ContentPathPropertyMapper.java

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 * Copyright (C) 2022 wcm.io
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 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
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 *
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 *
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 * distributed under the License is distributed on an "AS IS" BASIS,
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package io.wcm.siteapi.handler.caconfig.impl.property;

import java.util.Map;
import java.util.stream.Collectors;

import org.apache.commons.lang3.StringUtils;
import org.apache.sling.api.SlingHttpServletRequest;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.apache.sling.api.resource.ValueMap;
import org.apache.sling.api.wrappers.ValueMapDecorator;
import org.apache.sling.caconfig.spi.metadata.PropertyMetadata;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Reference;
import org.osgi.service.component.propertytypes.ServiceRanking;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.day.cq.dam.api.DamConstants;
import com.day.cq.wcm.api.NameConstants;
import com.day.cq.wcm.api.Page;

import io.wcm.handler.link.Link;
import io.wcm.handler.link.LinkHandler;
import io.wcm.handler.media.Media;
import io.wcm.handler.media.MediaArgs;
import io.wcm.handler.media.MediaComponentPropertyResolver;
import io.wcm.handler.media.MediaHandler;
import io.wcm.siteapi.handler.link.LinkDecoratorManager;
import io.wcm.siteapi.handler.media.MediaDecoratorManager;
import io.wcm.siteapi.processor.caconfig.ContextAwareConfigurationPropertyMapper;
import io.wcm.sling.commons.adapter.AdaptTo;

/**
 * Detects properties that use widgetType=pathbrowser.
 * Depending on the actual path, those are either references to content pages or assets.
 * A corresponding link or media object is resolved, and mapped to it's JSON representation.
 */
@Component(service = ContextAwareConfigurationPropertyMapper.class)
@ServiceRanking(-250)
public class ContentPathPropertyMapper implements ContextAwareConfigurationPropertyMapper<Object> {

  // copied from io.wcm.caconfig.editor.EditorProperties to avoid direct dependency
  static final String PROPERTY_WIDGET_TYPE = "widgetType";
  static final String WIDGET_TYPE_PATHBROWSER = "pathbrowser";

  private static final Logger log = LoggerFactory.getLogger(ContentPathPropertyMapper.class);

  @Reference
  private LinkDecoratorManager linkDecoratorManager;
  @Reference
  private MediaDecoratorManager mediaDecoratorManager;

  @Override
  public boolean accept(@NotNull Object value,
      @NotNull PropertyMetadata<?> metadata, @NotNull SlingHttpServletRequest request) {
    Map<String, String> properties = metadata.getProperties();
    if (properties == null) {
      return false;
    }
    return StringUtils.equals(properties.get(PROPERTY_WIDGET_TYPE), WIDGET_TYPE_PATHBROWSER);
  }

  @Override
  public @Nullable Object map(@NotNull Object value,
      @NotNull PropertyMetadata<?> metadata, @NotNull SlingHttpServletRequest request) {
    Resource resource = getResource(value, request.getResourceResolver());
    if (resource != null) {
      if (isPage(resource)) {
        return buildPageReference(resource, request);
      }
      else if (isAsset(resource)) {
        return buildMediaReference(resource, metadata, request);
      }
    }
    return null;
  }

  /**
   * Check if the given path points to a valid resource.
   */
  private @Nullable Resource getResource(@NotNull Object value, @NotNull ResourceResolver resourceResolver) {
    if (value instanceof String) {
      return resourceResolver.getResource((String)value);
    }
    else {
      return null;
    }
  }

  /**
   * Checks if the resource is a AEM page.
   */
  private boolean isPage(@NotNull Resource resource) {
    return StringUtils.equals(resource.getResourceType(), NameConstants.NT_PAGE);
  }

  /**
   * Resolves a link to the page using link handler and returns the decorated reference.
   */
  private @Nullable Object buildPageReference(@NotNull Resource resource, @NotNull SlingHttpServletRequest request) {
    Page page = resource.adaptTo(Page.class);
    if (page == null) {
      return null;
    }
    LinkHandler linkHandler = AdaptTo.notNull(request, LinkHandler.class);
    Link link = linkHandler.get(page).build();
    return linkDecoratorManager.decorate(link, request.getResource());
  }

  /**
   * Checks if the resource is an AEM asset.
   */
  private boolean isAsset(@NotNull Resource resource) {
    return StringUtils.equals(resource.getResourceType(), DamConstants.NT_DAM_ASSET);
  }

  /**
   * Resolves a reference to the asset using media handler and returns the decorated reference.
   */
  private @Nullable Object buildMediaReference(@NotNull Resource resource,
      @NotNull PropertyMetadata<?> metadata, @NotNull SlingHttpServletRequest request) {
    MediaHandler mediaHandler = AdaptTo.notNull(request, MediaHandler.class);

    // support reading media handler component properties from metadata
    MediaArgs mediaArgs = new MediaArgs();
    Map<String, String> properties = metadata.getProperties();
    if (properties != null) {
      try (MediaComponentPropertyResolver resolver = new MediaComponentPropertyResolver(convertToValueMap(properties))) {
        mediaArgs.mediaFormatOptions(resolver.getMediaFormatOptions());
        mediaArgs.autoCrop(resolver.isAutoCrop());
        mediaArgs.imageSizes(resolver.getImageSizes());
      }
      catch (Exception ex) {
        log.warn("Unable to close MediaComponentPropertyResolver.", ex);
      }
    }

    Media media = mediaHandler.get(resource.getPath(), mediaArgs).build();
    return mediaDecoratorManager.decorate(media, request.getResource());
  }

  /**
   * Converts a map of string properties to a value map.
   * Property values separates by "," are transformed into an string array.
   * @param properties Properties
   * @return Value map
   */
  private ValueMap convertToValueMap(Map<String, String> properties) {
    return new ValueMapDecorator(properties.entrySet().stream()
        .map(entry -> Map.<String, Object>entry(entry.getKey(), StringUtils.split(entry.getValue(), ",")))
        .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)));
  }

}