Dynamic Media 中的视频

dependency>
     <groupId>com.day.cq.dam</groupId>
     <artifactId>cq-scene7-api</artifactId>
     <version>5.12.64</version>
     <scope>provided</scope>
</dependency>

@Component
        service = Servlet.class
)
@HttpWhiteboardServletPattern(value = ManifestServlet.SERVLET_PATTERN)
@HttpWhiteboardContextSelect(value = Constants.SERVLET_CONTEXT_SELECTOR)
public class ManifestServlet extends HttpServlet {

   private static final Logger LOGGER = LoggerFactory.getLogger(ManifestServlet.class);

   private final ObjectMapper objectMapper;

    @Reference
    private Scene7Service scene7Service;

   public static final String SERVLET_PATTERN = Constants.VIDEO_API_PREFIX + "/manifestUrl";

   public ManifestServlet() {
         this.objectMapper = new ObjectMapper();
         objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
   }

   @Override

   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
        final ResourceResolver resolver = getResourceResolver(request);
        String assetPath = request.getParameter("assetPath");
        String manifest = request.getParameter("manifestType");
        String onlyIfPublished = request.getParameter("onlyIfPublished");
        Resource resource = resolver.getResource(assetPath);
        response.setCharacterEncoding(StandardCharsets.UTF_8.toString());
        response.setContentType("application/json");
        if(resource == null) {
            LOGGER.info("could not retrieve the resource from JCR");
            error("could not retrieve the resource from JCR", response);
            return;
        }

        String manifestUri = null;

        try{
            ManifestType manifestType =  ManifestType.DASH;
            if(manifest != null) {
                manifestType = ManifestType.valueOf(manifest);
            }
            manifestUri = scene7Service.getVideoManifestURI(resource, manifestType, onlyIfPublished != null);
            objectMapper.writeValue(response.getWriter(), new ManifestUrl(manifestUri));
            response.setContentType("application/json");
        } catch (Exception e) {
            LOGGER.error(e.getMessage(), e);
            error(String.format("Unable to get the manifest url for %s. %s", assetPath, e.getMessage()), response);
        }
    }

    private ResourceResolver getResourceResolver(HttpServletRequest request) {
        Object rr = request.getAttribute(AuthenticationSupport.REQUEST_ATTRIBUTE_RESOLVER);
        if (!(rr instanceof ResourceResolver)) {
            throw new IllegalStateException(
                    "The request does not seem to have been created via Apache Sling's authentication mechanism.");
        } else {
            return (ResourceResolver) rr;
        }
    }

    private void error(String errorMessage, HttpServletResponse response) throws IOException {
        ManifestUrl errorManifest = new ManifestUrl(null);
        errorManifest.setErrorMessage(errorMessage);
        response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
        objectMapper.writeValue(response.getWriter(), errorManifest);
    }
}

public class ManifestUrl extends VideoResponse {
     String manifestUrl;
     public ManifestUrl(String manifestUrl) {
         this.manifestUrl = manifestUrl;
     }
     public String getManifestUrl() {
         return manifestUrl;
     }
}

public abstract class VideoResponse {
     String errorString;

     public String getErrorString() {
         return errorString;
     }

     public void setErrorMessage(String errorString) {
         this.errorString = errorString;
     }
}

public final class Constants {

     private Constants() {
     }

     public static final String VIDEO_API_PREFIX = "/dynamicmedia/video";
     public static final String SERVLET_CONTEXT_SELECTOR = "(" + HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_NAME + "=" +
             DMSampleApiHttpContext.CONTEXT_NAME + ")";

 }

public class DMSampleApiHttpContext extends ServletContextHelper {

 public static final String CONTEXT_NAME = "com.adobe.dmSample";
 public static final String CONTEXT_PATH = "/dmSample";

 private final MimeTypeService mimeTypeService;

 private final AuthenticationSupport authenticationSupport;

 /**
  * Constructs a new context that will use the given dependencies.
  *
  * @param mimeTypeService Used when providing mime type of requests.
  * @param authenticationSupport Used to authenticate requests with sling.
  */
 @Activate
 public DMSampleApiHttpContext(@Reference final MimeTypeService mimeTypeService,
                               @Reference final AuthenticationSupport authenticationSupport) {
     this.mimeTypeService = mimeTypeService;
     this.authenticationSupport = authenticationSupport;
 }

 // ---------- HttpContext interface ----------------------------------------
 /**
  * Returns the MIME type as resolved by the <code>MimeTypeService</code> or
  * <code>null</code> if the service is not available.
  */
 @Override
 public String getMimeType(String name) {
     MimeTypeService mtservice = mimeTypeService;
     if (mtservice != null) {
         return mtservice.getMimeType(name);
     }
     return null;
 }

 /**
  * Returns the real context path that is used to mount this context.
  * @param req servlet request
  * @return the context path
  */
 public static String getRealContextPath(HttpServletRequest req) {
     final String path = req.getContextPath();
     if (path.equals(CONTEXT_PATH)) {
         return "";
     }
     return path.substring(CONTEXT_PATH.length());
 }

 /**
  * Returns a request wrapper that transforms the context path back to the original one
  * @param req request
  * @return the request wrapper
  */
 public static HttpServletRequest createContextPathAdapterRequest(HttpServletRequest req) {
     return new HttpServletRequestWrapper(req) {

         @Override
         public String getContextPath() {
             return getRealContextPath((HttpServletRequest) getRequest());
         }

     };

 }

 /**
  * Always returns <code>null</code> because resources are all provided
  * through individual endpoint implementations.
  */
 @Override
 public URL getResource(String name) {
     return null;
 }

 /**
  * Tries to authenticate the request using the
  * <code>SlingAuthenticator</code>. If the authenticator or the Repository
  * is missing this method returns <code>false</code> and sends a 503/SERVICE
  * UNAVAILABLE status back to the client.
  */
 @Override
 public boolean handleSecurity(HttpServletRequest request,
                               HttpServletResponse response) throws IOException {

     final AuthenticationSupport authenticator = this.authenticationSupport;
     if (authenticator != null) {
         return authenticator.handleSecurity(createContextPathAdapterRequest(request), response);
     }

     // send 503/SERVICE UNAVAILABLE, flush to ensure delivery
     response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE,
             "AuthenticationSupport service missing. Cannot authenticate request.");
     response.flushBuffer();

     // terminate this request now
     return false;
 }
}