Trying to parse request body in Grape API - rack

Question

So I have an API where one of the entry points looks something like:
module SomeModule
module SomeOtherModule
class Users < SomeModule::SomeOtherModule::Base
helpers do
params :user do
requires :user, type: Hash do
requires :device_id, type: String, desc: "Device ID"
end
end
end
desc "Some description"
params do
use :user
end
put "/", route_name: :v1_put_user_path do
...
end
end
end
end
SomeModule::SomeOtherModule::Base inherits from Grape::API
My client is sending the params in the body - which look like:
{"user[device_id]":"xyz"}
Since this come like a string the I fail to recognise them.Therefore return:
{"error":"user is missing"}
This means that on my server I'm getting:
{"user[device_id]"=>"00999877",
"route_info"=>
...
When I'm expecting to see:
{"user"=>{"device_id"=>"00999877"},
"route_info"=>
...
Any ideas on how should I define my params?...or maybe someone has stumble upon this issue and can provide some solution

Answer 1

You have to define your params block like this:
module SomeModule
module SomeOtherModule
class Users < SomeModule::SomeOtherModule::Base
params do
group :user, type: Hash do
requires :device_id, type: String, desc: "Device ID"
end
end
put "/", route_name: :v1_put_user_path do
...
end
end
end
end
UPDATE
Explaining the solution...
If your client is sending a JSON like the code below, then you have to define a group block and define the type parameter as Hash. The same rule applies when your client sends a "form-field" like user[device_id].
{ user: { device_id: 1 } }
UPDATE 2
I've just noticed that your client is sending an incorrect JSON to your service. This JSON shouldn't be...
{"user[device_id]":"xyz"}
...because it's not what your API is expecting. Instead, it should send
{ user: { device_id: "xyz" } }.