Deploy the fastapi helm chart on Kubernetes

Question

Pulumi · Accepted Answer

To deploy the FastAPI Helm chart on Kubernetes using Pulumi, you will need to write a program that imports the required Pulumi packages and defines a Helm chart resource.

The `@pulumi/kubernetes` package allows us to interact with Kubernetes resources, including deploying Helm charts. A Helm chart is a package that contains all the necessary resource definitions to deploy an application or service in Kubernetes. The `Chart` resource from Pulumi's Kubernetes provider will help you install the FastAPI helm chart onto your Kubernetes cluster.

Below is a TypeScript program that uses Pulumi to deploy the FastAPI Helm chart. This example assumes you have a Kubernetes cluster already running and that `kubectl` is configured to connect to it. Pulumi will use this existing context to communicate with your cluster.

First, you'll need to install the necessary Node.js dependencies with npm:

```sh
npm install @pulumi/pulumi @pulumi/kubernetes
```

Here's the program that deploys the FastAPI Helm chart:

```typescript
import * as k8s from '@pulumi/kubernetes';

// Define the FastAPI helm chart from a repository
const fastapiChart = new k8s.helm.v3.Chart("fastapi", {
  repo: "helm-repo-name", // Replace with the actual repo name containing the FastAPI Helm chart
  chart: "fastapi-chart-name", // Replace with the actual chart name
  version: "chart-version", // Replace with the specific chart version you want to deploy, if any
  namespace: "fastapi-namespace", // Replace with the namespace where you want to deploy your FastAPI
  // Define values for the Helm chart
  values: {
    // These values will be specific to the FastAPI Helm chart and what it supports.
    // Typically these would include image names, replica counts, and any other necessary configurations.
    // You would replace the following with actual configuration based on the FastAPI chart requirements:
    image: {
      repository: "tiangolo/uvicorn-gunicorn-fastapi", // This is just a placeholder
      tag: "latest", // Using latest for simplicity, specify a tag for more stability
    },
    service: {
      type: "LoadBalancer", // For example, if you want to expose FastAPI with a LoadBalancer service
    },
  },
});

// Export the public Service endpoint to access your FastAPI application
export const fastapiEndpoint = fastapiChart.getResourceProperty("v1/Service", "fastapi-service-name", "status").apply(status => status.loadBalancer.ingress[0].hostname);
```

In this program:

- We import the `@pulumi/kubernetes` package, which provides us with the necessary functions to interact with Kubernetes resources through Pulumi.
- We define the FastAPI helm chart deployment using `new k8s.helm.v3.Chart`, specifying the repository and chart details along with any values we wish to customize.
- We set the `image` and `service` configuration based on assumed defaults - these will need to be adjusted according to the actual FastAPI Helm chart's requirements.
- We export an endpoint, which you can use to access your FastAPI application once it's deployed. Note that this may vary based on the service type you choose and your cloud provider.

Replace the placeholder values with the actual details for the Helm chart repository, chart name, version, and any other configurations related to the FastAPI chart that you are deploying.

After you've written your program, you can run it using the Pulumi CLI. First, you'll need to create a new Pulumi project and then run the following commands:

1. `pulumi new typescript` — to scaffold a new Pulumi TypeScript project.
2. Replace the contents of `index.ts` with the code provided above.
3. Run `pulumi up` to preview and deploy the resources.

Before running the `pulumi up` command, ensure your `kubectl` context is pointing to the intended Kubernetes cluster and that you have the appropriate permissions in the cluster to create resources.