在erlang视图中发出嵌套哈希值

Question

i try to emit the postal_country in my view and i have no idea how this would be done in erlang.

this is the structure of my document:

{
   ...
   "postal_address": {
       "postal_country": "BE"
       ...
   }
}

this is the js i want to translate:

function(doc) {
  if (doc['ruby_class'] == 'Company' && doc['postal_address']['postal_country']) {
    emit(doc['postal_address']['postal_country'], 1)
  }
}

this is what i tried in erlang:

fun({Doc}) ->
  case proplists:get_value(<<"ruby_class">>, Doc) of
    <<"Company">> ->
      Addr = proplists:get_value(<<"postal_address">>, Doc, null), 
      Key = proplists:get_value(<<"postal_country">>, Addr, null),
      Emit(Key, 1);
    _ ->
    ok
  end
end.

Answer 1

You need to unwrap Address as suggested at https://stackoverflow.com/a/2422631/453605 :

fun({Doc}) ->
  case proplists:get_value(<<"ruby_class">>, Doc) of
    <<"Company">> ->
      case proplists:get_value(<<"postal_address">>, Doc) of
        {Address} ->
          Country = proplists:get_value(<<"postal_country">>, Address),
          Emit(Country, 1);
        _ ->
          ok
      end;
    _ ->
      ok
  end
end.