CODEWITHSUNDEEP
rssl
nm200
nm200

Reputation: 336

R and Peer certificate cannot be authenticated with given CA certificates

I am trying to read a webpage and am getting the error message that the certificate can not be authenticated. My code is:

qurl<-"https://www.chemspider.com/Chemical-Structure.1.html" h <- try(read_html(qurl), silent = TRUE)

I can access the webpage no worries directly in my browser and I have tried

library(httr) set_config(config(ssl_verifypeer = 0L))

(also ssl.verifypeer - I read somewhere that was an older version), but I am still getting the error message:

Peer certificate cannot be authenticated with given CA certificates

I have also tried re-installing curl and even R, but without success. I am using R3.4.0 (3.3.3 before re-installing). Any ideas how I can read this webpage)

Upvotes: 1

Views: 2731

Answers (2)

T.Donaldson
T.Donaldson

Reputation: 115

I had the same problem with Amazon Linux on an EC2 instance.

I eventually, having tried every suggestion I could find, resorted to:

library(RCurl)
webpage <- getURL("https://sourceforge.net/", .opts=list(followlocation=TRUE, ssl.verifyhost=FALSE, ssl.verifypeer=FALSE))

Upvotes: 2

user2067434
user2067434

Reputation: 1

R version 3.3.3 produced the following:

install.packages("rvest")
library(rvest)
qurl<-"https://www.chemspider.com/Chemical-Structure.1.html"
h <- try(read_html(qurl), silent = TRUE)
h

{xml_document}
<html xmlns="http://www.w3.org/1999/xhtml">
[1] <head id="ctl00_ctl00_Head1">\n<meta http-equiv="Content-Type" 
content="text/html; charset=UTF-8">\n<link rel="shortcut icon" href=" ...
[2] <body id="ctl00_ctl00_chemspider_body" class="rsc-ui">\r\n    <form 
name="aspnetForm" method="post" action="/Chemical-Structure.1.ht ...

Upvotes: 0

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