Make Snowflake QUERY_ACCELERATION_HISTORY optional (#353)

The extraction of Snowflake `QUERY_ACCELERATION_HISTORY` table is sometimes not
possible, therefore I'm changing the TaskCategory from `REQUIRED` to
`OPTIONAL`, so that the extraction doesn't fail in case this table is
not available.

Additionally, cleanup the `TeradataJdbcSelectTask` class, because
otherwise the `TeradataJdbcSelectTask` class would contain a duplicated
code between it and the `JdbcSelectTask` class.

dumper/app/src/main/java/com/google/edwmigration/dumper/application/dumper/connector/snowflake/SnowflakeLogsConnector.java

@@ -34,6 +34,7 @@
 import com.google.edwmigration.dumper.application.dumper.task.FormatTask;
 import com.google.edwmigration.dumper.application.dumper.task.JdbcSelectTask;
 import com.google.edwmigration.dumper.application.dumper.task.Task;
+import com.google.edwmigration.dumper.application.dumper.task.TaskCategory;
 import com.google.edwmigration.dumper.plugin.ext.jdk.annotation.Description;
 import com.google.edwmigration.dumper.plugin.lib.dumper.spi.SnowflakeLogsDumpFormat;
 import com.google.errorprone.annotations.ForOverride;
@@ -135,11 +136,22 @@ private static class TaskDescription {
     private final String unformattedQuery;
     private final Class<? extends Enum<?>> headerClass;
 
+    private final TaskCategory taskCategory;
+
     private TaskDescription(
         String zipPrefix, String unformattedQuery, Class<? extends Enum<?>> headerClass) {
-      this.unformattedQuery = unformattedQuery;
+      this(zipPrefix, unformattedQuery, headerClass, TaskCategory.REQUIRED);
+    }
+
+    private TaskDescription(
+        String zipPrefix,
+        String unformattedQuery,
+        Class<? extends Enum<?>> headerClass,
+        TaskCategory taskCategory) {
       this.zipPrefix = zipPrefix;
+      this.unformattedQuery = unformattedQuery;
       this.headerClass = headerClass;
+      this.taskCategory = taskCategory;
     }
   }
 
@@ -381,7 +393,7 @@ private static void addJdbcTask(
         task.zipPrefix
             + DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(interval.getStartUTC())
             + ".csv";
-    out.add(new JdbcSelectTask(file, query).withHeaderClass(task.headerClass));
+    out.add(new JdbcSelectTask(file, query, task.taskCategory).withHeaderClass(task.headerClass));
   }
 
   private String getOverrideableQuery(
@@ -495,7 +507,8 @@ private List<TaskDescription> createTimeSeriesTasks(ConnectorArguments arguments
                     parseColumnsFromHeader(QueryAccelerationHistoryFormat.Header.class),
                     "QUERY_ACCELERATION_HISTORY"),
                 "END_TIME"),
-            QueryAccelerationHistoryFormat.Header.class),
+            QueryAccelerationHistoryFormat.Header.class,
+            TaskCategory.OPTIONAL),
         new TaskDescription(
             ReplicationGroupUsageHistoryFormat.ZIP_ENTRY_PREFIX,
             getOverrideableQuery(

dumper/app/src/main/java/com/google/edwmigration/dumper/application/dumper/connector/teradata/AbstractTeradataConnector.java

@@ -121,17 +121,10 @@ public String getDescription() {
   protected static class TeradataJdbcSelectTask extends JdbcSelectTask {
 
     private final String sqlCount;
-    private final TaskCategory category;
 
     public TeradataJdbcSelectTask(String targetPath, TaskCategory category, String sqlTemplate) {
-      super(targetPath, String.format(sqlTemplate, "*"));
+      super(targetPath, String.format(sqlTemplate, "*"), Preconditions.checkNotNull(category));
       this.sqlCount = sqlTemplate.contains("%s") ? String.format(sqlTemplate, "count(*)") : null;
-      this.category = Preconditions.checkNotNull(category);
-    }
-
-    @Override
-    public TaskCategory getCategory() {
-      return category;
     }
 
     // This works to execute the count SQL on the same connection as the data SQL,

dumper/app/src/main/java/com/google/edwmigration/dumper/application/dumper/task/JdbcSelectTask.java

@@ -33,9 +33,23 @@ public class JdbcSelectTask extends AbstractJdbcTask<Summary> {
 
   @Nonnull private final String sql;
 
+  @Nonnull private final TaskCategory taskCategory;
+
   public JdbcSelectTask(@Nonnull String targetPath, @Nonnull String sql) {
+    this(targetPath, sql, TaskCategory.REQUIRED);
+  }
+
+  public JdbcSelectTask(
+      @Nonnull String targetPath, @Nonnull String sql, TaskCategory taskCategory) {
     super(targetPath);
     this.sql = sql;
+    this.taskCategory = taskCategory;
+  }
+
+  @Override
+  @Nonnull
+  public TaskCategory getCategory() {
+    return taskCategory;
   }
 
   @Nonnull