diff --git a/selenium/README.md b/selenium/README.md new file mode 100644 index 00000000..a8b2615a --- /dev/null +++ b/selenium/README.md @@ -0,0 +1,196 @@ + + + + +WARNING +WARNING +WARNING +WARNING +WARNING + +

PLEASE NOTE: This document applies to the HEAD of the source tree

+ +If you are using a released version of Kubernetes, you should +refer to the docs that go with that version. + + +The latest 1.0.x release of this document can be found +[here](http://releases.k8s.io/release-1.0/examples/redis/README.md). +Documentation for other releases can be found at +[releases.k8s.io](http://releases.k8s.io). + +-- + + + + + +## Selenium on Kubernetes + +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. + +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: +``` +kubectl create --filename=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. +``` +kubectl create --filename=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: +``` +export NODEPORT=`kubectl get svc --selector='name=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}}"` + +curl http://$NODE:$NODEPORT +``` + +#### Kubernetes Nodes Unreachable +If you cannot reach your Kubernetes nodes from your network, you can proxy via kubectl. +``` +export PODNAME=`kubectl get pods --selector="name=selenium-hub" --output=template --template="{{with index .items 0}}{{.metadata.name}}{{end}}"` +kubectl port-forward --pod=$PODNAME 4444:4444 +``` + +In a seperate terminal, you can now check the status. +``` +curl http://localhost:4444 +``` + +#### Using Google Container Engine +If you are using Google Container Engine, you can expose your hub via the internet. This is a bad idea for many reasons, but you can do it as follows: +``` +kubectl expose rc selenium-hub --name=selenium-hub-external --labels="name=selenium-hub-external,external=true" --create-external-load-balancer=true +``` + +Then wait a few minutes, eventually your new `selenium-hub-external` service will be assigned an load balancing IP from gcloud. +``` +export INTERNET_IP=`kubectl get svc --selector="name=selenium-hub-external" --output=template --template="{{with index .items 0}}{{with index .status.loadBalancer.ingress 0}}{{.ip}}{{end}}{{end}}"` + +curl http://$INTERNET_IP:4444/ +``` + +### Deploy Firefox and Chrome Nodes: +Now that the Hub is up, we can deploy workers. + +This will deploy 3 Chrome nodes. +``` +kubectl create -f selenium-node-chrome-rc.yaml +``` + +And 3 Firefox nodes to match. +``` +kubectl create -f 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. +``` +kubectl run selenium-python --image=google/python-hello +``` + +Next, we need to get inside this container. +``` +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 +``` +pip install selenium +``` + +#### Run Selenium Job with Python +We're all set up, start the python interpreter. +``` +python +``` + +And paste in the contents of selenium-test.py. +```python +from selenium import webdriver +from selenium.webdriver.common.desired_capabilities import DesiredCapabilities + +def check_browser(browser): + driver = webdriver.Remote( + command_executor='http://selenium-hub:4444/wd/hub', + desired_capabilities=getattr(DesiredCapabilities, browser) + ) + driver.get("http://google.com") + assert "google" in driver.page_source + driver.close() + print("Browser %s checks out!" % browser) + + +check_browser("FIREFOX") +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: +``` +kubectl scale rc selenium-node-firefox --replicas=10 +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 password. Replace POD_NAME with the name of the pod you want to connect to. + +``` +kubectl port-forward --pod=POD_NAME 9000:5900 +``` + +Then connect to localhost:9000 with your VNC client using the password "secret" + +Enjoy your scalable Selenium Grid! + +Adapted from: https://github.com/SeleniumHQ/docker-selenium + +### Teardown + +To remove all created resources, run the following: + +``` +kubectl delete rc selenium-hub +kubectl delete rc selenium-node-chrome +kubectl delete rc selenium-node-firefox +kubectl delete rc selenium-python +kubectl delete svc selenium-hub +kubectl delete svc selenium-hub-external +``` diff --git a/selenium/selenium-hub-rc.yaml b/selenium/selenium-hub-rc.yaml new file mode 100644 index 00000000..b1d53361 --- /dev/null +++ b/selenium/selenium-hub-rc.yaml @@ -0,0 +1,36 @@ +apiVersion: v1 +kind: ReplicationController +metadata: + name: selenium-hub + labels: + name: selenium-hub +spec: + replicas: 1 + selector: + name: selenium-hub + template: + metadata: + labels: + name: selenium-hub + spec: + containers: + - name: selenium-hub + image: selenium/hub:2.47.1 + ports: + - containerPort: 4444 + resources: + limits: + memory: "1000Mi" + cpu: ".5" + livenessProbe: + httpGet: + path: /grid/console + port: 4444 + initialDelaySeconds: 30 + timeoutSeconds: 5 + readinessProbe: + httpGet: + path: /grid/console + port: 4444 + initialDelaySeconds: 30 + timeoutSeconds: 5 diff --git a/selenium/selenium-hub-svc.yaml b/selenium/selenium-hub-svc.yaml new file mode 100644 index 00000000..4feed038 --- /dev/null +++ b/selenium/selenium-hub-svc.yaml @@ -0,0 +1,15 @@ +apiVersion: v1 +kind: Service +metadata: + name: selenium-hub + labels: + name: selenium-hub +spec: + ports: + - port: 4444 + targetPort: 4444 + name: port0 + selector: + name: selenium-hub + type: NodePort + sessionAffinity: None diff --git a/selenium/selenium-node-chrome-rc.yaml b/selenium/selenium-node-chrome-rc.yaml new file mode 100644 index 00000000..6f78bdbe --- /dev/null +++ b/selenium/selenium-node-chrome-rc.yaml @@ -0,0 +1,29 @@ +apiVersion: v1 +kind: ReplicationController +metadata: + name: selenium-node-chrome + labels: + name: selenium-node-chrome +spec: + replicas: 2 + selector: + name: selenium-node-chrome + template: + metadata: + labels: + name: selenium-node-chrome + spec: + containers: + - name: selenium-node-chrome + image: selenium/node-chrome-debug:2.47.1 + ports: + - containerPort: 5900 + env: + - name: HUB_PORT_4444_TCP_ADDR + value: "selenium-hub" + - name: HUB_PORT_4444_TCP_PORT + value: "4444" + resources: + limits: + memory: "1000Mi" + cpu: ".5" diff --git a/selenium/selenium-node-firefox-rc.yaml b/selenium/selenium-node-firefox-rc.yaml new file mode 100644 index 00000000..c3496182 --- /dev/null +++ b/selenium/selenium-node-firefox-rc.yaml @@ -0,0 +1,29 @@ +apiVersion: v1 +kind: ReplicationController +metadata: + name: selenium-node-firefox + labels: + name: selenium-node-firefox +spec: + replicas: 2 + selector: + name: selenium-node-firefox + template: + metadata: + labels: + name: selenium-node-firefox + spec: + containers: + - name: selenium-node-firefox + image: selenium/node-firefox-debug:2.47.1 + ports: + - containerPort: 5900 + env: + - name: HUB_PORT_4444_TCP_ADDR + value: "selenium-hub" + - name: HUB_PORT_4444_TCP_PORT + value: "4444" + resources: + limits: + memory: "1000Mi" + cpu: ".5" diff --git a/selenium/selenium-test.py b/selenium/selenium-test.py new file mode 100644 index 00000000..bfaeeea7 --- /dev/null +++ b/selenium/selenium-test.py @@ -0,0 +1,17 @@ +from selenium import webdriver +from selenium.webdriver.common.desired_capabilities import DesiredCapabilities + +def check_browser(browser): + driver = webdriver.Remote( + command_executor='http://selenium-hub:4444/wd/hub', + desired_capabilities=getattr(DesiredCapabilities, browser) + ) + driver.get("http://google.com") + assert "google" in driver.page_source + driver.close() + print("Browser %s checks out!" % browser) + + +check_browser("FIREFOX") +check_browser("CHROME") +