maxprime

UI and REST service demo calculating highest prime number up to the number specified by the user. Good for infrastructure scaling demo

Note, this app is also used to demonstrate GitOps on Knative using Cloud Build. See the GitOps section below

Demo

Live version of this app is available at https://maxprime.demo.knative.tech

Request

To calculate the highest prime number in UI

curl http://localhost:8080

You can also pass max number using REST service

curl http://localhost:8080/prime/5000000

Response

prime.val in the response has the highest prime number bellow passed in argument.

{
    "id": "0fe3fa30-627e-46cc-be09-a9de62252ff1",
    "ts": "2019-03-24 13:54:14.917105 +0000 UTC",
    "dur": "724.848232ms",
    "rel": "v0.0.1",
    "prime": {
        "max": 50000340,
        "val": 50000329
    }
}

GitOps

Simple setup to automate Knative deployments using Git and Cloud Build

As a developer, you write code and commit it to a git repo. You also hopefully run tests on that code for each commit. Assuming your application passes all the tests, you may want to deploy it to Knative cluster. You can do it form your workstation by using any one of the Knative CLIs (e.g. gcloud, knctl, tm etc.).

In this demo however we are going to demonstrate deploying directly from git repository. This means that you as a developer do not need install anything on your machine other than the standard git tooling. Here is the outline:

Create a release tag on the commit you want to deploy in git
Cloud Build then:
- Tests (again)
- Builds and tags image
- Pushes that image to repository
- Creates Knative service manifest
- Applies that manifest to designated Knative cluster

As an add-on, we are also going to send mobile notification with build status using knative-build-status-notifs

Setup

You will have to configure git trigger in Cloud Build first. There doesn't seem to be a way to do this using gcloud.

Then setup IAM policy binding to allow Cloud Builder deploy build image to your cluster

PROJECT_NUMBER="$(gcloud projects describe ${PROJECT_ID} --format='get(projectNumber)')"
gcloud projects add-iam-policy-binding ${PROJECT_NUMBER} \
    --member=serviceAccount:${PROJECT_NUMBER}@cloudbuild.gserviceaccount.com \
    --role=roles/container.developer

Finally submit the Cloud Build configuration

gcloud builds submit --config deployments/build.yaml

Deployment

To build and deploy specific commit from git, tag it and publish the tags. We also are going to print the last few tags so we can see the exact commit hash.

git tag "release-v${RELEASE_VERSION}"
git push origin "release-v${RELEASE_VERSION}"
git log --oneline

Logs

You can monitor progress of your build but first finding its id

gcloud builds list

And then describing it

gcloud builds describe BUILD_ID

You can always also navigate to the Build History screen in UI and see it there.

Load

First forward Knative Monitoring (Grafan) to a local port (3000)

kubectl port-forward -n knative-monitoring \
    $(kubectl get pods -n knative-monitoring --selector=app=grafana \
    --output=jsonpath="{.items..metadata.name}") 3000

Now you can view the Knative revision dashboard here

You can also view the maxprime pods beign scaled here

watch kubectl get pods -n demo -l serving.knative.dev/service=maxprime

And finally, to generate some load, run the included load generator. --count is the number of concurrent client (threads), --prime is the max number to calculate prime for, and --url is the target URL where maxprime demo is deployed (no final slash).

go run load/main.go --count 300 --prime 99999 \
    --url https://maxprime.demo.knative.tech

vagababov/maxprime