Android Retrofit return status 500 internal server

问题:

I am using Retrofit like this to get all the books and delete all the books.

 @GET("/books")
    BookListResponse getAllBooks();
    @DELETE("/clean")
    Response deleteAllBooks();

But an error status 500 (internal server error) was returned. I tested these two restful calls using Chrome restful client app and they work properly.

However, if I just want to get one book or delete one book like this

 @GET("books/1")
    BookResponse getOneBook();
    @DELETE("books/1")
    Response deleteOneBook();

They can work properly.

So I am not sure if that's the server issue or I have missed something?

回答1:

This is just a matter of semantics: when you say to your server "Please delete book", but you don't say which book you want to delete, the server don't know what to do (this happens when you send a DELETE to /books). Hence the error 500. But when you say "Please delete book with id 1", now the server knows what to do (this happens when you send a DELETE to /books/1).

It is ok to work that way if you setup your server like this, but I've never seen any REST service to delete ALL records of a particular model. Again, if you coded your server this way it is ok, just make sure the request is reaching the server the way you want.

After all, if you got a error 500, check your server. The problem isn't in the Android side, definitely.

回答2:

Just add the header accept in the request as follow:

Request request = new Request.Builder()
                .url(urlString)
                .header("accept", "application/json")
                .build();

回答3:

Update
In Retrofit 2.1 the request builder has changed so you have to specify header in the retrofit interface methods

@Headers("Accept: application/json") @GET("products") Call<Products> getAllProducts();