Fix for https://github.com/crystal-community/cossack/issues/16

src/cossack/connection/http_connection.cr

@@ -2,11 +2,22 @@ module Cossack
   # A connection to perform a real HTTP request using the standard library.
   class HTTPConnection < Connection
     def call(request : Request) : Response
-      client = HTTP::Client.new(request.uri)
+      uri = request.uri
+      scheme = uri.scheme
+      uri_host = uri.host
+      client = if uri_host.nil?
+        HTTP::Client.new(uri)
+      else
+        HTTP::Client.new(uri_host, uri.port, scheme == "https")
+      end
+
       client.connect_timeout = request.options.connect_timeout
       client.read_timeout = request.options.read_timeout
 
-      http_response = client.exec(request.method, request.uri.path, request.headers, request.body)
+      uri_string = uri.to_s
+      base_url = uri.port.nil? ? "#{scheme}://#{uri_host}" : "#{scheme}://#{uri_host}:#{uri.port}"
+      path = uri_string.starts_with?(base_url) ? uri_string[base_url.size, uri_string.size - base_url.size] : uri_string
+      http_response = client.exec(request.method, path, request.headers, request.body)
       Response.new(http_response.status_code, http_response.headers, http_response.body)
     rescue err : IO::TimeoutError
       raise TimeoutError.new(err.message, cause: err)