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.

4 files changed, 5 insertions, 5 deletions

diff --git a/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormat.kt b/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormat.kt
index 11d21a04..82e454ad 100644
--- a/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormat.kt
+++ b/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormat.kt
@@ -72,7 +72,7 @@ public class BitbrainsExTraceFormat : TraceFormat {
         }
     }
 
-    override fun newReader(path: Path, table: String): TableReader {
+    override fun newReader(path: Path, table: String, projection: List<TableColumn<*>>?): TableReader {
         return when (table) {
             TABLE_RESOURCE_STATES -> newResourceStateReader(path)
             else -> throw IllegalArgumentException("Table $table not supported")
diff --git a/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormat.kt b/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormat.kt
index e1e7604a..a374e951 100644
--- a/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormat.kt
+++ b/opendc-trace/opendc-trace-bitbrains/src/main/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormat.kt
@@ -81,7 +81,7 @@ public class BitbrainsTraceFormat : TraceFormat {
         }
     }
 
-    override fun newReader(path: Path, table: String): TableReader {
+    override fun newReader(path: Path, table: String, projection: List<TableColumn<*>>?): TableReader {
         return when (table) {
             TABLE_RESOURCES -> {
                 val vms = Files.walk(path, 1)
diff --git a/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormatTest.kt b/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormatTest.kt
index 77429e3e..c944cb98 100644
--- a/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormatTest.kt
+++ b/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsExTraceFormatTest.kt
@@ -59,7 +59,7 @@ internal class BitbrainsExTraceFormatTest {
     @Test
     fun testSmoke() {
         val path = Paths.get("src/test/resources/vm.txt")
-        val reader = format.newReader(path, TABLE_RESOURCE_STATES)
+        val reader = format.newReader(path, TABLE_RESOURCE_STATES, null)
 
         assertAll(
             { assertTrue(reader.nextRow()) },
diff --git a/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormatTest.kt b/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormatTest.kt
index 9309beb1..841801e6 100644
--- a/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormatTest.kt
+++ b/opendc-trace/opendc-trace-bitbrains/src/test/kotlin/org/opendc/trace/bitbrains/BitbrainsTraceFormatTest.kt
@@ -57,7 +57,7 @@ class BitbrainsTraceFormatTest {
     @Test
     fun testResources() {
         val path = Paths.get("src/test/resources/bitbrains.csv")
-        val reader = format.newReader(path, TABLE_RESOURCES)
+        val reader = format.newReader(path, TABLE_RESOURCES, null)
 
         assertAll(
             { assertTrue(reader.nextRow()) },
@@ -71,7 +71,7 @@ class BitbrainsTraceFormatTest {
     @Test
     fun testSmoke() {
         val path = Paths.get("src/test/resources/bitbrains.csv")
-        val reader = format.newReader(path, TABLE_RESOURCE_STATES)
+        val reader = format.newReader(path, TABLE_RESOURCE_STATES, null)
 
         assertAll(
             { assertTrue(reader.nextRow()) },