SCM-Manager/scm-webapp/src/main/java/sonia/scm/PushStateDispatcherProvider.java

/*
 * MIT License
 *
 * Copyright (c) 2020-present Cloudogu GmbH and Contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
    
package sonia.scm;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Strings;

import javax.inject.Inject;
import javax.inject.Provider;

/**
 * Injection Provider for the {@link PushStateDispatcher}. The provider will return a {@link ProxyPushStateDispatcher}
 * if the system property {@code PushStateDispatcherProvider#PROPERTY_TARGET} is set to a proxy target url, otherwise
 * a {@link TemplatingPushStateDispatcher} is used.
 *
 * @since 2.0.0
 */
public class PushStateDispatcherProvider implements Provider<PushStateDispatcher> {

  @VisibleForTesting
  static final String PROPERTY_TARGET = "sonia.scm.ui.proxy";

  private Provider<TemplatingPushStateDispatcher> templatingPushStateDispatcherProvider;

  @Inject
  public PushStateDispatcherProvider(Provider<TemplatingPushStateDispatcher> templatingPushStateDispatcherProvider) {
    this.templatingPushStateDispatcherProvider = templatingPushStateDispatcherProvider;
  }

  @Override
  public PushStateDispatcher get() {
    String target = System.getProperty(PROPERTY_TARGET);
    if (Strings.isNullOrEmpty(target)) {
      return templatingPushStateDispatcherProvider.get();
    }
    return new ProxyPushStateDispatcher(target);
  }
}