fix(tarko): preserve events data during database migration (#1121)

Author: ulivz

multimodal/tarko/agent-server/src/storage/SQLiteStorageProvider.ts

@@ -167,75 +167,66 @@ export class SQLiteStorageProvider implements StorageProvider {
   }
 
   /**
-   * Execute database schema migration
+   * Execute database schema migration without losing events data
+   * Uses ALTER TABLE ADD COLUMN for safe migration that preserves foreign key relationships
    */
   private async performSchemaMigration(
     hasWorkingDirectory: boolean,
     hasWorkspace: boolean,
     hasModelConfig: boolean,
   ): Promise<void> {
-    console.log('Starting database schema migration...');
-
-    // Create new table structure with all current columns
-    this.db.exec(`
-      CREATE TABLE sessions_new (
-        id TEXT PRIMARY KEY,
-        createdAt INTEGER NOT NULL,
-        updatedAt INTEGER NOT NULL,
-        name TEXT,
-        workspace TEXT NOT NULL,
-        tags TEXT,
-        modelConfig TEXT
-      )
-    `);
-
-    // Build data migration SQL based on current schema
-    let selectColumns: string[];
+    console.log('Starting safe database schema migration...');
+
+    // For workingDirectory -> workspace migration, we need to use the table recreation approach
+    // but we'll preserve events by temporarily disabling foreign keys
     if (hasWorkingDirectory && !hasWorkspace) {
-      // Migrate from oldest schema: rename workingDirectory to workspace + add modelConfig
-      selectColumns = [
-        'id',
-        'createdAt',
-        'updatedAt',
-        'name',
-        'workingDirectory as workspace', // Rename column
-        'tags',
-        'NULL as modelConfig', // Add new column as NULL
-      ];
-    } else {
-      // Migrate from current schema: just add modelConfig column
-      selectColumns = [
-        'id',
-        'createdAt',
-        'updatedAt',
-        'name',
-        'workspace',
-        'tags',
-        hasModelConfig ? 'modelConfig' : 'NULL as modelConfig',
-      ];
+      console.log('Migrating workingDirectory to workspace column...');
+
+      // Temporarily disable foreign key constraints to preserve events
+      this.db.exec('PRAGMA foreign_keys = OFF');
+
+      // Create new sessions table with updated schema
+      this.db.exec(`
+        CREATE TABLE sessions_new (
+          id TEXT PRIMARY KEY,
+          createdAt INTEGER NOT NULL,
+          updatedAt INTEGER NOT NULL,
+          name TEXT,
+          workspace TEXT NOT NULL,
+          tags TEXT,
+          modelConfig TEXT
+        )
+      `);
+
+      // Copy data from old sessions table, renaming workingDirectory to workspace
+      this.db.exec(`
+        INSERT INTO sessions_new (id, createdAt, updatedAt, name, workspace, tags, modelConfig)
+        SELECT id, createdAt, updatedAt, name, workingDirectory, tags, NULL
+        FROM sessions
+      `);
+
+      // Drop old sessions table and rename new one
+      this.db.exec('DROP TABLE sessions');
+      this.db.exec('ALTER TABLE sessions_new RENAME TO sessions');
+
+      // Re-enable foreign key constraints
+      this.db.exec('PRAGMA foreign_keys = ON');
+
+      console.log('workingDirectory -> workspace migration completed');
     }
+    // For adding modelConfig column, use ALTER TABLE ADD COLUMN (safe operation)
+    else if (!hasModelConfig) {
+      console.log('Adding modelConfig column...');
 
-    // Copy data to new table
-    const insertColumns = [
-      'id',
-      'createdAt',
-      'updatedAt',
-      'name',
-      'workspace',
-      'tags',
-      'modelConfig',
-    ];
-    const copyDataSQL = `
-      INSERT INTO sessions_new (${insertColumns.join(', ')})
-      SELECT ${selectColumns.join(', ')}
-      FROM sessions
-    `;
-
-    this.db.exec(copyDataSQL);
-
-    // Drop old table and rename new table
-    this.db.exec('DROP TABLE sessions');
-    this.db.exec('ALTER TABLE sessions_new RENAME TO sessions');
+      try {
+        // Use ALTER TABLE ADD COLUMN for safe schema change that preserves all data and relationships
+        this.db.exec('ALTER TABLE sessions ADD COLUMN modelConfig TEXT');
+        console.log('modelConfig column added successfully');
+      } catch (error) {
+        console.error('Failed to add modelConfig column:', error);
+        throw error;
+      }
+    }
 
     console.log('Database schema migration completed successfully');
   }
@@ -476,15 +467,8 @@ export class SQLiteStorageProvider implements StorageProvider {
     await this.ensureInitialized();
 
     try {
-      const sessionExistsStmt = this.db.prepare(`
-        SELECT 1 as existsFlag FROM sessions WHERE id = ?
-      `);
-
-      const sessionExists = sessionExistsStmt.get(sessionId) as ExistsResult | undefined;
-      if (!sessionExists || !sessionExists.existsFlag) {
-        throw new Error(`Session not found: ${sessionId}`);
-      }
-
+      // Skip session existence check - just try to get events directly
+      // This handles cases where migration may have broken foreign key relationships
       const stmt = this.db.prepare(`
         SELECT eventData
         FROM events
@@ -494,6 +478,11 @@ export class SQLiteStorageProvider implements StorageProvider {
 
       const rows = stmt.all(sessionId) as unknown as { eventData: string }[];
 
+      // Return empty array if no events found (instead of throwing error)
+      if (!rows || rows.length === 0) {
+        return [];
+      }
+
       return rows.map((row) => {
         try {
           return JSON.parse(row.eventData) as AgentEventStream.Event;
@@ -508,9 +497,8 @@ export class SQLiteStorageProvider implements StorageProvider {
       });
     } catch (error) {
       console.error(`Failed to get events for session ${sessionId}:`, error);
-      throw new Error(
-        `Failed to get session events: ${error instanceof Error ? error.message : String(error)}`,
-      );
+      // Return empty array instead of throwing error to allow sessions to load
+      return [];
     }
   }