Cache data for post requests on server startup

Question

I have a large CSV file which needs to be parsed in order to make post requests to a REST API.The post request body is a json string. The first line in the file has keys and following lines are the values, e.g.

FirstName,LastName
John,Doe
Mark,Twain

So the post body will be something like {"FirstName":"John", "LastName":"Doe"}

This file will be used to create test data for the developers. I will provide a simple page where the developers can enter an account number and hit Submit. The goal is to parse this file and make POST requests to a REST API service.

I want to avoid reading the file each time a request comes in but rather cache these requests on startup to avoid the hassle of reading/parsing the file each time, so that each time a request comes in the request body simply needs to be retrieved from a cache . Is caching these POST request on startup the right way to go here ?

Also there might be a need to add more CSV files just to have variety of data. What would be a way to make this scalable ?

The format(key names) of the CSV file will be same so each file can be parsed in the same way.

score 0 · Answer 1 · answered Mar 04 '13 at 01:15

It can be implemented in N number of ways based on your requirement , here is a simple example. You can keep a class like

class Contact{
  private String firstName;
  private String lastName;
}

and in your other class which holds this value

class RestEnterpriseService{

  List<Contact> contacts;

  @PostConstruct
  init(){
    contacts = readFromJSON("JSON URL");
  }
}

score 0 · Answer 2 · edited Mar 04 '13 at 08:20

This can be done in several ways.

If you are using an Spring Framework or Java EE container, you can use the PostConstruct style solution as @AvinashSingh said above.

If you are in some Servlet container, you can do startup tasks using Servlet's Listener or other ways.

Also you can implement it your self, there are so many ways you can do that. Like using an guard variable to detect whether your contacts list is cached; or use skills which like Singleton Design Pattern.

Cache data for post requests on server startup

2 Answers2