Implement ResultSetMetadata and use it everwhere we operate on metadata

Also fix AbstractProtoStructReaderTest which was using the wrong runner
and not executing any tests. Fixes a couple test bugs as well.

Change-Id: Ia59459f93dd38046e9ac22995191becaad6ea44e

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/AbstractProtoStructReader.java

@@ -15,7 +15,6 @@
  */
 package com.google.cloud.bigtable.data.v2.internal;
 
-import com.google.api.core.BetaApi;
 import com.google.api.core.InternalApi;
 import com.google.bigtable.v2.Type;
 import com.google.bigtable.v2.Value;
@@ -34,7 +33,6 @@
 import org.threeten.bp.Instant;
 
 @InternalApi
-@BetaApi
 public abstract class AbstractProtoStructReader implements StructReader {
 
   abstract List<Value> values();

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/ColumnMetadataImpl.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * 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
+ *
+ *     https://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 com.google.cloud.bigtable.data.v2.internal;
+
+import com.google.api.core.InternalApi;
+import com.google.auto.value.AutoValue;
+import com.google.bigtable.v2.Type;
+import com.google.cloud.bigtable.data.v2.models.sql.ColumnMetadata;
+
+/**
+ * Implementation of {@link ColumnMetadata} using AutoValue
+ *
+ * <p>This is considered an internal implementation detail and not meant to be used by applications.
+ */
+@InternalApi("For internal use only")
+@AutoValue
+public abstract class ColumnMetadataImpl implements ColumnMetadata {
+  public static ColumnMetadata create(String name, Type type) {
+    return new AutoValue_ColumnMetadataImpl(name, type);
+  }
+
+  static ColumnMetadata fromProto(com.google.bigtable.v2.ColumnMetadata proto) {
+    return create(proto.getName(), proto.getType());
+  }
+}

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/ProtoResultSetMetadata.java

@@ -0,0 +1,134 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * 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
+ *
+ *     https://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 com.google.cloud.bigtable.data.v2.internal;
+
+import com.google.api.core.InternalApi;
+import com.google.bigtable.v2.ProtoSchema;
+import com.google.bigtable.v2.ResultSetMetadata.SchemaCase;
+import com.google.bigtable.v2.Type;
+import com.google.cloud.bigtable.data.v2.models.sql.ColumnMetadata;
+import com.google.cloud.bigtable.data.v2.models.sql.ResultSetMetadata;
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import javax.annotation.Nullable;
+
+/**
+ * Implementation of {@link ResultSetMetadata} using an underlying protobuf schema.
+ *
+ * <p>This is considered an internal implementation detail and not meant to be used by applications.
+ */
+@InternalApi
+public class ProtoResultSetMetadata implements ResultSetMetadata {
+
+  // It is valid for a select query to return columns with the same name. This marker is used
+  // internally in the client to designate that getting a value by column name is invalid and will
+  // be converted into an exception.
+  private static final int AMBIGUOUS_FIELD_MARKER = -1;
+
+  private final List<ColumnMetadata> columns;
+  private final Map<String, Integer> columnNameMapping;
+
+  public static ResultSetMetadata create(List<ColumnMetadata> columns) {
+    return new ProtoResultSetMetadata(columns);
+  }
+
+  private ProtoResultSetMetadata(List<ColumnMetadata> columns) {
+    this.columns = ImmutableList.copyOf(columns);
+    // consider deferring building this until first get-by-column-name call
+    this.columnNameMapping = buildColumnNameMapping(columns);
+  }
+
+  @Override
+  public List<ColumnMetadata> getColumns() {
+    return columns;
+  }
+
+  @Override
+  public Type getColumnType(int columnIndex) {
+    return columns.get(columnIndex).type();
+  }
+
+  @Override
+  public Type getColumnType(String columnName) {
+    return getColumnType(getColumnIndex(columnName));
+  }
+
+  @Override
+  public int getColumnIndex(String columnName) {
+    Integer index = columnNameMapping.get(columnName);
+    if (index == null) {
+      throw new IllegalArgumentException("Column name not found: " + columnName);
+    }
+    int unboxedIndex = index;
+    if (unboxedIndex == AMBIGUOUS_FIELD_MARKER) {
+      throw new IllegalArgumentException(
+          "Ambiguous column name: " + columnName + ". Same name is used for multiple columns.");
+    }
+    return unboxedIndex;
+  }
+
+  @InternalApi
+  public static ResultSetMetadata fromProto(com.google.bigtable.v2.ResultSetMetadata proto) {
+    Preconditions.checkState(
+        proto.getSchemaCase().equals(SchemaCase.PROTO_SCHEMA),
+        "Unsupported schema type: %s",
+        proto.getSchemaCase().name());
+    ProtoSchema schema = proto.getProtoSchema();
+    validateSchema(schema);
+    ImmutableList.Builder<ColumnMetadata> columnsBuilder = ImmutableList.builder();
+    for (com.google.bigtable.v2.ColumnMetadata protoColumn : schema.getColumnsList()) {
+      columnsBuilder.add(ColumnMetadataImpl.fromProto(protoColumn));
+    }
+    return create(columnsBuilder.build());
+  }
+
+  private static void validateSchema(ProtoSchema schema) {
+    List<com.google.bigtable.v2.ColumnMetadata> columns = schema.getColumnsList();
+    Preconditions.checkState(!columns.isEmpty(), "columns cannot be empty");
+    for (com.google.bigtable.v2.ColumnMetadata column : columns) {
+      Preconditions.checkState(
+          column.getType().getKindCase() != Type.KindCase.KIND_NOT_SET,
+          "Column type cannot be empty");
+    }
+  }
+
+  private Map<String, Integer> buildColumnNameMapping(List<ColumnMetadata> columns) {
+    HashMap<String, Integer> mapping = new HashMap<>(columns.size());
+    for (int i = 0; i < columns.size(); i++) {
+      ColumnMetadata column = columns.get(i);
+      if (mapping.containsKey(column.name())) {
+        mapping.put(column.name(), AMBIGUOUS_FIELD_MARKER);
+      } else {
+        mapping.put(column.name(), i);
+      }
+    }
+    return ImmutableMap.copyOf(mapping);
+  }
+
+  @Override
+  public boolean equals(@Nullable Object other) {
+    if (other instanceof ProtoResultSetMetadata) {
+      ProtoResultSetMetadata o = (ProtoResultSetMetadata) other;
+      // columnNameMapping is derived from columns, so we only need to compare columns
+      return columns.equals(o.columns);
+    }
+    return false;
+  }
+}

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/ProtoSqlRow.java

@@ -15,47 +15,36 @@
  */
 package com.google.cloud.bigtable.data.v2.internal;
 
-import com.google.api.core.BetaApi;
 import com.google.api.core.InternalApi;
 import com.google.auto.value.AutoValue;
-import com.google.bigtable.v2.ColumnMetadata;
 import com.google.bigtable.v2.Type;
 import com.google.bigtable.v2.Value;
+import com.google.cloud.bigtable.data.v2.models.sql.ResultSetMetadata;
 import java.util.List;
 
 @InternalApi
-@BetaApi
 @AutoValue
 public abstract class ProtoSqlRow extends AbstractProtoStructReader implements SqlRow {
   /**
    * Creates a new SqlRow
    *
-   * @param schema list of column metadata for each column
+   * @param metadata the {@link ResultSetMetadata} for the results
    * @param values list of the values for each column
    */
-  public static ProtoSqlRow create(List<ColumnMetadata> schema, List<Value> values) {
-    return new AutoValue_ProtoSqlRow(values, schema);
+  public static ProtoSqlRow create(ResultSetMetadata metadata, List<Value> values) {
+    return new AutoValue_ProtoSqlRow(values, metadata);
   }
 
-  /** List of {@link ColumnMetadata} describing the schema of the row. */
-  abstract List<ColumnMetadata> schema();
+  /** {@link ResultSetMetadata} describing the schema of the row. */
+  abstract ResultSetMetadata metadata();
 
-  // This is a temporary hack. The type/metadata wrappers will provide an efficient way to lookup
-  // fields and type by columnName
-  // TODO(jackdingilian): replace with efficient lookup
-  // TODO(jackdingilian): fail on requests for column that appears multiple times
   @Override
   public int getColumnIndex(String columnName) {
-    for (int i = 0; i < schema().size(); i++) {
-      if (schema().get(i).getName().equals(columnName)) {
-        return i;
-      }
-    }
-    throw new IllegalArgumentException("No field found with name: " + columnName);
+    return metadata().getColumnIndex(columnName);
   }
 
   @Override
   public Type getColumnType(int columnIndex) {
-    return schema().get(columnIndex).getType();
+    return metadata().getColumnType(columnIndex);
   }
 }

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/ProtoStruct.java

@@ -15,7 +15,6 @@
  */
 package com.google.cloud.bigtable.data.v2.internal;
 
-import com.google.api.core.BetaApi;
 import com.google.api.core.InternalApi;
 import com.google.auto.value.AutoValue;
 import com.google.bigtable.v2.ArrayValue;
@@ -29,7 +28,6 @@
  *
  * <p>This is considered an internal implementation detail and not meant to be used by applications.
  */
-@BetaApi
 @InternalApi("For internal use only")
 @AutoValue
 public abstract class ProtoStruct extends AbstractProtoStructReader implements Struct {

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/ResultSetImpl.java

@@ -15,12 +15,11 @@
  */
 package com.google.cloud.bigtable.data.v2.internal;
 
-import com.google.api.core.BetaApi;
 import com.google.api.core.InternalApi;
 import com.google.api.gax.rpc.ServerStream;
-import com.google.bigtable.v2.ResultSetMetadata;
 import com.google.cloud.Date;
 import com.google.cloud.bigtable.data.v2.models.sql.ResultSet;
+import com.google.cloud.bigtable.data.v2.models.sql.ResultSetMetadata;
 import com.google.cloud.bigtable.data.v2.models.sql.Struct;
 import com.google.cloud.bigtable.data.v2.models.sql.StructReader;
 import com.google.common.base.Preconditions;
@@ -39,7 +38,6 @@
  *
  * <p>This is considered an internal implementation detail and not meant to be used by applications.
  */
-@BetaApi
 @InternalApi("For internal use only")
 public class ResultSetImpl implements ResultSet, StructReader {
 

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/SqlRow.java

@@ -15,12 +15,10 @@
  */
 package com.google.cloud.bigtable.data.v2.internal;
 
-import com.google.api.core.BetaApi;
 import com.google.api.core.InternalApi;
 import com.google.cloud.bigtable.data.v2.models.sql.StructReader;
 import java.io.Serializable;
 
 /** Internal implementation detail that provides access to row data for SQL requests. */
 @InternalApi
-@BetaApi
 public interface SqlRow extends StructReader, Serializable {}

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/SqlRowMergerUtil.java

@@ -18,7 +18,7 @@
 import com.google.api.core.BetaApi;
 import com.google.api.core.InternalApi;
 import com.google.bigtable.v2.ExecuteQueryResponse;
-import com.google.bigtable.v2.ResultSetMetadata;
+import com.google.cloud.bigtable.data.v2.models.sql.ResultSetMetadata;
 import com.google.cloud.bigtable.data.v2.stub.sql.SqlRowMerger;
 import com.google.common.collect.ImmutableList;
 import java.util.List;

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/models/sql/ColumnMetadata.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * 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
+ *
+ *     https://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 com.google.cloud.bigtable.data.v2.models.sql;
+
+import com.google.api.core.BetaApi;
+import com.google.bigtable.v2.Type;
+
+/** Represents the metadata for a column in a {@link ResultSet} */
+@BetaApi
+public interface ColumnMetadata {
+  /** The name of the column. Returns Empty string if the column has no name */
+  String name();
+
+  /** The {@link Type} of the column */
+  // TODO(jackdingilian): replace with type wrapper
+  Type type();
+}

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/models/sql/ResultSet.java

@@ -15,7 +15,7 @@
  */
 package com.google.cloud.bigtable.data.v2.models.sql;
 
-import com.google.bigtable.v2.ResultSetMetadata;
+import com.google.api.core.BetaApi;
 import java.util.concurrent.ExecutionException;
 
 /**
@@ -39,6 +39,7 @@
  * <p>{@code ResultSet} implementations are not required to be thread-safe: the thread that asked
  * for a ResultSet must be the one that interacts with it.
  */
+@BetaApi
 public interface ResultSet extends StructReader, AutoCloseable {
 
   /**
@@ -48,10 +49,9 @@ public interface ResultSet extends StructReader, AutoCloseable {
   boolean next();
 
   /**
-   * Returns the metadata for the ResultSet. Blocks until the underlying stream receives the
-   * metadata.
+   * Returns the {@link ResultSetMetadata} for the ResultSet. Blocks until the underlying request
+   * receives the metadata.
    */
-  // TODO replace with a wrapper around the protos (and update doc string)
   ResultSetMetadata getMetadata() throws ExecutionException, InterruptedException;
 
   /**