Java tutorial
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Anyone downloading information from this server is obligated to secure any necessary Government licenses before exporting documents or software obtained from this server. */ package diskCacheV111.srm; import com.google.common.hash.Hashing; import eu.emi.security.authn.x509.X509Credential; import org.apache.curator.framework.CuratorFramework; import org.apache.curator.framework.recipes.nodes.PersistentNode; import org.apache.curator.utils.CloseableUtils; import org.apache.curator.utils.ZKPaths; import org.apache.zookeeper.CreateMode; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Required; import javax.security.auth.Subject; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.security.KeyStoreException; import java.security.cert.CertPath; import java.security.cert.CertificateEncodingException; import java.util.Objects; import diskCacheV111.srm.dcache.DcacheUserManager; import dmg.cells.nucleus.CellAddressCore; import dmg.cells.nucleus.CellIdentityAware; import dmg.cells.nucleus.CellLifeCycleAware; import dmg.cells.nucleus.CellMessageReceiver; import org.dcache.auth.FQAN; import org.dcache.auth.LoginReply; import org.dcache.auth.Subjects; import org.dcache.cells.CuratorFrameworkAware; import org.dcache.srm.AbstractStorageElement; import org.dcache.srm.SRM; import org.dcache.srm.SrmRequest; import org.dcache.srm.SrmResponse; import org.dcache.srm.SRMException; import org.dcache.srm.SRMInternalErrorException; import org.dcache.srm.SRMNotSupportedException; import org.dcache.srm.SRMUser; import org.dcache.srm.handler.CredentialAwareHandler; import org.dcache.srm.request.RequestCredential; import org.dcache.srm.request.RequestCredentialStorage; import static com.google.common.collect.Iterables.getFirst; import static java.nio.charset.StandardCharsets.US_ASCII; /** * SRM 2.2 backend message processor. * * Receives requests from SRM frontends. */ public class SrmService implements CellMessageReceiver, CuratorFrameworkAware, CellIdentityAware, CellLifeCycleAware { private static final Logger LOGGER = LoggerFactory.getLogger(SrmService.class); private SRM srm; private AbstractStorageElement storage; private RequestCredentialStorage requestCredentialStorage; private DcacheUserManager userManager; private CuratorFramework client; private PersistentNode node; private CellAddressCore address; private String id; @Override public void setCuratorFramework(CuratorFramework client) { this.client = client; } @Override public void setCellAddress(CellAddressCore address) { this.address = address; this.id = Hashing.murmur3_32().hashString(address.toString(), US_ASCII).toString(); } @Required public void setStorage(AbstractStorageElement storage) { this.storage = storage; } @Required public void setSrm(SRM srm) { this.srm = srm; } @Required public void setRequestCredentialStorage(RequestCredentialStorage requestCredentialStorage) { this.requestCredentialStorage = requestCredentialStorage; } @Required public void setUserManager(DcacheUserManager userManager) { this.userManager = userManager; } @Override public void afterStart() { String path = getZooKeeperBackendPath(this.id); byte[] data = address.toString().getBytes(US_ASCII); node = new PersistentNode(client, CreateMode.EPHEMERAL, false, path, data); node.start(); } @Override public void beforeStop() { if (node != null) { CloseableUtils.closeQuietly(node); } } public SrmResponse messageArrived(SrmRequest request) throws SRMException { try { CertPath certPath = getFirst(request.getSubject().getPublicCredentials(CertPath.class), null); LoginReply login = new LoginReply(request.getSubject(), request.getLoginAttributes()); SRMUser user = userManager.persist(certPath, login); String requestName = request.getRequestName(); Class<?> requestClass = request.getRequest().getClass(); String capitalizedRequestName = Character.toUpperCase(requestName.charAt(0)) + requestName.substring(1); LOGGER.debug("About to call {} handler", requestName); Constructor<?> handlerConstructor; Object handler; Method handleGetResponseMethod; try { Class<?> handlerClass = Class.forName("org.dcache.srm.handler." + capitalizedRequestName); handlerConstructor = handlerClass.getConstructor(SRMUser.class, requestClass, AbstractStorageElement.class, SRM.class, String.class); handler = handlerConstructor.newInstance(user, request.getRequest(), storage, srm, request.getRemoteHost()); if (handler instanceof CredentialAwareHandler) { CredentialAwareHandler credentialAware = (CredentialAwareHandler) handler; RequestCredential requestCredential = saveRequestCredential(request.getSubject(), request.getCredential()); credentialAware.setCredential(requestCredential); } handleGetResponseMethod = handlerClass.getMethod("getResponse"); } catch (ClassNotFoundException e) { if (LOGGER.isDebugEnabled()) { LOGGER.info("handler discovery and dynamic loading failed", e); } else { LOGGER.info("handler discovery and dynamic loading failed"); } throw new SRMNotSupportedException(requestName + " is unsupported"); } Object result = handleGetResponseMethod.invoke(handler); return new SrmResponse(id, result); } catch (CertificateEncodingException | KeyStoreException e) { throw new SRMInternalErrorException("Failed to process certificate chain.", e); } catch (InvocationTargetException | NoSuchMethodException | InstantiationException | IllegalAccessException | RuntimeException e) { LOGGER.error("Please report this failure to support@dcache.org", e); throw new SRMInternalErrorException("Internal error (server log contains additional information)"); } } private RequestCredential saveRequestCredential(Subject subject, X509Credential credential) { String dn = Subjects.getDn(subject); FQAN fqan = Subjects.getPrimaryFqan(subject); RequestCredential requestCredential = RequestCredential.newRequestCredential(dn, Objects.toString(fqan, null), requestCredentialStorage); requestCredential.keepBestDelegatedCredential(credential); requestCredential.saveCredential(); return requestCredential; } public static String getZooKeeperBackendPath(String id) { return ZKPaths.makePath("/dcache/srm/backends", id); } }