Ran document cleanup script, changed flags to be consistent.

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Elson Rodriguez 2015-10-08 16:49:37 -07:00
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@ -20,7 +20,8 @@ refer to the docs that go with that version.
<strong>
The latest 1.0.x release of this document can be found
[here](http://releases.k8s.io/release-1.0/examples/redis/README.md).
[here](http://releases.k8s.io/release-1.0/examples/selenium/README.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
@ -35,28 +36,35 @@ Documentation for other releases can be found at
Selenium is a browser automation tool used primarily for testing web applications. However when Selenium is used in a CI pipeline to test applications, there is often contention around the use of Selenium resources. This example shows you how to deploy Selenium to Kubernetes in a scalable fashion.
### Prerequisites
This example assumes you have a working Kubernetes cluster and a properly configured kubectl client. See the [Getting Started Guides](../../docs/getting-started-guides/) for details.
This example assumes you have a working Kubernetes cluster and a properly configured kubectl client. See the [Getting Started Guides](../../docs/getting-started-guides/) for details.
Google Container Engine is also a quick way to get Kubernetes up and running: https://cloud.google.com/container-engine/
Your cluster must have 4 CPU and 6 GB of RAM to complete the example up to the scaling portion.
### Deploy Selenium Grid Hub:
We will be using Selenium Grid Hub to make our Selenium install scalable via a master/worker model. The Selenium Hub is the master, and the Selenium Nodes are the workers(not to be confused with Kubernetes nodes). We only need one hub, but we're using a replication controller to ensure that the hub is always running:
```console
kubectl create --filename=selenium-hub-rc.yaml
kubectl create --filename=examples/selenium/selenium-hub-rc.yaml
```
The Selenium Nodes will need to know how to get to the Hub, let's create a service for the nodes to connect to.
```console
kubectl create --filename=selenium-hub-svc.yaml
kubectl create --filename=examples/selenium/selenium-hub-svc.yaml
```
### Verify Selenium Hub Deployment
Let's verify our deployment of Selenium hub by connecting to the web console.
#### Kubernetes Nodes Reachable
If your Kubernetes nodes are reachable from your network, you can verify the hub by hitting it on the nodeport. You can retrieve the nodeport by typing `kubectl describe svc selenium-hub`, however the snippet below automates that by using kubectl's template functionality:
```console
export NODEPORT=`kubectl get svc --selector='app=selenium-hub' --output=template --template="{{ with index .items 0}}{{with index .spec.ports 0 }}{{.nodePort}}{{end}}{{end}}"`
export NODE=`kubectl get nodes --output=template --template="{{with index .items 0 }}{{.metadata.name}}{{end}}"`
@ -65,73 +73,91 @@ curl http://$NODE:$NODEPORT
```
#### Kubernetes Nodes Unreachable
If you cannot reach your Kubernetes nodes from your network, you can proxy via kubectl.
```console
export PODNAME=`kubectl get pods --selector="app=selenium-hub" --output=template --template="{{with index .items 0}}{{.metadata.name}}{{end}}"`
kubectl port-forward --pod=$PODNAME 4444:4444
```
In a seperate terminal, you can now check the status.
```console
curl http://localhost:4444
```
#### Using Google Container Engine
If you are using Google Container Engine, you can expose your hub via the internet. This is a bad idea for many reasons, but you can do it as follows:
```console
kubectl expose rc selenium-hub --name=selenium-hub-external --labels="app=selenium-hub,external=true" --create-external-load-balancer=true
```
Then wait a few minutes, eventually your new `selenium-hub-external` service will be assigned a load balanced IP from gcloud. Once `kubectl get svc selenium-hub-external` shows two IPs, run this snippet.
```console
export INTERNET_IP=`kubectl get svc --selector="app=selenium-hub,external=true" --output=template --template="{{with index .items 0}}{{with index .status.loadBalancer.ingress 0}}{{.ip}}{{end}}{{end}}"`
curl http://$INTERNET_IP:4444/
```
You should now be able to hit `$INTERNET_IP` via your web browser, and so can everyone else on the Internet!
### Deploy Firefox and Chrome Nodes:
Now that the Hub is up, we can deploy workers.
This will deploy 2 Chrome nodes.
```console
kubectl create -f selenium-node-chrome-rc.yaml
kubectl create --file=examples/selenium/selenium-node-chrome-rc.yaml
```
And 2 Firefox nodes to match.
```console
kubectl create -f selenium-node-firefox-rc.yaml
kubectl create --file=examples/selenium/selenium-node-firefox-rc.yaml
```
Once the pods start, you will see them show up in the Selenium Hub interface.
### Run a Selenium Job
Let's run a quick Selenium job to validate our setup.
#### Setup Python Environment
First, we need to start a python container that we can attach to.
```console
kubectl run selenium-python --image=google/python-hello
```
Next, we need to get inside this container.
```console
export PODNAME=`kubectl get pods --selector="run=selenium-python" --output=template --template="{{with index .items 0}}{{.metadata.name}}{{end}}"`
kubectl exec --stdin=true --tty=true $PODNAME bash
```
Once inside, we need to install the Selenium library
```console
pip install selenium
```
#### Run Selenium Job with Python
We're all set up, start the python interpreter.
```console
python
```
And paste in the contents of selenium-test.py.
```python
from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
@ -152,17 +178,20 @@ check_browser("CHROME")
```
You should get
```
>>> check_browser("FIREFOX")
Browser FIREFOX checks out!
>>> check_browser("CHROME")
Browser CHROME checks out!
```
Congratulations, your Selenium Hub is up, with Firefox and Chrome nodes!
### Scale your Firefox and Chrome nodes.
If you need more Firefox or Chrome nodes, your hardware is the limit:
```console
kubectl scale rc selenium-node-firefox --replicas=10
kubectl scale rc selenium-node-chrome --replicas=10
@ -171,8 +200,9 @@ kubectl scale rc selenium-node-chrome --replicas=10
You now have 10 Firefox and 10 Chrome nodes, happy Seleniuming!
### Debugging
Sometimes it is neccessary to check on a hung test. Each pod is running VNC. To check on one of the browser nodes via VNC, it's reccomended that you proxy, since we don't want to expose a service for every pod, and the containers have a weak VNC password. Replace POD_NAME with the name of the pod you want to connect to.
```console
kubectl port-forward --pod=POD_NAME 5900:5900
```
@ -195,3 +225,8 @@ kubectl delete rc selenium-python
kubectl delete svc selenium-hub
kubectl delete svc selenium-hub-external
```
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