static Optional parse()

in sources/src/main/java/com/google/solutions/jitaccess/catalog/legacy/ProjectRole.java [192:243]
43 lines of code
8 McCabe index (conditional complexity)

    static Optional<EligibilityCondition> parse(@Nullable Expr bindingCondition) {
      if (bindingCondition == null ||
        Strings.isNullOrEmpty(bindingCondition.getExpression()) ||
        bindingCondition.getExpression().isBlank()) {
        return Optional.empty();
      }

      //
      // Break the condition into clauses and check if one the clauses
      // marks this as an eligible role.
      //
      // Any remaining clauses make up the resource condition.
      //
      var clauses = new IamCondition(bindingCondition.getExpression()).splitAnd();
      var jitEligible = clauses
        .stream()
        .anyMatch(c -> matches(c.toString(), JIT_CONDITION_PATTERN));
      var mpaEligible = clauses
        .stream()
        .anyMatch(c -> matches(c.toString(), MPA_CONDITION_PATTERN));
      var resourceConditionClauses = clauses
        .stream()
        .filter(c -> !matches(c.toString(), JIT_CONDITION_PATTERN))
        .filter(c -> !matches(c.toString(), MPA_CONDITION_PATTERN))
        .collect(Collectors.toList());

      String resourceCondition;
      try {
        resourceCondition = resourceConditionClauses.isEmpty()
          ? null
          : IamCondition.and(resourceConditionClauses).reformat().toString();
      }
      catch (IllegalArgumentException invalidCel) {
        return Optional.empty();
      }

      if (jitEligible) {
        return Optional.of(new EligibilityCondition(
          bindingCondition.getExpression(),
          ActivationType.JIT,
          resourceCondition));
      }
      else if (mpaEligible) {
        return Optional.of(new EligibilityCondition(
          bindingCondition.getExpression(),
          ActivationType.MPA,
          resourceCondition));
      }
      else {
        return Optional.empty();
      }
    }