status code 400 (Selenium::WebDriver::Error::ServerError) - selenium-webdriver

Question

This error:
status code 400 (Selenium::WebDriver::Error::ServerError)
is displayed after my test fails on a step where I have pasted input to a field. The test started to fail after I updated Selenium WebDriver to 3.6.0 and Firefox to 56.0.
I'm using Ruby - Capybara - Cucumber. What's the reason of a failure and how can I fix it?

Answer 1

upgrade your geckodriver
macOS:
brew install geckodriver
I hope it helps you.

Answer 2

I had the same issue on my deploy ubuntu server.
I installed geckodriver with this script
Before running run this
sudo apt-get install jq
install_dir="/usr/local/bin"
json=$(curl -s https://api.github.com/repos/mozilla/geckodriver/releases/latest)
if [[ $(uname) == "Darwin" ]]; then
url=$(echo "$json" | jq -r '.assets[].browser_download_url | select(contains("macos"))')
elif [[ $(uname) == "Linux" ]]; then
url=$(echo "$json" | jq -r '.assets[].browser_download_url | select(contains("linux64"))')
else
echo "can't determine OS"
exit 1
fi
curl -s -L "$url" | tar -xz
chmod +x geckodriver
sudo mv geckodriver "$install_dir"
echo "installed geckodriver binary in $install_dir"
Available on github.gist
It downloads latest bin version for geckodriver from official repo.
But it didn't help me. After many hours of investigation what is wrong I came across very strange issue.
geckodriver -v in my $HOME directory returned 0.19.1 version
But when I go to my deployed project path by capistrano.
cd ~/apps/app_name/production/current
geckodriver -v
=> 0.14.1
which geckodriver
=> /home/$USER/.rvm/bin/geckodriver
rm -rf /home/$USER/.rvm/bin/geckodriver
=> geckodriver -v
0.19.1
So I have first to delete .rvm default version for project, and then my global geckodriver version became available for application.