Most Git repository servers support the concept of web hooks — calling to an external source via HTTP(S) when a change in the code repository happens. OpenShift provides an API endpoint that supports receiving hooks from remote systems in order to trigger builds. By pointing the code repository’s hook at the OpenShift API, automated code/build/deploy pipelines can be achieved.
{% if GIT_HOST == "github" %} ## Getting the webhook URL
Go to Builds → Builds → Configuration and there in the Triggers section there is Github webhook URL copy the URL to be used for configuring the webhook at Github.
Open the Github repository page and go to the Settings tab and then to Webhooks in the left menu. Click Add webhook and fill the form
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Payload URL is the URL copied from OpenShift
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Content type has to be application/json
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Secret should be empty
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Disable SSL verification as the cluster does not have valid SSL certificates
And click the Add webhook button.
Go back to the Code tab in the same repository and open the wsgi.py file. Click the pen icon in the top right corner to edit the file.
Go to the line 35 and change the displayName.
Scroll down to the bottom of the page and click Commit changes.
{% if modules.pipelines %}
In previous labs, you created a CI/CD Pipeline to automate build, test and deployment of
the nationalparks application. In this lab you can use the pipline webhook to
trigger a pipeline execution every time there is a change in the nationalparks GitLab
repository. In the OpenShift web console, navigate to your {{EXPLORE_PROJECT_NAME}}{{USER_SUFFIX}} Project, and
then mouse-over Browse and then Pipelines. Click the nationalparks-pipeline and
then Configuration tab.
On this screen you will see the option to copy the generic webhook URL as shown in the following image:
{% else %}
In the OpenShift web console, navigate to your {{EXPLORE_PROJECT_NAME}}{{USER_SUFFIX}} Project, and
then mouse-over Browse and then Builds. Click the nationalparks build.
On this screen you will see the option to copy the generic webhook URL as shown in the following image:
{% endif %}
Once you have the URL copied to your clipboard, navigate to the code repository that you have on your local GitLab:
{% if PARKSMAP_PY %}
http://{{GITLAB_URL_PREFIX}}.{{ROUTER_ADDRESS}}/{{GITLAB_USER}}/nationalparks-py/tree/{{NATIONALPARKS_VERSION}}
{% else %}
http://{{GITLAB_URL_PREFIX}}.{{ROUTER_ADDRESS}}/{{GITLAB_USER}}/nationalparks
{% endif %}|
Note
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The credentials for this GitLab instance are: Username: {{GITLAB_USER}} Password: {{GITLAB_PASSWORD}} |
Click the Settings link on the top right of the screen, and then click "Integrations":
In the next screen, paste your link into the "URL" field. You can leave the secret token field blank — the secret is already in the URL and does not need to be in the payload.
Scroll to the bottom of the page. Make sure you un-check the SSL verification box. Remember that OpenShift’s API is not presenting an SSL certificate signed by a known/trusted authority. Without un-checking the verification box, the webhook will fail.
Finally, click on "Add webhook".
Boom! From now on, every time you commit new source code to your GitLab repository, a new build and deploy will occur inside of OpenShift. Let’s try this out.
{% if PARKSMAP_PY %} Be sure you return to the proper tag in the git repository:
Click "Project" at the top of the GitLab page, and then "Files" towards the
middle of the page. This is GitLab’s repository view. Make sure that the
drop-down menu at the upper right is set for the 1.0.0 branch. Navigate to the
root path and click on the wsgi.py file.
Once you have the file on the screen, click the edit button in the top right hand corner as shown here:
Change line number 35:
'displayName': 'National Parks (PY)'To
'displayName': 'World National Parks (PY)'{% else %}
Click "Project" at the top of the GitLab page, and then "Files" towards the
middle of the page. This is GitLab’s repository view. Make sure that the
drop-down menu at the upper right is set for the {{NATIONALPARKS_VERSION}} branch. Navigate to the
following path:
src/main/java/com/openshift/evg/roadshow/parks/rest/Then click on the BackendController.java file.
Once you have the file on the screen, click the edit button in the top right hand corner as shown here:
Change line number 20:
return new Backend("nationalparks","National Parks", new Coordinates("47.039304", "14.505178"), 4);To
return new Backend("nationalparks","OpenShift National Parks", new Coordinates("47.039304", "14.505178"), 4);{% endif %}
Click on Commit changes at the bottom of the screen. Feel free to enter a commit message.
{% endif %}
{% if modules.pipelines %}
Once you have committed your changes, the nationalparks-pipeline should almost
instantaneously be triggered in OpenShift. Look at the Builds → Pipelines
page in OpenShift Console to verify the pipeline is running:
After the test stage, pipeline waits for manual approval in order to deploy to the Live container. Click on Input Required link which takes you to the Jenkins Console for approving the deployment and then Proceed button.
Once the pipeline execution is finished, verify your new Docker image was automatically deployed by viewing the application in your browser:
{% else %} Once you have committed your changes, a Build should almost instantaneously be triggered in OpenShift. Look at the Builds page in the web console, or run the following command to verify:
$ oc get buildsYou should see that a new build is running:
NAME TYPE FROM STATUS STARTED DURATION
nationalparks-1 Source Git@b052ae6 Complete 18 hours ago 36s
nationalparks-2 Source Git@3b26e1a Running 43 seconds agoOnce the build and deploy has finished, verify your new Docker image was automatically deployed by viewing the application in your browser: {% endif %}
http://nationalparks{% if modules.pipelines %}-live{% endif %}-{{EXPLORE_PROJECT_NAME}}{{USER_SUFFIX}}.{{ROUTER_ADDRESS}}/ws/info/You should now see the new name you have set in the JSON string returned.
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Note
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To see this in the map’s legend itself, you will need to scale down your parksmap to 0, then back up to 1 to force the app to refresh its cache. |
OpenShift allows you to move between different versions of an application
without the need to rebuild each time. Every version (past builds) of the
application exists as a Docker-formatted image in the OpenShift registry. Using
the oc rollback and oc deploy commands you can move back- or forward between
various versions of applications.
In order to perform a rollback, you need to know the name of the Deployment Config which has deployed the application:
$ oc get dcThe output will be similar to the following:
NAME REVISION DESIRED CURRENT TRIGGERED BY
mongodb 1 1 1 config,image(mongodb:3.2)
parksmap 2 1 1 config,image(parksmap:{{PARKSMAP_VERSION}})
nationalparks 9 1 1 {% if modules.pipelines %}config{% else %}config,image(nationalparks:latest){% endif %}
{% if modules.pipelines %}
jenkins 1 1 1 config,image(jenkins:latest)
mongodb-live 1 1 1 config,image(mongodb:3.2)
nationalparks-live 4 1 1 config,image(nationalparks:live)
{% endif %}Now run the following command to rollback the latest code change:
$ oc rollback nationalparks{% if modules.pipelines %}-live{% endif %}You will see output like the following:
#5 rolled back to nationalparks{% if modules.pipelines %}-live{% endif %}-3
Warning: the following images triggers were disabled: nationalparks:live
You can re-enable them with: oc set triggers dc/nationalparks{% if modules.pipelines %}-live{% endif %} --autoOnce the deploy is complete, verify that the page header is reverted to the original header by viewing the application in your browser.
http://nationalparks{% if modules.pipelines %}-live{% endif %}-{{EXPLORE_PROJECT_NAME}}{{USER_SUFFIX}}.{{ROUTER_ADDRESS}}/ws/info/|
Note
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Automatic deployment of new images is disabled as part of the rollback to prevent unwanted deployments soon after the rollback is complete. To re-enable the automatic deployments run this: |
Just like you performed a rollback, you can also perform a roll-forward using the same command. You’ll notice above that when you requested a rollback, it caused a new deployment (#3). In essence, we always move forwards in OpenShift, even if we are going "back".
{% if modules.pipelines %} * We know that the first deployment (#1) was the initial definition. * We know that the second deployment (#2) was due to our configmap addition. * We know that the third deployment (#3) was our first run of the pipeline. * We know that the fourth deployment (#4) was our change to "OpenShift National Parks". * We know that the fifth deployment (#5) was our rollback to "National Parks". {% endif %}
So, if we want to return to the "new code" version, that is deployment #4.
$ oc rollback nationalparks{% if modules.pipelines %}-live{% endif %}-4And you will see the following:
#6 rolled back to nationalparks{% if modules.pipelines %}-live{% endif %}-4
Warning: the following images triggers were disabled: nationalparks:live
You can re-enable them with: oc set triggers dc/nationalparks{% if modules.pipelines %}-live{% endif %} --autoCool! Once the rollback is complete, verify you again see "OpenShift National Parks".