frontend: fix broken directory qos reporting

Motivation:

The frontend can report back to a client which QoS a file will recieve
when uploaded into a specific directory.  This calculation is wrong.

Modification:

Update the frontend to use the actual policy class that the pool
(likely) uses, when calculating the QoS of a directory.

(Unfortunately, there is insufficient information to determine exactly
with which policy a file will be written; therefore, the output may
deviate from reality if a new file is accepted by a volatile pool (one
that has lsf mode precious).  That said, this patch provides a much
better description.)

Update the hard-coded metadata to include the new file QoS (volatile)
and the new directory QoS (disk+tape and volatile).

Result:

Frontend now more accurately describes the QoS of directories; i.e., the
QoS that newly written files will recieve when written into this
directory, assuming none of the targeted pools are volatile.

Target: master
Request: 4.2
Request: 4.1
Request: 4.0
Request: 3.2
Patch: https://rb.dcache.org/r/11165
Acked-by: Albert Rossi

modules/dcache-frontend/src/main/java/org/dcache/restful/qos/QosManagement.java

@@ -21,6 +21,7 @@
 import javax.ws.rs.core.MediaType;
 
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 import diskCacheV111.util.CacheException;
@@ -40,6 +41,7 @@ public class QosManagement {
     public static final String DISK = "disk";
     public static final String TAPE = "tape";
     public static final String DISK_TAPE = "disk+tape";
+    public static final String VOLATILE = "volatile";
     public static final String UNAVAILABLE = "unavailable";
 
     public static List<String> cdmi_geographic_placement_provided = Arrays.asList("DE");
@@ -70,21 +72,15 @@ public String getQosList(@ApiParam(value = "The kind of object to query.",
 
             // query the lis of available QoS for file objects
             if ("file".equals(qosValue)) {
-
-                JSONArray list = new JSONArray(Arrays.asList(DISK, TAPE, DISK_TAPE));
+                JSONArray list = new JSONArray(Arrays.asList(DISK, TAPE, DISK_TAPE, VOLATILE));
                 json.put("name", list);
-
             }
             // query the lis of available QoS for directory objects
             else if ("directory".equals(qosValue.trim())) {
-
-                JSONArray list = new JSONArray(Arrays.asList(DISK, TAPE));
+                JSONArray list = new JSONArray(Arrays.asList(DISK, TAPE, DISK_TAPE, VOLATILE));
                 json.put("name", list);
-
-
             } else {
                 throw new NotFoundException();
-
             }
 
             json.put("status", "200");
@@ -150,6 +146,10 @@ else if (DISK_TAPE.equals(qosValue)) {
                 setBackendCapability(backendCapability, DISK_TAPE, Arrays.asList(TAPE), qoSMetadata);
 
             }
+            else if (VOLATILE.equals(qosValue)) {
+                QoSMetadata qoSMetadata = new QoSMetadata("0", cdmi_geographic_placement_provided, "100");
+                setBackendCapability(backendCapability, VOLATILE, Arrays.asList(DISK), qoSMetadata);
+            }
             // The QoS is not known or supported.
             else {
                 throw new NotFoundException();
@@ -210,6 +210,15 @@ else if (TAPE.equals(qosValue)) {
                 QoSMetadata qoSMetadata = new QoSMetadata("1", cdmi_geographic_placement_provided, "600000");
                 setBackendCapability(backendCapability, TAPE, Arrays.asList(DISK), qoSMetadata);
             }
+            // Set data and metadata for "Disk & TAPE" QoS
+            else if (DISK_TAPE.equals(qosValue)) {
+                QoSMetadata qoSMetadata = new QoSMetadata("2", cdmi_geographic_placement_provided, "100");
+                setBackendCapability(backendCapability, DISK_TAPE, Collections.emptyList(), qoSMetadata);
+            }
+            else if (VOLATILE.equals(qosValue)) {
+                QoSMetadata qoSMetadata = new QoSMetadata("0", cdmi_geographic_placement_provided, "100");
+                setBackendCapability(backendCapability, VOLATILE, Collections.emptyList(), qoSMetadata);
+            }
             // The QoS is not known or supported.
             else {
                 throw new NotFoundException();

modules/dcache-frontend/src/main/java/org/dcache/restful/util/namespace/NamespaceUtils.java

@@ -3,7 +3,6 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.InternalServerErrorException;
 
-import diskCacheV111.util.AccessLatency;
 import diskCacheV111.util.CacheException;
 import diskCacheV111.util.FileLocality;
 import diskCacheV111.util.RetentionPolicy;
@@ -16,6 +15,10 @@
 import org.dcache.namespace.FileAttribute;
 import org.dcache.namespace.FileType;
 import org.dcache.pinmanager.PinManagerCountPinsMessage;
+import org.dcache.pool.classic.ALRPReplicaStatePolicy;
+import org.dcache.pool.classic.ReplicaStatePolicy;
+import org.dcache.pool.repository.ReplicaState;
+import org.dcache.pool.repository.StickyRecord;
 import org.dcache.poolmanager.PoolMonitor;
 import org.dcache.restful.providers.JsonFileAttributes;
 import org.dcache.restful.qos.QosManagement;
@@ -26,6 +29,19 @@
  *    information.</p>
  */
 public final class NamespaceUtils {
+
+    /*
+     * FIXME Here the code is assuming the pluggable behaviour of whichever
+     * pool a new file lands on.  Currently, pools have a hard-code policy
+     * factory (LFSReplicaStatePolicyFactory), which yields two possibilities:
+     * VolatileReplicaStatePolicy if lsf is "volatile" or "transient", or
+     * ALRPReplicaStatePolicy otherwise.
+     *
+     * In the following statement, we assume files always land on non-volatile
+     * pools.
+     */
+    private static final ReplicaStatePolicy POOL_POLICY = new ALRPReplicaStatePolicy();
+
     /**
      * <p>Add quality-of-service attributes (pinned, locality, etc.) </p>
      *
@@ -74,14 +90,7 @@ public static void addQoSAttributes(JsonFileAttributes json,
                 break;
 
             case NONE: // NONE implies the target is a directory.
-                if (attributes.isDefined(FileAttribute.ACCESS_LATENCY)) {
-                    json.setCurrentQos(attributes.getAccessLatency()
-                                                       == AccessLatency.ONLINE ?
-                                                       QosManagement.DISK :
-                                                       QosManagement.TAPE);
-                } else {
-                    json.setCurrentQos(QosManagement.UNAVAILABLE);
-                }
+                json.setCurrentQos(directoryQoS(attributes));
                 break;
 
             case UNAVAILABLE:
@@ -97,6 +106,18 @@ public static void addQoSAttributes(JsonFileAttributes json,
         }
     }
 
+    private static String directoryQoS(FileAttributes attributes)
+    {
+        ReplicaState state = POOL_POLICY.getTargetState(attributes);
+        boolean isSticky = POOL_POLICY.getStickyRecords(attributes).stream()
+                .anyMatch(StickyRecord::isNonExpiring);
+        if (state == ReplicaState.PRECIOUS) {
+            return isSticky ? QosManagement.DISK_TAPE : QosManagement.TAPE;
+        } else {
+            return isSticky ? QosManagement.DISK : QosManagement.VOLATILE;
+        }
+    }
+
     /**
      * <p>Map returned attributes to JsonFileAttributes object.</p>
      *

modules/dcache/src/main/java/org/dcache/pool/repository/StickyRecord.java

@@ -30,7 +30,7 @@ public boolean isValidAt(long time)
 		return isNonExpiring() || _expire > time;
 	}
 
-	private boolean isNonExpiring()
+	public boolean isNonExpiring()
 	{
 	    return _expire == NON_EXPIRING;
 	}