CODEWITHSUNDEEP
javaspringrestjacksonexport-to-csv
ST-DDT
ST-DDT

Reputation: 2707

Ignore different fields in CSV and JSON

I have s Spring REST API that usually just outputs JSON.

Now I want to also export CSVs for some endpoints.

Jackson has a library for that 

<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-csv</artifactId>
    <version>2.8.5</version>
</dependency>

Which I can utilize using Spring's HttpMessageConverter.

However I need to exclude some fields in the CSV that are present in the JSON thus I cannot use @JsonIgnore annotation. Is there a way to use a different ignore property/annotation for CSV?

As an alternative i considered using a custom interface to extract the values to serialize the values before hand. List<CSVableDTO> -> List<Map<String,?>> -> CSV. But I would like to avoid that because it involves extra instance creation and extra coding vs just using a new annotation.

Java-Class-Example:

public class MyDTO {

    @CSVIgnore
    public int id;
    public String name;
    public String property;
    @CSVIgnore
    public String ref;

}

JSON-Example:

[
    {
        "id": 42,
        "name": "Example",
        "property": "FooBar",
        "ref": "42:Not:FooBar:1337"
    }
]

Expected-CSV-Result:

"name";"property"
"Example";"FooBar"

Upvotes: 2

Views: 1684

Answers (1)

Andremoniy
Andremoniy

Reputation: 34900

Please, consider usage of JsonView mechanism. You will have something like that:

public class Foo {

     public interface JsonOnly{}
     public interface CsvView{}

     @JsonView(JsonOnly.class) 
     private Integer secretNotForCsv;

     // ...

}

@RestController
public class FooController {

       @RequestMapping(...)
       @JsonView(Foo.JsonOnly.class)
       public Foo getJson() {
           // ...
       }

       @RequestMapping(...)
       @JsonView(Foo.CsvView.class)
       public Foo getCsv() {
           // ...
       }
}

This is only a very rough sketch, but it should give you an idea.

Upvotes: 1

Related Questions