HealthOutcome.java

package com.retailsvc.http;

import java.util.List;
import java.util.Objects;

/**
 * Carrier for the {@link Handlers#healthHandler health handler} response.
 *
 * <p>Overall health is derived from {@link #dependencies()}: an empty list reports as {@code "Up"};
 * otherwise the outcome is {@code "Up"} only when every dependency is up. Callers describe their
 * dependencies and the library aggregates.
 *
 * @param dependencies per-dependency statuses; {@code null} is normalised to an empty list
 */
public record HealthOutcome(List<Dependency> dependencies) {

  public HealthOutcome {
    dependencies = List.copyOf(Objects.requireNonNullElse(dependencies, List.of()));
  }

  /** {@code true} when every dependency is up (vacuously true for an empty list). */
  public boolean up() {
    return dependencies.stream().allMatch(Dependency::up);
  }
}