req_perform_connection: Perform a request and return a streaming connection

In r-lib/httr2: Perform HTTP Requests and Process the Responses

Perform a request and return a streaming connection

Description

Use req_perform_connection() to perform a request if you want to stream the response body. A response returned by req_perform_connection() includes a connection as the body. You can then use resp_stream_raw(), resp_stream_lines(), or resp_stream_sse() to retrieve data a chunk at a time. Always finish up by closing the connection by calling close(response).

This is an alternative interface to req_perform_stream() that returns a connection that you can use to pull the data, rather than providing callbacks that the data is pushed to. This is useful if you want to do other work in between handling inputs from the stream.

Usage

req_perform_connection(req, blocking = TRUE, verbosity = NULL)

Arguments

req	A httr2 request object.
blocking	When retrieving data, should the connection block and wait for the desired information or immediately return what it has (possibly nothing)?
verbosity	How much information to print? This is a wrapper around req_verbose() that uses an integer to control verbosity: 0: no output 1: show headers 2: show headers and bodies 3: show headers, bodies, and curl status messages. Use with_verbosity() to control the verbosity of requests that you can't affect directly.

Examples

req <- request(example_url()) |>
  req_url_path("/stream-bytes/32768")
resp <- req_perform_connection(req)

length(resp_stream_raw(resp, kb = 16))
length(resp_stream_raw(resp, kb = 16))
# When the stream has no more data, you'll get an empty result:
length(resp_stream_raw(resp, kb = 16))

# Always close the response when you're done
close(resp)

r-lib/httr2 documentation built on Jan. 11, 2025, 10:21 a.m.