How to query upon the given parameters in Mongo repository - spring-boot

Question

I have a mongo repostiory query as below, If we provide both name and price it gives the response. I want to get response if we only give name or price or both. how to make those parameters optional. if we provide both name and price i want to retrieve aggregated result unless i want to search just from the given field. Much appreciate you help.
List<Response> findByNameAndPrice(String name, int price)

Answer 1

Either you may need to implement custom JPA query or need to use QueryDSL in such scenarios.
1) Custom JPA Query like, you may need to change the query if you want to ad new optional parameters.
#Query(value = "{$or:[{name: ?0}, {?0: null}], $or:[{price: ?1}, {?1: null}]}")
List<Response> findByNameAndPrice(String name, Integer price)
2) QueryDSL Approach where you can add as many optional parameters, no need to modify your code. It will generate query automatically.
Refer this link for more : Spring Data MongoDB Repository - JPA Specifications like

Answer 2

I don't believe you'll be able to do that with the method name approach to query definition. From the documentation (reference):
There is a JIRA ticket regarding this which is still under investigation by the Spring team.
You can try this way
In repository
List<Response> findByName(String name)
List<Response> findByPrice(int price)
List<Response> findByNameAndPrice(String name, int price)
In your service file
public List<Response> findByNameAndPrice(String name, int price){
if(name == null ){
return repository.findByName(name);
}
if( price == 0){
return repository.findByPrice(price);
}
return repository.findByNameAndPrice(name, price);
}

Answer 3

Here I found a simple solution using mongodb regex,we can write a query like this,
#Query("{name : {$regex : ?0}, type : {$regex : ?1})List<String> findbyNameAndType(String name, String type)
The trick is if we want to query upon the given parameter, we should set other parameters some default values. As an example here thinks we only provide name. Then we set the type to select its all possible matches by setting its default param as ".*".
This regex pattern gives any string match.