Improve DatabaseSchemaCreator

Create locks and refs tables in one array of statements instead of
issuing two separate updates.

Change-Id: Ida11c6da8df15ef1f05a3b04470cac5b8be74851

src/main/java/com/googlesource/gerrit/plugins/spannerrefdb/DatabaseSchemaCreator.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/spannerrefdb/DatabaseSchemaCreator.java b/src/main/java/com/googlesource/gerrit/plugins/spannerrefdb/DatabaseSchemaCreator.java
index 7bed262..2990a1b 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/spannerrefdb/DatabaseSchemaCreator.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/spannerrefdb/DatabaseSchemaCreator.java
@@ -15,17 +15,13 @@
 package com.googlesource.gerrit.plugins.spannerrefdb;
 
 import com.gerritforge.gerrit.globalrefdb.GlobalRefDbSystemError;
-import com.google.api.gax.longrunning.OperationFuture;
 import com.google.cloud.spanner.DatabaseAdminClient;
 import com.google.cloud.spanner.DatabaseId;
-import com.google.cloud.spanner.ErrorCode;
-import com.google.cloud.spanner.SpannerException;
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.extensions.events.LifecycleListener;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
-import com.google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata;
-import java.util.Arrays;
+import java.util.List;
 
 @Singleton
 class DatabaseSchemaCreator implements LifecycleListener {
@@ -42,47 +38,38 @@
 
   @Override
   public void start() {
-    createTable(
-        "CREATE TABLE refs ("
-            + "project  STRING(MAX) NOT NULL,"
-            + "ref  STRING(MAX) NOT NULL,"
-            + "value  STRING(MAX) NOT NULL"
-            + ") PRIMARY KEY (project, ref)");
-    createTable(
-        "CREATE TABLE locks ("
-            + "project  STRING(MAX) NOT NULL,"
-            + "ref  STRING(MAX) NOT NULL,"
-            + "heartbeat TIMESTAMP OPTIONS ("
-            + "    allow_commit_timestamp = true"
-            + "),"
-            + "token TIMESTAMP OPTIONS ("
-            + "    allow_commit_timestamp = true"
-            + "),"
-            + "owner STRING(MAX) NOT NULL"
-            + ") PRIMARY KEY (project, ref)");
+
+    try {
+      dbAdminClient
+          .updateDatabaseDdl(
+              dbId.getInstanceId().getInstance(),
+              dbId.getDatabase(),
+              List.of(
+                  "CREATE TABLE IF NOT EXISTS refs"
+                      + "("
+                      + "project STRING(MAX) NOT NULL,"
+                      + "ref STRING(MAX) NOT NULL,"
+                      + "value STRING(MAX) NOT NULL"
+                      + ")"
+                      + "PRIMARY KEY (project, ref)",
+                  "CREATE TABLE IF NOT EXISTS locks"
+                      + "("
+                      + "project STRING(MAX) NOT NULL,"
+                      + "ref STRING(MAX) NOT NULL,"
+                      + "heartbeat TIMESTAMP OPTIONS (allow_commit_timestamp = true),"
+                      + "token TIMESTAMP OPTIONS (allow_commit_timestamp = true),"
+                      + "owner STRING(MAX) NOT NULL"
+                      + ")"
+                      + "PRIMARY KEY (project, ref)"),
+              null)
+          .get();
+    } catch (Exception e) {
+      throw new GlobalRefDbSystemError(
+          String.format("Failed to create schema in database [%s]", dbId), e);
+    }
+    logger.atInfo().log("Created schema in database [%s]", dbId);
   }
 
   @Override
   public void stop() {}
-
-  private void createTable(String statement) {
-    try {
-      OperationFuture<Void, UpdateDatabaseDdlMetadata> op =
-          dbAdminClient.updateDatabaseDdl(
-              dbId.getInstanceId().getInstance(),
-              dbId.getDatabase(),
-              Arrays.asList(statement),
-              null);
-      op.get();
-      logger.atInfo().log("Created table in database [%s] with statement %s", dbId, statement);
-    } catch (Exception e) {
-      Throwable cause = e.getCause();
-      if (cause instanceof SpannerException) {
-        ErrorCode code = ((SpannerException) cause).getErrorCode();
-        if (code != ErrorCode.FAILED_PRECONDITION) {
-          throw new GlobalRefDbSystemError("Failed to create table", e);
-        }
-      }
-    }
-  }
 }