I would like to get the relationships- authors-links-self, donno how to get it , Pls help me to get the self link

[jasminb]

I would like to get the relationships- authors-links-self, donno how to get it , Pls help me to get the self link

[jasminb]

Hello,

Can you please make sure that provided result is valid JSON.

[pradeepmallika]

@jasminb I have taken from http://jsonapi.org/examples/#error-objects-source-usage

and done small modification in relationship part.

[jasminb]

Hello @pradeepmallika,

Library does not allow direct access for relationship links in related objects, it allows for resolving relationships by implementing and registering relationship resolver.

This is the interface that needs to be implemented:

public interface RelationshipResolver {
    byte [] resolve(String relationshipURL);
}

Purpose of the resolver is to execute fetch using the relationship URL and than deserialise the response (it works transparently).

Now if you don't want this to happen automatically but still need to know the relationship URL, you can do the following:

public class MyCustomRelationshipResolver implements RelationshipResolver {
    private String relationshipURL;

    public  byte [] resolve(String relationshipURL) {
        this.relationshipURL = relationshipURL;
        return null;
    }

    public String getRelationshipURL() {
        return relationshipURL;
    }
}

Now, when you create your resource converter, do the following:

ResourceConverter converter = new ResourceConverter(...);

MyCustomRelationshipResolver customResolver = new MyCustomRelationshipResolver();
converter.setTypeResolver(customResolver, yourRelationshipTypeClass);

Now, after you execute a request, you will be able to get the relationship URL from the resolver by:

String url = customResolver.getRelationshipURL();

Please have in mind that this is a hack solution, proper solution would be to implement actual relationship resolver and use it to dereference linked relationships.

There is another more elaborate option that will be more clean but is more complicated:

Lets imagine you have following relationship type:

    @Type("relationship-type")
    public class RelationshipType {
        @Id
        private String id;

        @com.github.jasminb.jsonapi.annotations.Links
        private Links links;

        public String getId() {
            return id;
        }

        public void setId(String id) {
            this.id = id;
        }

        public Links getLinks() {
            return links;
        }

        public void setLinks(Links links) {
            this.links = links;
        }
    }

You could write following MyCustomRelationshipResolver:

public class MyCustomRelationshipResolver implements RelationshipResolver {
    private ResourceConverter converter;

    public MyCustomRelationshipResolver(ResourceConverter converter) {
        this.converter = converter;
    }

    public  byte [] resolve(String relationshipURL) {
        RelationshipType type = new RelationshipType();
        type.setId(UUID.randomUUID().toString());

        Link self = new Link(relationshipURL);
        Map<String, Link> linkMap = new HashMap<>();
        linkMap.put("self", self)
        type.setLinks(new Links(linkMap));

        try {
            return this.converter.writeDocument(new JSONAPIDocument<>(type));
        } catch (DocumentSerializationException e) {
            throw new RuntimeException(e);
        }
    }
}

If implemented like this, you will have your relationship object available with its Links attribute populated in the root object.

[pradeepmallika]

@jasminb Thanks for your detailed response ,I am using Retrofit , whether your solution can be used with Retrofit ?

[jasminb]

Sure it can, you need to create an instance of ResourceConverter to use it with retrofit, when you create it, you need to register type resolver with it.

[pradeepmallika]

@jasminb your email-id pls ?

[jasminb]

Hey @pradeepmallika, I would prefer to keep the discussion on this thread. If you need to share something you are not comfortable with sharing, you can change it in a way it does not expose any of your specifics and share it.

[pradeepmallika]

@jasminb We are using JSONAPIConverterFactory as a Library(I am not using source code,I am using only jar), in JSONAPIConverterFactory where i can create instance of ResourceConverter ? an working example will be help full.

[jasminb]

Hey @pradeepmallika, if you check https://github.com/jasminb/jsonapi-converter/blob/develop/src/main/java/com/github/jasminb/jsonapi/retrofit/JSONAPIConverterFactory.java, you can see that there are two different constructors that take ResourceConverter as arguments.

[pradeepmallika]

@jasminb I tired many ways , it is not working,an simple example with below given json will be useful , thanks in advance.

{
"data": {
"type": "articles",
"id": "1",
"attributes": {
"title": "JSON API paints my bikeshed!",
"body": "The shortest article. Ever.",
"created": "2015-05-22T14:56:29.000Z",
"updated": "2015-05-22T14:56:28.000Z"
},
"relationships": {
"author": {
"links": {
"self": "http://example.com/articles/1/relationships/author",
"related": "http://example.com/articles/1/author"
},
}
},
"included":
{
"type": "people",
"id": "42",
"attributes": {
"name": "John",
"age": 80,
"gender": "male"
}
}
}

[jasminb]

Hey @pradeepmallika, in this example the included section is not relevant since there is no type/id information in author relationship object. I can provide detailed example on how to get the relationship links if thats what you need.

[jasminb]

Hey @pradeepmallika, do you still need this?

[pradeepmallika]

@jasminb No ,thank you 👍