Posted: 31/Jan/2024
The DynamoDB Go SDK expression package supports programmatic creation of Update expressions. Here is an example of how you can build an expression to include execute a SET operation of the UpdateItem API and combine it with a Condition expression (update criteria):
updateExpressionBuilder:=expression.Set(expression.Name("category"),expression.Value("standard"))conditionExpressionBuilder:=expression.AttributeNotExists(expression.Name("account_locked"))expr,_:=expression.NewBuilder().WithUpdate(updateExpressionBuilder).WithCondition(conditionExpressionBuilder).Build()resp,err:=client.UpdateItem(context.Background(),&dynamodb.UpdateItemInput{TableName:aws.String(tableName),Key:map[string]types.AttributeValue{"email":&types.AttributeValueMemberS{Value:"c1@foo.com"},},UpdateExpression:expr.Update(),ConditionExpression:expr.Condition(),ExpressionAttributeNames:expr.Names(),ExpressionAttributeValues:expr.Values(),ReturnValues:types.ReturnValueAllOld,})Recommended reading - WithUpdate method in the package API docs