server: Add bar chart data provider with /bars endpoint

This commit uses the newly introduced data provider type
to support "bar chart" views. It focuses on implementing
the /bars endpoint, which will be the second endpoint
invoked by viewer.

[Added] /bars endpoint for bar chart view

Author: Siwei Zhang

trace-server/org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests/src/org/eclipse/tracecompass/incubator/trace/server/jersey/rest/core/tests/services/BarChartDataProviderServiceTest.java

@@ -17,11 +17,13 @@
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import javax.ws.rs.client.Entity;
 import javax.ws.rs.client.WebTarget;
@@ -32,10 +34,15 @@
 import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.AxisDomainStub;
 import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.EntryStub;
 import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.ExperimentModelStub;
+import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.SamplingStub;
 import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.TmfTreeModelWithAxisDescriptorsResponseStub;
 import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.TmfTreeModelWithAxisDescriptorsStub;
 import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.TmfXYAxisDescriptionStub;
+import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.XyModelStub;
+import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.XyOutputResponseStub;
+import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs.XySeriesStub;
 import org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.utils.RestServerTest;
+import org.eclipse.tracecompass.tmf.core.model.StyleProperties;
 import org.junit.Test;
 
 /**
@@ -47,7 +54,11 @@
 public class BarChartDataProviderServiceTest extends RestServerTest {
     private static final String DATA_PROVIDER_RESPONSE_FAILED_MSG = "There should be a positive response for the data provider";
     private static final String MODEL_NULL_MSG = "The model is null, maybe the analysis did not run long enough?";
+    private static final String REQUESTED_ITEMS_KEY = "requested_items";
+    private static final String REQUESTED_SAMPLING_KEY = "requested_sampling";
     private static final int MAX_ITER = 40;
+    private static final long TRACE_START_TIME = 1450193697034689597L;
+    private static final long TRACE_END_TIME = 1450193745774189602L;
     private static final List<EntryStub> EXPECTED_ENTRIES = List.of(
             new EntryStub(Arrays.asList("ust"), 0, -1, true, null),
             new EntryStub(Arrays.asList("UNKNOWN_PID"), 1, 0, true, null));
@@ -99,6 +110,30 @@ public void testBarChartDataProvider() throws InterruptedException {
         assertNotNull("Y axis description should not be null", yAxis);
         List<EntryStub> entries = model.getEntries();
         assertFalse(entries.isEmpty());
+
+        // Test getting the bars endpoint with descriptors for bar chart
+        WebTarget barsEnpoint = getBarChartBarsEndpoint(exp.getUUID().toString(), CALL_STACK_BAR_CHART_DATAPROVIDER_ID);
+        parameters = new HashMap<>();
+        List<Integer> items = new ArrayList<>();
+        for (EntryStub entry : entries) {
+            items.add(entry.getId());
+        }
+        parameters.put(REQUESTED_ITEMS_KEY, items);
+        parameters.put(REQUESTED_TIMES_KEY, List.of(TRACE_START_TIME, TRACE_END_TIME));
+        List<List<Number>> ranges = new ArrayList<>();
+        ranges.add(List.of(1L, 100L));
+        ranges.add(List.of(101L, 10000L));
+        ranges.add(List.of(10001L, 1000000L));
+        parameters.put(REQUESTED_SAMPLING_KEY, ranges);
+        try (Response series = barsEnpoint.request().post(Entity.json(new QueryParameters(parameters, Collections.emptyList())))) {
+            assertEquals(DATA_PROVIDER_RESPONSE_FAILED_MSG, 200, series.getStatus());
+            XyOutputResponseStub xyModelResponse = series.readEntity(XyOutputResponseStub.class);
+            assertNotNull(xyModelResponse);
+
+            XyModelStub xyModel = xyModelResponse.getModel();
+            Set<XySeriesStub> xySeries = xyModel.getSeries();
+            assertFalse(xySeries.isEmpty());
+        }
     }
 
     /**
@@ -185,5 +220,66 @@ public void testCallStackBarChartDataProvider() throws InterruptedException {
             assertEquals("Labels mismatch at index " + i, expected.getLabels(), actual.getLabels());
             assertEquals("Style mismatch at index " + i, expected.getStyle(), actual.getStyle());
         }
+
+        /*
+         * Test the data in bars end point.
+         */
+        WebTarget barsEnpoint = getBarChartBarsEndpoint(exp.getUUID().toString(), CALL_STACK_BAR_CHART_DATAPROVIDER_ID);
+        parameters = new HashMap<>();
+        List<Integer> items = new ArrayList<>();
+        for (EntryStub entry : actualEntries) {
+            items.add(entry.getId());
+        }
+        parameters.put(REQUESTED_ITEMS_KEY, items);
+        List<List<Number>> ranges = List.of(
+                List.of(1L, 100L),
+                List.of(101L, 10_000L),
+                List.of(10_001L, 1_000_000L),
+                List.of(1_000_001L, 1_000_000_000L),
+                List.of(1_000_000_001L, 1_000_000_000_000L)
+        );
+        parameters.put(REQUESTED_SAMPLING_KEY, ranges);
+        parameters.put(REQUESTED_TIMES_KEY, List.of(TRACE_START_TIME, TRACE_END_TIME));
+        XyOutputResponseStub xyModelResponse;
+        try (Response series = barsEnpoint.request().post(Entity.json(new QueryParameters(parameters, Collections.emptyList())))) {
+            assertEquals(DATA_PROVIDER_RESPONSE_FAILED_MSG, 200, series.getStatus());
+            xyModelResponse = series.readEntity(XyOutputResponseStub.class);
+        }
+        assertNotNull(xyModelResponse);
+        XyModelStub xyModel = xyModelResponse.getModel();
+        Set<XySeriesStub> xySeries = xyModel.getSeries();
+        assertEquals("Number of series mismatch", 1, xySeries.size());
+        XySeriesStub seriesStub = xySeries.iterator().next();
+
+        // Validate fields
+        assertEquals("Name mismatch", "UNKNOWN_PID", seriesStub.getName());
+        assertEquals("ID mismatch", 1, seriesStub.getId());
+        List<Double> actualYValues = seriesStub.getYValues();
+        List<Double> expectedYValues = Arrays.asList(1.0, 0.0, 1764.0, 178.0, 5.0);
+        assertEquals("Y values size mismatch", expectedYValues.size(), actualYValues.size());
+        for (int i = 0; i < expectedYValues.size(); i++) {
+            assertEquals("Y value mismatch at index " + i, expectedYValues.get(i), actualYValues.get(i), 0.000001);
+        }
+
+        // Validate xValues
+        SamplingStub xValues = seriesStub.getXValues();
+        assertTrue("xValues should be a RangesStub", xValues instanceof SamplingStub.RangesStub);
+        List<SamplingStub.RangesStub.RangeStub> actualRanges = ((SamplingStub.RangesStub) xValues).getRanges();
+        List<SamplingStub.RangesStub.RangeStub> expectedRanges = Arrays.asList(
+                new SamplingStub.RangesStub.RangeStub(1L, 100L),
+                new SamplingStub.RangesStub.RangeStub(101L, 10_000L),
+                new SamplingStub.RangesStub.RangeStub(10_001L, 1_000_000L),
+                new SamplingStub.RangesStub.RangeStub(1_000_001L, 1_000_000_000L),
+                new SamplingStub.RangesStub.RangeStub(1_000_000_001L, 1_000_000_000_000L)
+        );
+        assertEquals("Range size mismatch", expectedRanges.size(), actualRanges.size());
+        for (int i = 0; i < expectedRanges.size(); i++) {
+            assertEquals("Range mismatch at index " + i, expectedRanges.get(i), actualRanges.get(i));
+        }
+
+        // Validate style
+        assertNotNull("Style should not be null", seriesStub.getStyle());
+        assertEquals("Series type should be bar", "bar",
+                seriesStub.getStyle().getStyleValues().get(StyleProperties.SERIES_TYPE));
     }
 }

trace-server/org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests/src/org/eclipse/tracecompass/incubator/trace/server/jersey/rest/core/tests/stubs/AxisDomainStub.java

@@ -23,7 +23,7 @@
 
 /**
  * A stub class for AxisDomain which can be either Categorical or TimeRange.
- * Matches the trace server protocol schema for AxisDomain.
+ * Matches the trace server protocol schema for <code>AxisDomain</code>.
  *
  * @author Siwei Zhang
  */

trace-server/org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests/src/org/eclipse/tracecompass/incubator/trace/server/jersey/rest/core/tests/stubs/SamplingStub.java

@@ -0,0 +1,195 @@
+/**********************************************************************
+ * Copyright (c) 2025 Ericsson
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License 2.0 which
+ * accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ **********************************************************************/
+package org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core.tests.stubs;
+
+import java.io.Serializable;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+
+import org.eclipse.jdt.annotation.Nullable;
+
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import org.eclipse.tracecompass.tmf.core.model.barchart.Sampling;
+
+/**
+ * Stub version of {@link Sampling}.
+ *
+ * @author Siwei Zhang
+ */
+@JsonSerialize(using = SamplingStubSerializer.class)
+@JsonDeserialize(using = SamplingStubDeserializer.class)
+public sealed interface SamplingStub extends Serializable permits
+        SamplingStub.TimestampsStub,
+        SamplingStub.CategoriesStub,
+        SamplingStub.RangesStub {
+
+    /**
+     * Get the number of sampling points
+     *
+     * @return number of points
+     */
+    int size();
+
+    /**
+     * Timestamp-based sampling.
+     */
+    final class TimestampsStub implements SamplingStub {
+        private static final long serialVersionUID = -8242136490356720296L;
+
+        private final long[] fTimestamps;
+
+        public TimestampsStub(long[] timestamps) {
+            this.fTimestamps = Objects.requireNonNull(timestamps);
+        }
+
+        public long[] getTimestamps() {
+            return fTimestamps;
+        }
+
+        @Override
+        public int size() {
+            return fTimestamps.length;
+        }
+
+        @Override
+        public boolean equals(@Nullable Object obj) {
+            return (this == obj) || (obj instanceof TimestampsStub other &&
+                    Arrays.equals(this.fTimestamps, other.fTimestamps));
+        }
+
+        @Override
+        public int hashCode() {
+            return Arrays.hashCode(fTimestamps);
+        }
+
+        @Override
+        public String toString() {
+            return "Timestamps" + Arrays.toString(fTimestamps); //$NON-NLS-1$
+        }
+    }
+
+    /**
+     * Categorical sampling (e.g., names).
+     */
+    final class CategoriesStub implements SamplingStub {
+        private static final long serialVersionUID = 3751152643508688051L;
+
+        private final List<String> fCategories;
+
+        public CategoriesStub(List<String> categories) {
+            this.fCategories = Objects.requireNonNull(categories);
+        }
+
+        public List<String> getCategories() {
+            return fCategories;
+        }
+
+        @Override
+        public int size() {
+            return fCategories.size();
+        }
+
+        @Override
+        public boolean equals(@Nullable Object obj) {
+            return (this == obj) || (obj instanceof CategoriesStub other &&
+                    Objects.equals(this.fCategories, other.fCategories));
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(fCategories);
+        }
+
+        @Override
+        public String toString() {
+            return "Categories" + fCategories.toString(); //$NON-NLS-1$
+        }
+    }
+
+    /**
+     * Range sampling, representing start-end pairs.
+     */
+    final class RangesStub implements SamplingStub {
+        private static final long serialVersionUID = 3434126540189939098L;
+
+        private final List<RangeStub> fRanges;
+
+        public RangesStub(List<RangeStub> ranges) {
+            this.fRanges = Objects.requireNonNull(ranges);
+        }
+
+        public List<RangeStub> getRanges() {
+            return fRanges;
+        }
+
+        @Override
+        public int size() {
+            return fRanges.size();
+        }
+
+        @Override
+        public boolean equals(@Nullable Object obj) {
+            return (this == obj) || (obj instanceof RangesStub other &&
+                    Objects.equals(this.fRanges, other.fRanges));
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(fRanges);
+        }
+
+        @Override
+        public String toString() {
+            return "Ranges" + fRanges.toString(); //$NON-NLS-1$
+        }
+
+        /**
+         * Stub representing a range.
+         */
+        public static final class RangeStub implements Serializable {
+            private static final long serialVersionUID = 1L;
+
+            private final long fStart;
+            private final long fEnd;
+
+            public RangeStub(long start, long end) {
+                this.fStart = start;
+                this.fEnd = end;
+            }
+
+            public long getStart() {
+                return fStart;
+            }
+
+            public long getEnd() {
+                return fEnd;
+            }
+
+            @Override
+            public boolean equals(@Nullable Object obj) {
+                return (this == obj) || (obj instanceof RangeStub other &&
+                        fStart == other.fStart && fEnd == other.fEnd);
+            }
+
+            @Override
+            public int hashCode() {
+                return Objects.hash(fStart, fEnd);
+            }
+
+            @Override
+            public String toString() {
+                return "[" + fStart + ", " + fEnd + "]"; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
+            }
+        }
+    }
+}