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DataHub Auth API for developers to write custom Authentication & Authorization plugins for DataHub

There is a newer version: 0.14.1-12rc1

package com.datahub.authorization;

import java.util.Collections;
import java.util.Set;
import java.util.concurrent.CompletableFuture;
import java.util.function.Function;
import java.util.function.Supplier;
import lombok.Builder;
import lombok.Getter;
import lombok.RequiredArgsConstructor;
import lombok.Value;

/**
 * Helper class for lazy resolution of fields Input resolveField function that is given as input
 * will only be called when getFieldValuesFuture is called
 */
@RequiredArgsConstructor
public class FieldResolver {
  private final Supplier> resolveField;

  @Getter(lazy = true)
  private final CompletableFuture fieldValuesFuture = resolveField.get();

  private static final FieldValue EMPTY = new FieldValue(Collections.emptySet());

  /** Helper function that returns FieldResolver for precomputed values */
  public static FieldResolver getResolverFromValues(Set values) {
    return new FieldResolver(
        () -> CompletableFuture.completedFuture(FieldValue.builder().values(values).build()));
  }

  /** Helper function that returns FieldResolver given a fetchFieldValue function */
  public static FieldResolver getResolverFromFunction(
      EntitySpec entitySpec, Function fetchFieldValue) {
    return new FieldResolver(
        () -> CompletableFuture.supplyAsync(() -> fetchFieldValue.apply(entitySpec)));
  }

  public static FieldValue emptyFieldValue() {
    return EMPTY;
  }

  /**
   * Container for storing the field value, in case we need to extend this to have more types of
   * field values
   */
  @Value
  @Builder
  public static class FieldValue {
    Set values;
  }
}