Class EnvConfig

java/src/org/openqa/selenium/grid/config/EnvConfig.java:33–79

Exposes environment variables as config settings by mapping "section.option" to "SECTION_OPTION". Dashes and periods in the options are converted to underscores, and all characters are upper-cased assuming a US English locale.

 * upper-cased assuming a US English locale.
 */
public class EnvConfig implements Config {

  @Override
  public Optional<List<String>> getAll(String section, String option) {
    Require.nonNull("Section name", section);
    Require.nonNull("Option name", option);

    String key =
        String.format("%s_%s", section, option)
            .toUpperCase(Locale.ENGLISH)
            .replace("-", "_")
            .replace(".", "_");

    String value = System.getenv().get(key);
    if (value == null) {
      return Optional.empty();
    }

    if (value.startsWith("$")) {
      value = System.getenv(value.substring(1));
    }

    return Optional.ofNullable(value).map(List::of);
  }

  @Override
  public Set<String> getSectionNames() {
    return System.getenv().keySet().stream()
        // We need at least two "_" characters
        .filter(key -> key.split("_").length > 1)
        .map(key -> key.substring(0, key.indexOf('_')))
        .map(key -> key.toLowerCase(Locale.ENGLISH))
        .collect(toSortedSet());
  }

  @Override
  public Set<String> getOptions(String section) {
    Require.nonNull("Section name to get options for", section);

    String prefix = String.format("%s_", section).toUpperCase(Locale.ENGLISH);
    return System.getenv().keySet().stream()
        .filter(key -> key.startsWith(prefix))
        .map(key -> key.substring(prefix.length()))
        .map(key -> key.toLowerCase(Locale.ENGLISH))
        .collect(toSortedSet());
  }
}