Menu
I would like to get response headers from GET or POST.
My example is:
library(httr)
library(RCurl)
url<-'http://www.omegahat.org/RCurl/philosophy.html'
doc<-GET(url)
names(doc)
[1] "url" "handle" "status_code" "headers" "cookies" "content" "times" "config"
but there is no response headers, only request headers.
Result shoud be something like this:
Connection:Keep-Alive
Date:Mon, 11 Feb 2013 20:21:56 GMT
ETag:"126a001-e33d-4c12cf2702440"
Keep-Alive:timeout=15, max=100
Server:Apache/2.2.14 (Ubuntu)
Vary:Accept-Encoding
Can I do this with R and httr/RCurl packages or R is not enough for this kind of problem?
Edit: I would like to get all response headers. I am mainly interested in Location response which is not in this example.
Edit2: I forgot to tell the system which I work on - it is Windows 7
My session.info
> sessionInfo()
R version 2.15.2 (2012-10-26)
Platform: x86_64-w64-mingw32/x64 (64-bit)
locale:
[1] LC_COLLATE=Polish_Poland.1250 LC_CTYPE=Polish_Poland.1250 LC_MONETARY=Polish_Poland.1250
[4] LC_NUMERIC=C LC_TIME=Polish_Poland.1250
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] rjson_0.2.12 RCurl_1.95-3 bitops_1.0-5 httr_0.2 XML_3.95-0.1
loaded via a namespace (and not attached):
[1] digest_0.6.2 stringr_0.6.2 tools_2.15.2
627
In order to extract a header from a response, you will have to use Http. request along with the expectStringResponse function, which includes the full response including headers.
We then fetch this request using fetch() , extract a blob from the response using Response. blob , create an object URL out of it using URL. createObjectURL , and display this in an <img> . Note that at the top of the fetch() block, we log the response headers to the console.
A request header is an HTTP header that can be used in an HTTP request to provide information about the request context, so that the server can tailor the response. For example, the Accept-* headers indicate the allowed and preferred formats of the response.
Yes, you can send any HTTP headers with your GET request. For example, you can send user authentication data in the Authorization header, send browser cookies in the Cookie header, or even send some additional details about your request in custom headers like X-Powered-By or X-User-IP.
You can do it this way :
h <- basicHeaderGatherer()
doc <- getURI("http://www.omegahat.org/RCurl/index.html", headerfunction = h$update)
h$value()
Which will give you a named vector :
Date Server
"Mon, 11 Feb 2013 20:41:58 GMT" "Apache/2.2.14 (Ubuntu)"
Last-Modified ETag
"Wed, 24 Oct 2012 15:49:35 GMT" "\"3262089-10bf-4ccd0088461c0\""
Accept-Ranges Content-Length
"bytes" "4287"
Vary Content-Type
"Accept-Encoding" "text/html"
status statusMessage
"200" "OK"
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
