Array of hashes param not being parsed correctly in a spec

[elado]

It might be a Rack issue, but:

before do
  subject.params do
    requires :contacts, type: Array do
      optional :name
      optional :phone
      optional :email
    end
  end

  subject.before_validation do
    pp form_vars: env['rack.request.form_vars'], form_hash: env['rack.request.form_hash']
    pp before: params.to_h
  end

  subject.post '/post' do
  end
end

it 'posts an array of hashes' do
  post '/post', contacts: [
    { name: 'John', phone: '123' },
    { email: 'a@mail.com' },
    { name: 'Doe', email: 'b@mail.com' },
  ]
end

Output is:

{:form_vars=>
  "contacts[][name]=John&contacts[][phone]=123&contacts[][email]=a%40mail.com&contacts[][name]=Doe&contacts[][email]=b%40mail.com",
 :form_hash=>
  {"contacts"=>
    [{"name"=>"John", "phone"=>"123", "email"=>"a@mail.com"},
     {"name"=>"Doe", "email"=>"b@mail.com"}]}}
{:before=>
  {"contacts"=>
    [{"name"=>"John", "phone"=>"123", "email"=>"a@mail.com"},
     {"name"=>"Doe", "email"=>"b@mail.com"}]}}

Rack(?) couldn't infer where each element starts so it combined both first items.

For a workaround I can send a Hash {0=>{name: ..., email:}, 1=>{email: ...}} and before validation do:

params[:contacts] = params[:contacts].values if params[:contacts].is_a?(Hash)

Any other suggestions?

[dblock]

This looks legit, but I am not sure how to fix it. Arrays of hashes is not exactly something you can express in a query string.

For something like this I would POST JSON.

[elado]

The client sends JSON body so I'm covered there.

Maybe, if a param is defined as a type: Array and it looks like a hash with numeric keys it should convert automatically to an array of the values?
I understand why Rack does what it does, the only solution I see is not using key-less params (as in contacts[] but contacts[0]).

[dblock]

I would just let this go, but it's me :)

[dm1try]

@elado I would use a midlleware to convert hashes with numeric keys to array.
For example the similar is already implemented here (spec)

[elado]

@dm1try thanks!

[martinverdejo]

Having the same problem now..

My HTTP post request has to pass in form data that looks like this:

listings_attributes[0][count] = 1
listings_attributes[1][name] = "Ipsum"
listings_attributes[1][count] = 2
listings_attributes[2][name] = "Dolor"
listings_attributes[2][count] = 3

This is represented as a ruby hash with numeric keys. Is there a way to declare the params so that the presence and type validations apply in my endpoint?

Tried the following param declaration

requires :listings_attributes, type: Array do
  optional :name, type: String
  optional :count, type: Integer
end

but this results in

(Grape::Exceptions::ValidationErrors) - listings_attributes is invalid

[dblock]

@martinverdejo post a repro, and see my comment