decode tinyurl in R to get full url path? decode tinyurl in R to get full url path? r r

decode tinyurl in R to get full url path?


Below is a quick and dirty solution, but should get the job done:

library(RCurl)decode.short.url <- function(u) {  x <- try( getURL(u, header = TRUE, nobody = TRUE, followlocation = FALSE) )  if(class(x) == 'try-error') {    return(u)  } else {    x <- strsplit(x, "Location: ")[[1]][2]    return(strsplit(x, "\r")[[1]][1])  }}

The variable 'u' below contains one shortend url, and one regular url.

u <- c("http://tinyurl.com/adcd", "http://www.google.com") 

You can then get the expanded results by doing the following.

 sapply(u, decode.short.url) 

The above should work for most services which shorten the URL, not just tinyURL. I think.

HTH

Tony Breyal


I don't know R but in general you need to make a http request to the tinyurl-url. You should get back a 301 response with the actual url.


I used Tony Breyal's code, but the function returned NA values for those URLs where there was no URL redirection. Even though Tony listed "google.com" in his example, I think Google redirects you in any case to some sort of localized version of google.com.

Here is how I modified Tony's code to deal with that:

decode.short.url <- function(u) {  x <- try( getURL(u, header = TRUE, nobody = TRUE, followlocation = FALSE) )  if(class(x) == 'try-error') {    print(paste("***", u, "--> ERORR!!!!"))        return(u)  } else {    x <- strsplit(x, "Location: ")[[1]][2]    x.2  <- strsplit(x, "\r")[[1]][1]    if (is.na(x.2)){      print(paste("***", u, "--> No change."))      return(u)    }else{      print(paste("***", x.2, "--> resolved in -->", x.2))        return(x.2)    }  }}u <- list("http://www.amazon.com", "http://tinyurl.com/adcd") urls <- sapply(u, decode.short.url)