content: /*
   * Copyright © 2018-2025 Commonwealth Scientific and Industrial Research
   * Organisation (CSIRO) ABN 41 687 119 230.
   *
   * 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 au.csiro.pathling.library.io.source;
  
  import au.csiro.pathling.library.PathlingContext;
  import jakarta.annotation.Nonnull;
  
  /**
   * A class for making FHIR data in Delta tables on the filesystem available for query. It is assumed
   * that the schema of the Delta tables aligns with that of the Pathling FHIR encoders. Delta tables
   * store data in Parquet format internally, so this source uses the parquet extension for file
   * detection.
   *
   * @author John Grimes
   * @author Piotr Szul
   */
  public class DeltaSource extends FileSource {
  
    /**
     * Constructs a DeltaSource with the specified PathlingContext and path.
     *
     * @param context the PathlingContext to use
     * @param path the path to the Delta table directory
     */
    DeltaSource(@Nonnull final PathlingContext context, @Nonnull final String path) {
      super(context, path,
          // Use the "resource name with qualifier" mapper by default, which takes the resource name
          // from the file name and is tolerant of an optional qualifier string.
          FileSource::resourceNameWithQualifierMapper,
          // Delta tables store data in parquet format internally, so we use the parquet extension.
          "parquet",
          context.getSpark().read().format("delta"),
          // Apply no transformations on the data - we assume it has already been processed using the 
          // Pathling FHIR encoders.
          (sourceData, resourceType) -> sourceData);
    }
  
  }
  