How do I map the JSON body of a GET request to a parameter?

Question

I have the following definition in my endpoint:

params do
    requires :entities do
      requires :id, type: String
      optional :email, type: String
      optional :phone, type: String
    end
  end
  post "test" do

  end

Note this only works as a POST request and the following CURL will work:

curl -XPOST localhost/test 
     -H 'Content-Type: application/json' 
     -H 'Accept: application/json' 
     -d '{ "entities": [{ "id": 3, "email": "test@abc.com" }] }'

However, the moment I change the declaration to get "test" instead of post, the corresponding curl request with -XGET no longer works due to the following validation error:

{"error":"entities is missing"}

If I remove the params requirements I can manually inspect the params hash at runtime and see that it only has a single key "route_info"

I'm currently using Grape 0.7.0

score 1 · Accepted Answer · edited May 23 '17 at 12:15

It happens because by specifying -d option you pass parameters in the body of the request while your endpoint is expecting them in the path as part of the url. Check here why it's a bad idea to pass body parameters in a GET request.

However, can use that option but if combination with -G.

-G, --get

When used, this option will make all data specified with -d, --data, --data-binary or --data-urlencode to be used in an HTTP GET request instead of the POST request that otherwise would be used. The data will be appended to the URL with a '?' separator.

So that your get request by using -d would look like:

curl -XGET -G localhost/test 
     -H 'Content-Type: application/json' 
     -H 'Accept: application/json' 
     -d '{ "entities": [{ "id": 3, "email": "test@abc.com" }] }'

Thanks for the link - makes sense. Incidentally, turns out that jQuery converts XHR get requests into query-string encoded variables too. I'll just use POST - I thought GET made sense semantically since it didn't change the state of the domain model and I don't want to be limited by URL-length issues, but alas — blue18hutthutt, Nov 16 '15 at 19:35

How do I map the JSON body of a GET request to a parameter?

1 Answers1