Rails send four backslashes using Net::HTTP - php

Question

My rails application need to send some data to a php application, which expects a POST call.
I use the folowing code:
uri = URI.parse(apiUrl)
req = Net::HTTP::Post.new(uri.to_s, initheader = {'Content-Type' =>'application/json'})
req.basic_auth(api_key, token)
req.set_form_data({"action" => action, "data" => data})
http = Net::HTTP.new(uri.host, uri.port)
response = http.request(req)
Where data is a hash converted to json:
data = {
:key1 => val1,
:key2 => val2
}.to_json
(it is a nested hash, i.e. some values are hash as well)
My problem is that the php application receives 4 backslashes before each quotation mark:
$data_json = $_POST['data'];
error_log($data_json);
and in error log I see:
'{\\\\"key1\\\\":val1,\\\\"key2\\\\":\\\\"val2\\\\"}'
Looks like rails add one of them, but even if I remove it and replace it with the following code:
a.gsub!(/\"/, '\'')
I still get many backslashes inside the php application, hence cannot convert the string to array.
Any idea??

Answer 1

By using set_form_data net/http is POSTing the form as urlencoded. Its NOT posting your request body as pure JSON.
If you want to POST raw JSON you will need to follow a pattern like:
uri = URI('https://myapp.com/api/v1/resource')
req = Net::HTTP::Post.new(uri, initheader = {'Content-Type' =>'application/json'})
req.body = {param1: 'some value', param2: 'some other value'}.to_json
res = Net::HTTP.start(uri.hostname, uri.port) do |http|
http.request(req)
end