Display PV disconnects in the data browser

app/rtplot/src/main/java/org/csstudio/javafx/rtplot/internal/TracePainter.java

@@ -306,6 +306,10 @@
             if (Double.isNaN(value))
             {
                 flushPolyLine(gc, poly_x, poly_y, line_width);
+                if (last_y != -1) {
+                    highlightDiscontinuity(gc, x_transform, item);
+                    gc.setStroke(createStroke(line_width, line_style));
+                }
                 last_x = last_y = -1;
             }
             else
@@ -346,6 +350,10 @@
             final double value = item.getValue();
             if (Double.isNaN(value)) {
                 flushPolyLine(gc, value_poly_x, value_poly_y, line_width);
+                if (last_y != -1) {
+                    highlightDiscontinuity(gc, x_transform, item);
+                    gc.setStroke(createStroke(line_width, line_style));
+                }
             }
             else
             {
@@ -599,6 +607,20 @@
         gc.fillOval(x-size/2, y-size/2, size, size);
     }
 
+    /**
+     * Plot an additional vertical dashed line to indicate a transition to a
+     * non-plottable value, to highlight events such as an archiver disconnect.
+     * @param gc GC
+     * @param x_transform Horizontal axis
+     * @param item PlotDataItem
+     */
+    final private void highlightDiscontinuity(final Graphics2D gc, final ScreenTransform<XTYPE> x_transform,
+                                              final PlotDataItem<XTYPE> item) {
+        final int x1 = clipX(x_transform.transform(item.getPosition()));
+        gc.setStroke(createStroke(1, LineStyle.DOT));
+        gc.drawLine(x1, y_min, x1, y_max);
+    }
+
     /** Fill area. All lists will be cleared.
      *  @param gc GC
      *  @param pos Horizontal screen positions

app/trends/archive-reader/src/main/java/org/phoebus/archive/reader/appliance/ApplianceOptimizedValueIterator.java

@@ -7,13 +7,7 @@
 import org.epics.archiverappliance.retrieval.client.DataRetrieval;
 import org.epics.archiverappliance.retrieval.client.EpicsMessage;
 import org.epics.archiverappliance.retrieval.client.GenMsgIterator;
-import org.epics.vtype.Alarm;
-import org.epics.vtype.AlarmStatus;
-import org.epics.vtype.Display;
-import org.epics.vtype.Time;
-import org.epics.vtype.VNumber;
-import org.epics.vtype.VStatistics;
-import org.epics.vtype.VType;
+import org.epics.vtype.*;
 import org.phoebus.pv.TimeHelper;
 
 import edu.stanford.slac.archiverappliance.PB.EPICSEvent.PayloadInfo;
@@ -33,6 +27,8 @@
 
     private final int requestedPoints;
     private final boolean useStatistics;
+    private boolean firstDisconnnect;
+    private EpicsMessage previousMessage;
 
     /**
      * Constructor that fetches data from appliance archive reader.
@@ -55,6 +51,8 @@
         super(reader, name, start, end);
         this.requestedPoints = points;
         this.useStatistics = useStatistics;
+        this.firstDisconnnect = false;
+        this.previousMessage = null;
         this.display = determineDisplay(reader, name, end);
         fetchData();
     }
@@ -130,7 +128,22 @@
             if (closed) {
                 return null;
             }
-            message = mainIterator.next();
+            if (!reuseMessage)
+                message = mainIterator.next();
+            else {
+                message = savedMessage;
+                reuseMessage = false;
+            }
+
+            // Check if a disconnect event was recorded and return a special
+            // value if so.
+            VType check = checkDisconnect(message);
+            if (check != null)
+                return check;
+
+            savedMessage = null;
+            firstDisconnnect = false;
+            previousMessage = message;
         }
         PayloadType type = mainStream.getPayLoadInfo().getType();
         if (type == PayloadType.WAVEFORM_DOUBLE) {
@@ -159,4 +172,43 @@
             return super.extractData(message);
         }
     }
+
+    /**
+     * Method to check the EpicsMessage for fieldValues containing the
+     * 'cnxlostepsecs' and 'cnxregainedepsecs' signifying a disconnect and reconnect
+     * of the PV (for raw data) or 'connectionChange' (for optimized data).
+     * Method extracts the time of the disconnect and returns an
+     * ArchiveVString with the value 'Disconnect'
+     *
+     * @param message Current EpicsMessage to check
+     * @return a VType that can be inserted to indicate a disconnect
+     */
+    @Override
+    VType checkDisconnect(EpicsMessage message) {
+        // Call parent method to test for "cnxlostepsecs" field in case of raw data
+        VType check = super.checkDisconnect(message);
+        if (check != null)
+            return check;
+
+        // In the OptimizedWithLastSample PP we get a connectionChange and then the following bins
+        //  will have 0 events (count) in them.
+        Boolean disconnectCondition = Boolean.parseBoolean(message.getFieldValues().get("connectionChange"))
+                && message.getNumberAt(4).intValue() == 0;
+        // In the Optimized PP we get a connectionChange but the following bins (which
+        //  technically have no events) will be a repeat of the last bin to have
+        //  events. Cannot currently detect disconnect times in the Optimized
+        //  request so disconnectCondition will always evaluate as false.
+
+        if (disconnectCondition && savedMessage == null) {
+            if (!firstDisconnnect) {
+                firstDisconnnect = true;
+                return VString.of("Disconnect in bin", Alarm.disconnected(),
+                        Time.of(TimestampHelper.fromSQLTimestamp(message.getTimestamp())));
+            } else {
+                return VString.of("", Alarm.disconnected(),
+                        Time.of(TimestampHelper.fromSQLTimestamp(message.getTimestamp())));
+            }
+        }
+        return null;
+    }
 }

app/trends/archive-reader/src/main/java/org/phoebus/archive/reader/appliance/ApplianceValueIterator.java

@@ -2,14 +2,9 @@
 
 import java.io.IOException;
 import java.time.Instant;
-import java.util.ArrayList;
+import java.util.*;
 import java.util.logging.Level;
 import java.util.logging.Logger;
-import java.util.Iterator;
-import java.util.List;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Comparator;
 
 import org.epics.archiverappliance.retrieval.client.DataRetrieval;
 import org.epics.archiverappliance.retrieval.client.EpicsMessage;
@@ -72,6 +67,10 @@
 
     private final Object lock = new Object();
 
+    protected EpicsMessage savedMessage;
+    protected boolean reuseMessage;
+
+
     /**
      * Constructs a new ApplianceValueIterator.
      *
@@ -85,6 +84,8 @@
         this.name = name;
         this.start = start;
         this.end = end;
+        this.reuseMessage = false;
+        this.savedMessage = null;
     }
 
     /**
@@ -130,6 +131,10 @@
     public boolean hasNext() {
         if (closed || mainIterator == null)
             return false;
+        else if (reuseMessage)
+            // Disconnect is at the end of the iterator so
+            // still need to iterate one last time
+            return true;
         return mainIterator.hasNext();
     }
 
@@ -144,7 +149,17 @@
         synchronized (this) {
             if (closed)
                 return null;
-            message = mainIterator.next();
+            if (!reuseMessage)
+                message = mainIterator.next();
+            else {
+                message = savedMessage;
+                reuseMessage = false;
+            }
+
+            VType check = checkDisconnect(message);
+            if (check != null)
+                return check;
+            savedMessage = null;
         }
         return extractData(message);
     }
@@ -232,6 +247,29 @@
         throw new UnsupportedOperationException("PV type " + type + " is not supported.");
     }
 
+    /**
+     * Method to check the EpicsMessage for fieldValues containing the
+     * 'cnxlostepsecs' and 'cnxregainedepsecs' signifying a disconnect and reconnect
+     * of the PV. Method extracts the time of the disconnect and returns an
+     * ArchiveVString with the value 'Disconnect'
+     *
+     * @param message Current EpicsMessage to check
+     * @return a VType that can be inserted to indicate a disconnect
+     */
+    VType checkDisconnect(EpicsMessage message) {
+        Set<String> messageKeys = message.getFieldValues().keySet();
+        Boolean disconnectCondition = messageKeys.contains("cnxlostepsecs")
+                && messageKeys.contains("cnxregainedepsecs")
+                && !messageKeys.contains("startup");
+        if (disconnectCondition && savedMessage == null) {
+            long lostT = Long.parseLong(message.getFieldValues().get("cnxlostepsecs"));
+            reuseMessage = true;
+            savedMessage = message;
+            return VString.of("Disconnect", Alarm.disconnected(), Time.of(Instant.ofEpochSecond(lostT)));
+        }
+        return null;
+    }
+
     /**
      * Extracts the descriptor for the value field so it can be reused on each iteration.
      *
@@ -307,7 +345,7 @@
     }
 
     /**
-     * Extract the labels from the given payloadinfo when processing Enum Values. 
+     * Extract the labels from the given payloadinfo when processing Enum Values.
      * EnumLabels list empty if payloadinfo from request without "fetchLatestMetadata" set to true
      *
      * @param info the info to extract the labels