Sometimes you might need to receive a streaming response. You can do this with the on_data request option.

The on_data callback is a receives tuples of chunk Strings, and the total of received bytes so far.

This example implements such a callback:

# A buffer to store the streamed data
streamed = []

conn.get('/stream/10') do |req|
  # Set a callback which will receive tuples of chunk Strings
  # and the sum of characters received so far
  req.options.on_data = do |chunk, overall_received_bytes|
    puts "Received #{overall_received_bytes} characters"
    streamed << chunk

# Joins all response chunks together

The on_data streaming is currently only supported by some adapters. To see which ones, please refer to Awesome Faraday comparative table or check the adapter documentation.