can't execute rsDriver (connection refused)

Question

I can't get anywhere with R selenium. Here's the first step and my output:

library(RSelenium)
rD <- rsDriver()
# checking Selenium Server versions:
#   BEGIN: PREDOWNLOAD
# BEGIN: DOWNLOAD
# BEGIN: POSTDOWNLOAD
# checking chromedriver versions:
#   BEGIN: PREDOWNLOAD
# BEGIN: DOWNLOAD
# BEGIN: POSTDOWNLOAD
# checking geckodriver versions:
#   BEGIN: PREDOWNLOAD
# BEGIN: DOWNLOAD
# BEGIN: POSTDOWNLOAD
# checking phantomjs versions:
#   BEGIN: PREDOWNLOAD
# BEGIN: DOWNLOAD
# BEGIN: POSTDOWNLOAD
# [1] "Connecting to remote server"
# Error in checkError(res) : 
#   Undefined error in httr call. httr output: Failed to connect to localhost port 4567: Connection refused
# In addition: Warning message:
#   In rsDriver() : Could not determine server status.

What did I miss?

Answer 1

Note: this answer is meant for Windows

When trying to run the deprecated checkForServer() Selenium offers two options:

• use rsDriver
• use Docker

see:

RSelenium::checkForServer()
# Error: checkForServer is now defunct. Users in future can find the function in 
# file.path(find.package("RSelenium"), "examples/serverUtils"). The
# recommended way to run a selenium server is via Docker. Alternatively
# see the RSelenium::rsDriver function.

Everybody seems to have issues with rsDriver and Docker is the recommended option so we'll go this route:

• install docker
• run it, restart computer as requested
• pull image by running in command line: docker pull selenium/standalone-firefox (or chrome instead of firefox ) or in R shell('docker pull selenium/standalone-firefox')
• start server by running in command line: docker run -d -p 4445:4444 selenium/standalone-firefox or in R shell('docker run -d -p 4445:4444 selenium/standalone-firefox')
• Then run remDr <- remoteDriver(remoteServerAddr = "localhost", port = 4445L, browserName = "firefox'") . The doc suggests something different with a virtual machine but i couldn't get it to work.

With this I was set, here is my code:

shell('docker run -d -p 4445:4444 selenium/standalone-firefox')
remDr <- remoteDriver(remoteServerAddr = "localhost", port = 4445L, browserName = "firefox")
remDr$open()
remDr$navigate("http://www.google.com/ncr")
remDr$getTitle()
# [[1]]
# [1] "Google" 

The doc for more info:

• https://cran.r-project.org/web/packages/RSelenium/vignettes/RSelenium-basics.html
• https://cran.r-project.org/web/packages/RSelenium/vignettes/RSelenium-docker.html

Answer 2

In case that is still useful, I was running into the same problem today and was able to fix it by installing a Java Development Kit (Java SE Development Kit 11.0.1).

I was getting an error message from my computer to that effect, as well as the same R error as mentioned in this question, and it fixed it.

For a reproducible example, I was able to replicate this tutorial .

sessionInfo() R version 3.4.4 (2018-03-15) Platform: x86_64-apple-darwin15.6.0 (64-bit) Running under: macOS High Sierra 10.13.5

Matrix products: default
BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRlapack.dylib

locale:
[1] fr_CA.UTF-8/fr_CA.UTF-8/fr_CA.UTF-8/C/fr_CA.UTF-8/fr_CA.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] RSelenium_1.7.5

loaded via a namespace (and not attached):
[1] Rcpp_0.12.17     XML_3.98-1.11    binman_0.1.1     assertthat_0.2.0 rappdirs_0.3.1   bitops_1.0-6    
[7] R6_2.2.2         jsonlite_1.5     semver_0.2.0     httr_1.3.1       curl_3.2         xml2_1.2.0      
[13] subprocess_0.8.3 tools_3.4.4      wdman_0.2.4      yaml_2.1.18      compiler_3.4.4   caTools_1.17.1  
[19] openssl_1.0.1 

Answer 3

After using RSelenium/rsDriver for a while without issue, I recently got a very similar error message as OP, but couldn't use Docker to solve it (mostly for organizational reasons). Here's how I solved it:

Taking a look at the function documentation , it turns out that rsDriver() is default configured to launch the Selenium server with the latest versions of both Chrome and Firefox (Gecko) drivers, even if you have specified the other browser to run. In my case, I was specifying browser = "firefox" , but a new Chrome driver had auto-downloaded on the most recent run and, for whatever reason, wasn't playing nice with Selenium. That was the root cause of the issue.

It's not particularly intuitive, and the "Connection refused" message doesn't really help, but following the error advice and checking the server log made me realize that Selenium was still trying to load Chrome drivers, even though I was using Firefox:

rd <- rsDriver(browser = "firefox")
# Yields an error message after doing pre/post downloads:

#> Could not open firefox browser.
#> Client error message:
#> Undefined error in httr call. httr output: Failed to connect to localhost port 4567: Connection refused
#> Check server log for further details.
#> Warning message:
#> In rsDriver(browser = "firefox" :
#>  Could not determine server status.

rd$server$log()

> $stderr
> [1] "Error: Could not find or load main class c(-Dwebdriver.chrome.driver=\"C:\filepath\to\chromedrivers\109.0.5414.25.chromedriver.exe\","

> $stdout
> character(0)

Anyway, if you specify rsDriver() to run with either an older driver version, or just pass in NULL so it doesn't look for a driver at all, it might fix the issue (it worked for me).

# Default parameters of the rsDriver() function:

rsDriver(port = 4567L,
         browser = c("chrome", "firefox", "phantomjs", "internet explorer"),
         version = "latest",
         chromever = "latest",
         geckover = "latest",
         iedrver = NULL,
         phantomver = "2.1.1",
         verbose = TRUE,
         check = TRUE,
         ...)

# Specify an older driver version you know works (or just use NULL), 
# even if it doesn't correspond to the browser you're using:

rd <- rsDriver(broswer = "firefox",
               chromever = "109.0.5414.25") # alt: chromever = NULL

In case you're looking for the filepath that these drivers get saved to when auto-downloaded by RSelenium (eg maybe you want to find the name of an older driver version), on Windows, it should be ~/AppData/Local/binman .

Shoutout to the responses on this question , which also helped point me in the right direction!

Answer 4

Per the Cran vignette I had to run:

shell("docker-machine ip")

Then set the remoteServerAddr to the IP which was returned.