xvfb-run hanging on server - selenium

On our build server (bamboo launched) we are wanting to do selenium tests, to do this we are running xvfb-run, this works on our local servers which are all of the same type.
If I log on to the build server and run:
xvfb-run echo 'i'
I get the error:
xvfb-run: error: Xvfb failed to start
I have tried running like this:
xvfb-run -a echo 'i'
This time it just hangs and never finishes, any ideas on things I can try?
Thanks

Run following commands:
sudo nohup Xvfb :40 -ac &
export DISPLAY=:40

Since it works locally, I suspect a server or permissions issue is going on. Perhaps your user can't open up a lock file in /tmp ? Try to get more info about the problem by running:
xvfb-run -e /dev/stdout [mycommand]

Related

Gitlab CI job failed: ERROR the input device is not a TTY

I've registered a GitLab Runner with shell executor installed on Ubuntu 18.04, and also set up a docker container with the command below
docker run -it --gpus '"device=0"' --net=host -v /home/autotest/Desktop/ai_platform:/app --name=ai_platform_system nvcr.io/nvidia/pytorch:20.10-py3 "bash"
Then I tried to execute the following command from the gitlab-ci.yml in Gitlab CI, but I got an error "The input device is not a TTY".
docker attach ai_platform_system
Any clues for this issue except using docker exec? I know docker exec works in Gitlab CI environment but it will create a new session in the container which is not desirable for me. Thanks!
According to this answer (for Jenkins but the same problem) you need to remove the -it flag and the tty.
docker run -T --gpus '"device=0"' --net=host -v /home/autotest/Desktop/ai_platform:/app --name=ai_platform_system nvcr.io/nvidia/pytorch:20.10-py3 "bash"

WebDriverException: Message: invalid argument: can't kill an exited process in a Docker container returns odd errors

I'm running a small Python script that scrapes some data from a public website.
When I run the Dockerfile instructions line by line in an interactive terminal using the selenium:latest image the script runs fine.
docker run -it -v /Users/me/Desktop/code/scraper/:/scraper selenium/standalone-firefox bash
As soon as I run it using my Dockerfile and docker-compose file I get this error:
app_1 | selenium.common.exceptions.WebDriverException: Message: invalid argument: can't kill an exited process
I am using the MOZ_HEADLESS=1 env var. It's being passed properly.
I have tried running the script as someone other than root but then I get log errors.
Dockerfile
FROM selenium/standalone-firefox:latest
# https://github.com/SeleniumHQ/docker-selenium/issues/725
USER root
RUN apt-get update -y
RUN apt-get install -y firefox python-pip
WORKDIR /scraper
COPY . /scraper
RUN pip install -r /scraper/requirements.txt
ENV MOZ_HEADLESS=1
CMD ["python", "/scraper/browserscraper.py"]
If I run those instructions in the Dockerfile from an interactive terminal, I have no problems.
It either has to do with the user being root running the script via the Dockerfile or something about it missing a screen for output because I'm not actually SSH'ed in like I am running it from the command line with -it.
Any ideas?

Docker command won't work unless I open an interactive bash terminal

I'm using Docker to running automated browser testing using nightwatch.js
When I open an interactive terminal it works fine, e.g.
docker run -it --rm username/image-name /bin/bash
that gives me a bash prompt and I run:
xvfb-run node nightwatch.js
and everything works fine.
But when I run:
docker run --rm username/image-name xvfb-run node nightwatch.js
It just hangs.
What's the difference between opening a bash terminal and manually running the test command, and just running the test command directly? Surely they should both work?
Ok so I still don't know what is causing this issue, but I have a workaround that works quite well:
Run bash as a daemon:
CONTAINERID=$(docker run -it -d username/image-name /bin/bash)
Then use docker exec:
docker exec $CONTAINERID xvfb-run node nightwatch.js
Of course you will need to do some tidying up afterwards:
docker stop $CONTAINERID
docker rm $CONTAINERID

"docker run -dti" with a dumb terminal

updated: added the missing docker attach.
Hi am trying to run a docker container, with -dti. but I cannot access with a terminal set to dumb. is there a way to change this (it is currently set to xterm, even though my ssh client is dumb)
example:
create the container
docker run -dti --name test -v /my-folder alpine /bin/ash
docker attach test
apk --update add nodejs
cd /my-folder
npm install -g gulp
the last command always contains ascii escape chars to move the cursor.
I have tried "export TERM=dumb" inside the running container, but it does not work.
is there a way to "run" this using the dumb terminal?
I am running this from a script on another computer, via (dumb) ssh.
using the -t which sets this https://docs.docker.com/engine/reference/run/#env-environment-variables, however removing effects the command prompt (the prompt is not shown)
possible solution 1 remove the -t and keep the -i. To see if the command has completed echo out a known token (ENDENDEND). ie
docker run -di --name test -v /my-folder alpine /bin/ash
docker attach test
apk --update add nodejs;echo ENDENDEND
cd /my-folder;echo ENDENDEND
npm install -g gulp;echo ENDENDEND
not pretty, but it works (there is no ascii in the results)
Possible solution 2 use the journal, docker can log out to the linux journal, this can be gathered as commands are executed in the container. (I have yet to fully test this one out. however the log seems to be a nicer output of what happened)
update:
Yep -t is the problem.
However if you want to see the entire process when running a command, maybe this way is better:
docker run -di --name test -v/my-folder alpine /bin/ash
docker exec -it test /bin/ash
finally you need to kill the container after all jobs finished.
docker run -d means "Run container in background and print container ID"
not start the container as a daemon
I was hitting this issue on OSx running docker, i had to do 2 things to stop the terminal/ascii/ansi escape sequences.
remove the "t" option on the docker run command (from docker run -it ... to docker run -i...)
ensure to force bash or sh shells used on osx when running the command from a script file, not the default zsh
Also
the escape sequences were not always visible on the terminal
even so, they still usually caused content corruption, even with SED brought to bear
they always were shown in my editor

Selenium Server on startup

I'm using Selenium RC in a Ubuntu system.
I want to automate the tests, and I need to start Selenium-server.jar on startup of the machine.
I created seleniumServer.conf in /ect/init/ with:
start on startup
start on runlevel 3
respawn
exec xvfb-run java -jar /home/condde/selenium-server-1.0.3/selenium-server.jar -port 4444
When I reboot the machine, it works fine, the process is running.
But when I execute a test, the result is:
PHPUnit_Framework_Exception: Could not connect to the Selenium RC server.
Any ideas?
Thanks!
I have the same problem, my process can not connect the selenium server sometimes. After dig into debug log and selenium source code, I found that's because java's SecureRandom hangs if /dev/random hangs when selenium try generate random number. So I replace /dev/random with /dev/urandom, then selenium server works fine:
sudo mv /dev/random /dev/random.real
sudo ln -s /dev/urandom /dev/random
Or you can modify $JAVA_HOME/jre/lib/security/java.security file and changing the property:
securerandom.source=file:/dev/random
to:
securerandom.source=file:/dev/urandom
Maybe it works, but not for me.
Use -debug to start Selenium with debug log to see if any error.
java -jar selenium-server.jar -debug > /var/log/selenium-server.log 2>&1
I did this on ubuntu 14 using npm.
First, install the selenium-standalone via npm.
sudo npm install selenium-standalone -g
sudo selenium-standalone install
Then create a symbolic link in /etc/init.d, and configure it to run.
sudo ln -s /usr/local/bin/selenium-standalone /etc/init.d/
sudo update-rc.d selenium-standalone defaults
Another very simple and good solution is to install selenium via docker. I have used the chrome image and it's easy as:
sudo docker run -d -p 4444:4444 selenium/standalone-chrome
The -d option makes is a daemon that will be restarted every time you start your computer. The -p option forwards the webdriver port (4444) from the docker instance to the host.
Well, it's not phantomjs, but I like chrome better anyway. There is also a firefox image! Checkout https://github.com/SeleniumHQ/docker-selenium for more info.
I would start the selenium server process with -log parameter to get info from the process first and all and see if it actually get any kind of connections, errors etc..
A few ideas to troubleshoot:
Do you get any response if you enter http://localhost:4444
It should render a 403 error by the Jetty engine.
If this does not work I would try with your actual IP:4444, that might indicate problem with localhost variable, proxy settings etc..
Could the firewall settings be blocking the the 4444 port? Maybe the Selenium Server process is not allowed to start the browser.