001/*
002 * Portions of this software was developed by employees of the National Institute
003 * of Standards and Technology (NIST), an agency of the Federal Government and is
004 * being made available as a public service. Pursuant to title 17 United States
005 * Code Section 105, works of NIST employees are not subject to copyright
006 * protection in the United States. This software may be subject to foreign
007 * copyright. Permission in the United States and in foreign countries, to the
008 * extent that NIST may hold copyright, to use, copy, modify, create derivative
009 * works, and distribute this software and its documentation without fee is hereby
010 * granted on a non-exclusive basis, provided that this notice and disclaimer
011 * of warranty appears in all copies.
012 *
013 * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
014 * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
015 * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
016 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
017 * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
018 * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE.  IN NO EVENT
019 * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
020 * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
021 * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
022 * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
023 * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
024 * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
025 */
026
027package gov.nist.secauto.metaschema.databind.io.yaml;
028
029import org.json.JSONException;
030import org.json.JSONObject;
031import org.yaml.snakeyaml.DumperOptions;
032import org.yaml.snakeyaml.LoaderOptions;
033import org.yaml.snakeyaml.Yaml;
034import org.yaml.snakeyaml.constructor.Constructor;
035import org.yaml.snakeyaml.nodes.Tag;
036import org.yaml.snakeyaml.representer.Representer;
037import org.yaml.snakeyaml.resolver.Resolver;
038
039import java.io.BufferedReader;
040import java.io.IOException;
041import java.nio.charset.StandardCharsets;
042import java.nio.file.Files;
043import java.nio.file.Path;
044import java.util.Map;
045
046import edu.umd.cs.findbugs.annotations.NonNull;
047
048public final class YamlOperations {
049  private static final Yaml YAML_PARSER;
050
051  static {
052    LoaderOptions loaderOptions = new LoaderOptions();
053    loaderOptions.setCodePointLimit(Integer.MAX_VALUE - 1); // 2GB
054    Constructor constructor = new Constructor(loaderOptions);
055    DumperOptions dumperOptions = new DumperOptions();
056    Representer representer = new Representer(dumperOptions);
057    YAML_PARSER = new Yaml(constructor, representer, dumperOptions, loaderOptions, new Resolver() {
058      @Override
059      protected void addImplicitResolvers() {
060        addImplicitResolver(Tag.BOOL, BOOL, "yYnNtTfFoO");
061        addImplicitResolver(Tag.INT, INT, "-+0123456789");
062        addImplicitResolver(Tag.FLOAT, FLOAT, "-+0123456789.");
063        addImplicitResolver(Tag.MERGE, MERGE, "<");
064        addImplicitResolver(Tag.NULL, NULL, "~nN\0");
065        addImplicitResolver(Tag.NULL, EMPTY, null);
066        // addImplicitResolver(Tag.TIMESTAMP, TIMESTAMP, "0123456789");
067      }
068    });
069  }
070
071  private YamlOperations() {
072    // disable construction
073  }
074
075  /**
076   * Parse the data represented in YAML in the provided {@code target}, producing
077   * an mapping of field names to Java object values.
078   *
079   * @param target
080   *          the YAML file to parse
081   * @return the mapping of field names to Java object values
082   * @throws IOException
083   *           if an error occurred while parsing the YAML content
084   */
085  @SuppressWarnings({ "unchecked", "null" })
086  @NonNull
087  public static Map<String, Object> parseYaml(Path target) throws IOException {
088    try (BufferedReader reader = Files.newBufferedReader(target.toAbsolutePath(), StandardCharsets.UTF_8)) {
089      return (Map<String, Object>) YAML_PARSER.load(reader);
090    }
091  }
092
093  /**
094   * Converts the provided YAML {@code map} into JSON.
095   *
096   * @param map
097   *          the YAML map
098   * @return the JSON object
099   * @throws JSONException
100   *           if an error occurred while building the JSON tree
101   */
102  public static JSONObject yamlToJson(@NonNull Map<String, Object> map) {
103    return new JSONObject(map);
104  }
105}