sinatra rest-client etag - sinatra

Question

My goal is to address "lost update problem" (see http://www.w3.org/1999/04/Editing/) in PUT operations.
I am using sinatra, and as a client I use rest_client. How I can check if it works? My client always return 200 code. Am I using arguments of calling it correctly? (PUT itself works)
sinatra code:
put '/players/:id' do |id|
etag 'something'
if Player[id].nil? then
halt 404
end
begin
data = JSON.parse(params[:data])
pl = Player[id]
pl.name = data['name']
pl.position = data['position']
if pl.save
"Resource modified."
else
status 412
redirect '/players'
end
rescue Sequel::DatabaseError
409 #Conflict - The request was unsuccessful due to a conflict in the state of the resource.
rescue Exception => e
400
puts e.message
end
end
client invocation:
player = {"name" => "John Smith", "position" => "def"}.to_json
RestClient.put('http://localhost:4567/players/1', {:data => player, :content_type => :json, :if_none_match => '"something"'}){ |response, request, result, &block|
p response.code.to_s + " " + response
}
I tried already to put :if_none_match => "something", I tried :if_match. Nothing changes.
How I can put headers into RestClient request?
How to obtain sth different than 200 status? (ie 304 not modified)?

Answer 1

Your payload and headers are in the same hash. You have to specify the headers for RestClient in second hash. Try:
player = {"name" => "John Smith", "position" => "def"}.to_json
headers = {:content_type => :json, :if_none_match => '"something"'}
RestClient.put('http://localhost:4567/players/1', {:data => player}, headers) do |response, request, result, &block|
p response.code.to_s + " " + response
end
I am not sure if RestClient translates the headers correctly. If the above doesn't work, try it with:
headers = {'Content-Type' => :json, 'If-None-Match' => '"something"'}