Reputation: 601
I would like to download HTML webpages from www.geocaching.com in order to scrape some information. However the webpages I want to download have two ways of being displayed depending on whether the user is logged in. The information I want to scrape is only found when the user is logged in.
In the past I have used download.file()
and mapply()
to download HTML files from a list of URLs (geocache_link_list
) and name them using another list (geocache_name_list
) like this:
mapply(function(x,y) download.file(x,y), geocache_link_list, geocache_name_list)
but this downloads the non-logged in page.
I tried to use RCurl
also, but this also downloaded the non-logged in page and so I never attempted to incorporate it into a mapply function:
library(RCurl)
baseurl <- geocache_link_list[1]
un <- readline("Type the username:")
pw <- readline("Type the password:")
upw <- paste(un, pw, sep = ":")
Is there a way to run a browser from within R using something like RSelenium
or RCurl
in order to enter login details then redirect to the desired pages and download them?
Upvotes: 0
Views: 96
Reputation: 416
It's easy!
library(RCurl)
library(xml2)
html_inputs <- function(p, xpath = "//form/input") {
xml_find_all(p, xpath) %>% {setNames(as.list(xml_attr(., "value")), xml_attr(., "name"))}
}
get_header <- function(){
## RCurl设置, 直接把cookie粘贴过来,即可登录
myHttpheader<- c(
"User-Agent" = "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.71",
# "Accept" = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
"Accept-Language" = "zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3",
# "Accept-Encoding"="gzip, deflate",
"Connection"="keep-alive",
DNT = 1,
"Upgrade-Insecure-Requests" = 1,
"Host" = "www.geocaching.com")
file_cookie <- "cookies.txt"
ch <- getCurlHandle(# cainfo="pem/cacert.pem",
# ssl.verifyhost=FALSE, ssl.verifypeer = FALSE,
followlocation = TRUE,
verbose = TRUE,
cookiejar = file_cookie, cookiefile = file_cookie,
httpheader = myHttpheader)#带上百宝箱开始上路
tmp <- curlSetOpt(curl = ch)
return(ch)
}
ch <- get_header()
h <- basicHeaderGatherer()
#input your username and password here
user <- "kongdd"
pwd <- "****"
p <- getURL("https://www.geocaching.com/account/login", curl = ch)
tooken <- html_inputs(read_html(p))[1]
params <- list(Password = user,
Username = pwd) %>% c(., tooken)
p2 <- postForm("https://www.geocaching.com/account/login", curl = ch,
.params = params)
grep("kongdd", p2)#If 1 returned, it indicate you have login successfully.
After login successfully, you can access data with parameter curl
.
Upvotes: 1