feat(trace/api): Add support for projecting tables

This change adds support for projecting certain columns of a table. This
enables faster reading for tables with high number of columns.
Currently, we support projection in the Parquet-based workload formats.
Other formats are text-based and will probably not benefit much from
projection.

2 files changed, 4 insertions, 4 deletions

diff --git a/opendc-trace/opendc-trace-gwf/src/main/kotlin/org/opendc/trace/gwf/GwfTraceFormat.kt b/opendc-trace/opendc-trace-gwf/src/main/kotlin/org/opendc/trace/gwf/GwfTraceFormat.kt
index 63688523..8d9eab82 100644
--- a/opendc-trace/opendc-trace-gwf/src/main/kotlin/org/opendc/trace/gwf/GwfTraceFormat.kt
+++ b/opendc-trace/opendc-trace-gwf/src/main/kotlin/org/opendc/trace/gwf/GwfTraceFormat.kt
@@ -70,7 +70,7 @@ public class GwfTraceFormat : TraceFormat {
         }
     }
 
-    override fun newReader(path: Path, table: String): TableReader {
+    override fun newReader(path: Path, table: String, projection: List<TableColumn<*>>?): TableReader {
         return when (table) {
             TABLE_TASKS -> GwfTaskTableReader(factory.createParser(path.toFile()))
             else -> throw IllegalArgumentException("Table $table not supported")
diff --git a/opendc-trace/opendc-trace-gwf/src/test/kotlin/org/opendc/trace/gwf/GwfTraceFormatTest.kt b/opendc-trace/opendc-trace-gwf/src/test/kotlin/org/opendc/trace/gwf/GwfTraceFormatTest.kt
index 9bf28ad7..411d45d0 100644
--- a/opendc-trace/opendc-trace-gwf/src/test/kotlin/org/opendc/trace/gwf/GwfTraceFormatTest.kt
+++ b/opendc-trace/opendc-trace-gwf/src/test/kotlin/org/opendc/trace/gwf/GwfTraceFormatTest.kt
@@ -58,7 +58,7 @@ internal class GwfTraceFormatTest {
     @Test
     fun testTableReader() {
         val path = Paths.get(checkNotNull(GwfTraceFormatTest::class.java.getResource("/trace.gwf")).toURI())
-        val reader = format.newReader(path, TABLE_TASKS)
+        val reader = format.newReader(path, TABLE_TASKS, null)
 
         assertAll(
             { assertTrue(reader.nextRow()) },
@@ -73,7 +73,7 @@ internal class GwfTraceFormatTest {
     @Test
     fun testReadingRowWithDependencies() {
         val path = Paths.get(checkNotNull(GwfTraceFormatTest::class.java.getResource("/trace.gwf")).toURI())
-        val reader = format.newReader(path, TABLE_TASKS)
+        val reader = format.newReader(path, TABLE_TASKS, null)
 
         // Move to row 7
         for (x in 1..6)
@@ -85,7 +85,7 @@ internal class GwfTraceFormatTest {
             { assertEquals("7", reader.get(TASK_ID)) },
             { assertEquals(Instant.ofEpochSecond(87), reader.get(TASK_SUBMIT_TIME)) },
             { assertEquals(Duration.ofSeconds(11), reader.get(TASK_RUNTIME)) },
-            { assertEquals(setOf<String>("4", "5", "6"), reader.get(TASK_PARENTS)) },
+            { assertEquals(setOf("4", "5", "6"), reader.get(TASK_PARENTS)) },
         )
     }
 }