google.bigtable.admin.v2.Table expectedResponse =
+        com.google.bigtable.admin.v2.Table.newBuilder()
+            .setName(TABLE_NAME.toString())
+            .build();
+
+    Mockito.when(mockGetTableCallable.futureCall(Matchers.any(GetTableRequest.class)))
+        .thenReturn(ApiFutures.immediateFuture(expectedResponse));
+
+    // Execute
+    boolean found = adminClient.exists(TABLE_NAME.getTable());
+
+    // Verify
+    assertThat(found).isTrue();
+  }
+
+  @Test
+  public void testExistsFalse() {
+    // Setup
+    NotFoundException exception =
+        new NotFoundException("fake error", null, GrpcStatusCode.of(Status.Code.NOT_FOUND), false);
+
+    Mockito.when(mockGetTableCallable.futureCall(Matchers.any(GetTableRequest.class)))
+            .thenReturn(ApiFutures.<com.google.bigtable.admin.v2.Table>immediateFailedFuture(exception));
+
+    // Execute
+    boolean found = adminClient.exists(TABLE_NAME.getTable());
+
+    // Verify
+    assertThat(found).isFalse();
+  }
 }