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FHIR converter is a Java based library that enables converting Hl7v2 messages to FHIR resources

There is a newer version: 1.0.19

/*
 * (C) Copyright IBM Corp. 2020
 *
 * SPDX-License-Identifier: Apache-2.0
 */
package io.github.linuxforhealth.hl7.resource;

import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import io.github.linuxforhealth.api.ResourceModel;
import io.github.linuxforhealth.core.Constants;
import io.github.linuxforhealth.core.ObjectMapperUtil;
import io.github.linuxforhealth.core.config.ConverterConfiguration;
import io.github.linuxforhealth.hl7.message.HL7MessageModel;

/**
 * Reads resources. If the configuration file has base path defined (base.path.resource) then the
 * resources are loaded from that path. If the configuration is not defined then default path would
 * be used.
 * 
 *
 * @author pbhallam
 */
public class ResourceReader {

  private final Logger LOGGER = LoggerFactory.getLogger(ResourceReader.class);

  private static ResourceReader reader;

  private final ConverterConfiguration converterConfig = ConverterConfiguration.getInstance();

  /**
   * Loads a file resource configuration, returning a String
   * @param fileResourceConfiguration The configuration resource to load
   * @return String
   * @throws IOException if an error occurs loading the file resource
   */
  private static String loadFileResource(File fileResourceConfiguration) throws IOException {
    return FileUtils.readFileToString(fileResourceConfiguration, StandardCharsets.UTF_8);
  }

  /**
   * Loads a class path configuration resource, returning a String
   * @param resourceConfigurationPath The class path configuration resource
   * @return String the resource content
   * @throws IOException if an error occurs loading the configuration resource
   */
  private static String loadClassPathResource(String resourceConfigurationPath) throws IOException {
    return IOUtils.resourceToString(resourceConfigurationPath, StandardCharsets.UTF_8,
        ResourceReader.class.getClassLoader());
  }

  /**
   * Loads a file based resource using a two pass approach.
   * The first pass attempts to load the resource from the file system.
   * if the file is not found on the file system, the resource is loaded from the classpath.
   * @param resourcePath The relative path to the resource (hl7/, fhir/, etc)
   * @return The resource as a String
   */
  public String getResource(String resourcePath) {
    Path filePath = Paths.get(converterConfig.getResourceFolder(), resourcePath);
    String resource;

    try {
      if (filePath != null && filePath.toFile().exists()) {
        resource = loadFileResource(filePath.toFile());
      } else {
        resource = loadClassPathResource(resourcePath);
      }
    } catch (IOException ioEx) {
      String msg = "Unable to load resource " + resourcePath;
      throw new IllegalArgumentException(msg, ioEx);
    }
    return resource;
  }

  public Map getMessageTemplates() throws IOException {
    Map messagetemplates = new HashMap<>();
    List