--- parser: v2 auto_validation: true time: 25 tags: [ tutorial>beginner, programming-tool>node-js] primary_tag: software-product>sap-btp\, kyma-runtime slug: deploy-nodejs-application-kyma canonical_url: https://developers.sap.com/tutorials/deploy-nodejs-application-kyma --- # Deploy a Node.js Application in SAP BTP, Kyma runtime Build a basic Node.js application into OCI image and push it into Docker registry. Besides, describe the corresponding Kubernetes objects for the application. Based on the above, deploy the application into SAP BTP, Kyma runtime. ## Prerequisites - You have a Kyma runtime environment on SAP Business Technology Platform (BTP) and the relevant command line tools. If not, please follow the tutorials [Enable SAP BTP, Kyma runtime](cp-kyma-getting-started) and [Install the Kubernetes Command Line Tool](cp-kyma-download-cli). - You have installed [Docker](https://docs.docker.com/get-started/#download-and-install-docker). - You have [Docker Hub](https://hub.docker.com/) account. - You have finished the tutorial [Create a Basic Node.js Application with Express Generator](basic-nodejs-application-create). ## You will learn - How to build Application to OCI Image - How to push OCI image to Docker Hub - How to describe Kubernetes objects for web application - How to deploy application into Kyma runtime --- ### Determine SAP BTP Subaccount Subdomain Open your subaccount in SAP BTP cockpit. Make sure you've already enabled SAP BTP, Kyma runtime on your cluster. ### Build Application as OCI Image In order to run your code on Kyma Runtime (or on any Kubernetes-based platform), you need to provide an OCI image (aka Docker image) for your application. While you are in principle free to choose your image building tool, we recommend using [Cloud Native Buildpacks (CNB)](https://buildpacks.io/). The command-line tool `pack` supports providing a buildpack and your local source code and creating an OCI image from it. We are working on a process to provide recommended and supported buildpacks. In the meantime, you can use the community-supported [Paketo Buildpacks](https://paketo.io/). **1.** Install command-line tool `pack`: [Install Pack](https://buildpacks.io/docs/tools/pack/) For example (macOS): ```Shell / Bash brew install buildpacks/tap/pack ``` When we speak about repository name, we mean the combination of account and repo name that is usual with Docker Hub: `/`. An example would be `tiaxu/multitenant-kyma-backend`. As you can only create one private repository in a free Docker hub account, Docker images stored in Docker hub will have different tag names so that they can be stored under one repository. Thus, addressing an image will include the tag name:`/:`. An example would be `tiaxu/multitenant-kyma-backend:v1`. **2.** In the directory `kyma-multitenant-node`, build the image for the approuter app from source, for example: ```Shell / Bash pack build /multitenant-kyma-backend:v1 --builder paketobuildpacks/builder-jammy-full ``` ### Push OCI Image to Docker Hub **1.** Log in to Docker using this command: ```Shell / Bash docker login -u -p ``` **2.** Push the local image into the Docker Hub: ```Shell / Bash docker push /multitenant-kyma-backend:v1 ``` > For more details, see the [Kubernetes documentation](https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/). ### Create Namespace Then you are ready to deploy it into the Kubernetes cluster with Kyma runtime. **1.** Select the `Link to dashboard` to open Kyma dashboard. ![image-20220112154735200](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/deploy-nodejs-application-kyma/image-20220112154735200.png) **2.** Create a new namespace through Kyma dashboard or `kubectl` CLI, for example, called `multitenancy-ns`: ![create_namespace](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/deploy-nodejs-application-kyma/create_namespace.png) **3.** Enable Istio Sidecar Proxy Injection Enabling Istio sidecar proxy injection for a namespace allows istiod to watch all Pod creation operations in this namespace and automatically inject newly created Pods with an Istio sidecar proxy. Switch the toggle to enable Istio sidecar proxy injection. Click `Create` to finish namespace creation. ![enable_ns_sidecar](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/deploy-nodejs-application-kyma/enable_ns_sidecar.png) > For more details, refer to the [Enable Istio Sidecar Proxy Injection](https://kyma-project.io/#/istio/user/tutorials/01-40-enable-sidecar-injection?id=enable-sidecar-injection-for-a-namespace) ### Deploy Secret for Docker Hub Since the OCI image is stored in your Docker hub, you need to provide the access information to your Kyma cluster that you can pull the images from those repositories, replace the placeholder values according to your account: ```Shell / Bash kubectl -n multitenancy-ns create secret docker-registry registry-secret --docker-server=https://index.docker.io/v1/ --docker-username= --docker-password= --docker-email= ``` Therefore, all deployment files contain an `imagePullSecret` entry, which should be set to `registry-secret`. ```yaml imagePullSecrets: - name: registry-secret # replace with your own registry secret ``` ### Prepare Deployment Description File Based on the previous preparation steps, you can define the description file for deployment. In the root directory `multitenancy-kyma-tutorial`, create a new YAML file called `k8s-deployment-backend.yaml` with the following content: ```yaml --- apiVersion: gateway.kyma-project.io/v2 kind: APIRule metadata: labels: app: kyma-multitenant-node-multitenancy release: multitenancy name: kyma-multitenant-node-multitenancy spec: gateway: kyma-system/kyma-gateway hosts: - kyma-multitenant-node-multitenancy rules: - path: /* methods: ["GET", "POST", "PUT", "PATCH", "DELETE", "HEAD"] noAuth: true service: name: kyma-multitenant-node-multitenancy port: 8080 --- apiVersion: apps/v1 kind: Deployment metadata: labels: app: kyma-multitenant-node-multitenancy release: multitenancy name: kyma-multitenant-node-multitenancy spec: replicas: 1 selector: matchLabels: app: kyma-multitenant-node-multitenancy release: multitenancy template: metadata: labels: app: kyma-multitenant-node-multitenancy release: multitenancy sidecar.istio.io/inject: "true" # Enable Istio sidecar injection on Deployment and all Pods spec: imagePullSecrets: - name: registry-secret # replace with your own registry secret containers: - env: - name: PORT value: "8080" - name: TMPDIR value: /tmp - name: BP_NODE_OPTIMIZE_MEMORY value: "false" image: /multitenant-kyma-backend:v1 # replace with your Docker Hub account name name: kyma-multitenant-node-multitenancy ports: - name: http containerPort: 8080 protocol: TCP livenessProbe: httpGet: path: / port: http readinessProbe: httpGet: path: / port: http startupProbe: httpGet: path: / port: http failureThreshold: 15 periodSeconds: 2 resources: limits: cpu: 100m memory: 256M requests: cpu: 100m memory: 256M securityContext: allowPrivilegeEscalation: false capabilities: drop: - ALL privileged: false runAsNonRoot: true readOnlyRootFilesystem: false volumeMounts: - mountPath: /tmp name: tmp volumes: - emptyDir: {} name: tmp --- apiVersion: v1 kind: Service metadata: creationTimestamp: null labels: app: kyma-multitenant-node-multitenancy release: multitenancy name: kyma-multitenant-node-multitenancy spec: ports: - port: 8080 protocol: TCP targetPort: 8080 selector: app: kyma-multitenant-node-multitenancy release: multitenancy status: loadBalancer: {} --- apiVersion: networking.k8s.io/v1 kind: NetworkPolicy metadata: creationTimestamp: null labels: release: multitenancy name: multitenancy spec: ingress: - from: - namespaceSelector: matchLabels: kubernetes.io/metadata.name: istio-system podSelector: matchLabels: app: istio-ingressgateway podSelector: matchLabels: release: multitenancy policyTypes: - Ingress ``` > Replace the placeholders with the values that you got in the previous steps. ### Deploy Application into SAP BTP, Kyma runtime Deploy the Node.js application by executing this command under the root directory `multitenancy-kyma-tutorial`: ```Shell / Bash kubectl -n multitenancy-ns apply -f k8s-deployment-backend.yaml ``` ### Check Application Deployment state Launch Kyma dashboard from SAP BTP cockpit, then navigate to the `multitenancy-ns` namespace. Go to `Workloads`, and then select `Deployments`. You will see deployment of **kyma-multitenant-node-multitenancy** displayed, with its `Pods` status shown in green. At this point, your application has been deployed successfully. ![deploy_succeed.png](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/deploy-nodejs-application-kyma/deploy_succeed.png) ### Access Application in Browser **1.** Find the URL address of your application in Kyma dashboard: ![api_rule_host](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/deploy-nodejs-application-kyma/api_rule_host.png) **2.** Access it in the browser, then the application will return the message "Hello World!". ### Project Repository You can find the final Node.js project from repository: [here](https://github.com/SAP-samples/btp-kyma-runtime-multitenancy-tutorial/tree/main/Mission%20-%20Develop%20a%20Node.js%20Application%20in%20the%20SAP%20BTP%20Kyma%20Runtime). ---