Deploying with Helm

This guide walks you through deploying the Sendent for Outlook (cross-platform) on a Kubernetes cluster using Helm.

Prerequisites

• A running Kubernetes cluster (v1.19 or later)

• Helm installed on your local machine

• kubectl configured to access your cluster

• A running Nextcloud instance

• A domain name pointing to your cluster (e.g., outlook.example.com)

Step 1: Get the Helm Chart

Sendent maintains the Helm charts in our public GitHub repository. To get started, clone the repository from the following location: https://github.com/Sendent-B-V/sendent-container-helm-charts/tree/main/outlook-addin and follow the README instructions.

Step 2: Create your values file

Create a file called my-values.yaml with your configuration:

config:
  BASE_URL: https://outlook.example.com                    # your outlook domain
  DEFAULT_NEXTCLOUD_URL: https://nextcloud.example.com     # your nextcloud domain
  MS_AUTH_TYPE: naa_silent                                 # one of naa_silent, legacy_exchange
  MS_APP_ID: your-azure-app-id
  MS_TENANT_ID: your-azure-tenant-id

We recommend following this article to set up authentication.

Full configuration reference

Deployment parameters

The add-in is stateless, so it can be scaled horizontally by increasing replicaCount:

replicaCount: 3

For production deployments, it is recommended to set resource requests and limits:

resources:
    requests:
      cpu: 100m
      memory: 128Mi
    limits:
      cpu: 500m
      memory: 256Mi

Step 3: Install the chart

To install the Helm chart, run

helm install sendent-outlook ./outlook-addin -f my-values.yaml

Verify the deployment is running:

kubectl get pods -l app.kubernetes.io/name=outlook-addin

You should see your pod(s) in Running status.

4: Expose the add-in

The chart creates a ClusterIP service on port 4300 by default. You need to expose this externally so Outlook can reach it. There are a few options depending on your cluster setup.

Option A: Ingress (recommended)

The chart can create an Ingress resource to expose the add-in externally. This requires an ingress controller (e.g. ingress-nginx) and cert-manager (for automatic TLS certificates).

Install an Ingress controller (if not already present):

helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
 
helm install ingress-nginx ingress-nginx/ingress-nginx \
  --namespace ingress-nginx --create-namespace

Install cert-manager (if not already present):

helm repo add jetstack https://charts.jetstack.io
 
helm install cert-manager jetstack/cert-manager \
  --namespace cert-manager --create-namespace \
  --set crds.enabled=true

Create a ClusterIssuer for Let’s Encrypt

Make sure to change the example email (Let’s Encrypt uses it for expiry notices).

# cluster-issue.yaml
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
  name: letsencrypt-prod
spec:
  acme:
    server: https://acme-v02.api.letsencrypt.org/directory
    email: your-email@example.com
    privateKeySecretRef:
      name: letsencrypt-prod
    solvers:
      - http01:
          ingress:
            class: nginx

kubectl apply -f cluster-issuer.yaml

Configure your DNS

Retrieve the controller’s external IP:

kubectl get svc -n ingress-nginx

For example:

NAME                                 TYPE           CLUSTER-IP     EXTERNAL-IP     PORT(S)
ingress-nginx-controller             LoadBalancer   10.10.10.10   140.10.10.10   80:32554/TCP,443:32677/TCP

Point your domain's A record at the ingress controller's external IP.

Update your values file with the ingress configuration

Finally, add the following to your values file:

ingress:
    enabled: true
    className: nginx     # adjust to match your ingress controller
    annotations:
      cert-manager.io/cluster-issuer: letsencrypt-prod
    hosts:
      - host: outlook.example.com
        paths:
          - path: /
            pathType: Prefix
    tls:
      - secretName: outlook-addin-tls
        hosts:
          - outlook.example.com

Adjust className, annotations, and tls to match your cluster's ingress setup.

Option B: Reverse proxy

If you prefer to manage routing outside of Kubernetes, keep the default ClusterIP service and point your existing reverse proxy (e.g., Nginx, Caddy) at the service. You can use kubectl port-forward to expose the service internally to your reverse proxy, and then configure it to serve https://outlook.example.com.

kubectl port-forward svc/sendent-outlook-outlook-addin 4300:4300

Step 5: Verify the deployment

Open https://outlook.example/manifest.xml in your browser. You should see the manifest XML. If this loads correctly, the deployment works and you can proceed to install the add-in in Outlook using this manifest URL.

Uninstalling

To uninstall the Helm chart, run

helm uninstall sendent-outlook

Troubleshooting

Check pod status:

kubectl get pods -l app.kubernetes.io/name=outlook-addin

View pod events and details:

kubectl describe pod -l app.kubernetes.io/name=outlook-addin

View application logs:

kubectl logs -l app.kubernetes.io/name=outlook-addin

If your pods are in CrashLoopBackOff, check the logs for configuration errors. The most common issues are missing BASE_URL or authentication configuration parameters.