Proper DB migration

migration/users.1.cr

@@ -0,0 +1,20 @@
+class CreateUsers < MG::Base
+  def up : String
+    <<-SQL
+    CREATE TABLE IF NOT EXISTS users (
+      username TEXT NOT NULL,
+      password TEXT NOT NULL,
+      token TEXT,
+      admin INTEGER NOT NULL
+    );
+    CREATE UNIQUE INDEX IF NOT EXISTS username_idx ON users (username);
+    CREATE UNIQUE INDEX IF NOT EXISTS token_idx ON users (token);
+    SQL
+  end
+
+  def down : String
+    <<-SQL
+    DROP TABLE users;
+    SQL
+  end
+end