Extract headers from a response — resp

resp_headers() retrieves a list of all headers.
resp_header() retrieves a single header.
resp_header_exists() checks if a header is present.

Usage

resp_headers(resp, filter = NULL)

resp_header(resp, header, default = NULL)

resp_header_exists(resp, header)

Arguments

resp: An HTTP response object, as created by req_perform().
filter: A regular expression used to filter the header names. NULL, the default, returns all headers.
header: Header name (case insensitive)
default: Default value to use if header doesn't exist.

Value

resp_headers() returns a list.
resp_header() returns a string if the header exists and NULL otherwise.
resp_header_exists() returns TRUE or FALSE.

Examples

resp <- request("https://httr2.r-lib.org") |> req_perform()
resp |> resp_headers()
#> <httr2_headers>
#> server: GitHub.com
#> content-type: text/html; charset=utf-8
#> last-modified: Tue, 16 Jul 2024 12:43:14 GMT
#> access-control-allow-origin: *
#> etag: W/"66966ae2-4724"
#> expires: Tue, 16 Jul 2024 13:21:16 GMT
#> cache-control: max-age=600
#> content-encoding: gzip
#> x-hosts-log-append: pages_hosts_ips:{ [1] = 10.0.3.157,[2] = 10.0.18.191,[3] = 10.0.34.194,}
#> x-proxy-cache: MISS
#> x-github-request-id: 896C:5EC2D:27D60AF:28F9AA0:66967173
#> accept-ranges: bytes
#> date: Tue, 16 Jul 2024 17:44:28 GMT
#> via: 1.1 varnish
#> age: 179
#> x-served-by: cache-pao-kpao1770028-PAO
#> x-cache: HIT
#> x-cache-hits: 4
#> x-timer: S1721151868.106914,VS0,VE0
#> vary: Accept-Encoding
#> x-fastly-request-id: 8a194f7475841776118f18d0638b95818efe83a2
#> content-length: 4555
resp |> resp_headers("x-")
#> <httr2_headers>
#> x-hosts-log-append: pages_hosts_ips:{ [1] = 10.0.3.157,[2] = 10.0.18.191,[3] = 10.0.34.194,}
#> x-proxy-cache: MISS
#> x-github-request-id: 896C:5EC2D:27D60AF:28F9AA0:66967173
#> x-served-by: cache-pao-kpao1770028-PAO
#> x-cache: HIT
#> x-cache-hits: 4
#> x-timer: S1721151868.106914,VS0,VE0
#> x-fastly-request-id: 8a194f7475841776118f18d0638b95818efe83a2

resp |> resp_header_exists("server")
#> [1] TRUE
resp |> resp_header("server")
#> [1] "GitHub.com"
# Headers are case insensitive
resp |> resp_header("SERVER")
#> [1] "GitHub.com"

# Returns NULL if header doesn't exist
resp |> resp_header("this-header-doesnt-exist")
#> NULL