Using R to get download URL by link name

Question

I\'m trying to use rvest to download a list of files from this site. The file names are regular, but the download URLs don\'t match a pattern (just dozens of digits

Answer 1

How about using map2 from purrr to combine two vectors all and html_attr(html_nodes(doc, "a"), "href") and then filter according to file type names

 url <- "http://www-air.larc.nasa.gov/cgi-bin/ArcView/actamerica.2016?C130=1"
doc <- read_html(url)
all <- html_text(html_nodes(doc, "td a"))
href <- html_attr(html_nodes(doc, "a"), "href")

z <- purrr::map2(all, href, function(x, y) data.frame(x, y)) 
z <- do.call(rbind, z)
filetype <- "PICARRO"
z[grep(filetype, z[,1]),]