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* add back getting started page * decollapse getting started guide * update style * remove quickstart files scss file * lint * assets * update links * update links * update links * update links * update link
145 lines
5.7 KiB
Markdown
145 lines
5.7 KiB
Markdown
---
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title: "Generate Kubernetes YAML with Familiar Programming Languages"
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date: 2020-03-03
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draft: false
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meta_desc: Stop writing Kubernetes YAML by hand, and start using the power of familiar programming languages! Pulumi now supports rendering YAML for Kubernetes resources.
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meta_image: yamlRuler.png
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authors:
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- levi-blackstone
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tags:
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- kubernetes
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- yaml
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---
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Stop writing Kubernetes YAML by hand, and start using the power of familiar programming languages! Pulumi can
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generate Kubernetes manifests that easily integrate into existing CI/CD workflows.
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<!--more-->
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While Pulumi has [excellent support](https://www.pulumi.com/docs/clouds/kubernetes/get-started/) for deploying and updating
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Kubernetes resources on a cluster, many users have asked for the option to render YAML that they can integrate into
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existing workflows. The [v1.5.4](https://github.com/pulumi/pulumi-kubernetes/releases/tag/v1.5.4) release of
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`pulumi-kubernetes` adds the [renderYamlToDirectory](https://www.pulumi.com/docs/reference/pkg/nodejs/pulumi/kubernetes/#ProviderArgs-renderYamlToDirectory)
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option, which enables this feature. This option is available in every Pulumi-supported language, including
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TypeScript/JavaScript, Python, and .NET ([Go support is coming soon!](https://github.com/pulumi/pulumi-kubernetes/issues/70)).
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Aside from easily templating configuration across resources, using a familiar programming language allows you to write and
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consume libraries, and easily mix in infrastructure configuration (e.g., managed database endpoints, object storage,
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etc.), all in the same program.
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## Rendering YAML from TypeScript
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First, choose a directory for the rendered manifests, and specify that path on a `Provider`.
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```typescript
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import * as k8s from "@pulumi/kubernetes";
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import * as kx from "@pulumi/kubernetesx";
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// Instantiate a Kubernetes Provider and specify the render directory.
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const provider = new k8s.Provider("render-yaml", {
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renderYamlToDirectory: "rendered",
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});
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```
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Next, use that `Provider` for any Kubernetes resources you want to render as YAML.
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```typescript
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// Create a Kubernetes PersistentVolumeClaim.
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const pvc = new kx.PersistentVolumeClaim("data", {
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spec: {
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accessModes: [ "ReadWriteOnce" ],
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resources: { requests: { storage: "1Gi" } },
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}
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}, { provider });
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// Create a Kubernetes ConfigMap.
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const cm = new kx.ConfigMap("cm", {
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data: { "config": "very important data" },
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}, { provider });
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// Create a Kubernetes Secret.
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const secret = new kx.Secret("secret", {
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stringData: {
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"password": new random.RandomPassword("pw", {
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length: 12}).result,
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}
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}, { provider });
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// Define a Pod.
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const pb = new kx.PodBuilder({
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containers: [{
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env: {
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CONFIG: cm.asEnvValue("config"),
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PASSWORD: secret.asEnvValue("password"),
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},
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image: "nginx",
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ports: {http: 8080},
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volumeMounts: [ pvc.mount("/data") ],
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}]
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});
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// Create a Kubernetes Deployment.
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const deployment = new kx.Deployment("nginx", {
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spec: pb.asDeploymentSpec( { replicas: 3 } ),
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}, { provider });
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// Create a Kubernetes Service.
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const service = deployment.createService({
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type: kx.types.ServiceType.LoadBalancer,
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});
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```
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Now, run `pulumi update`, and Pulumi renders these resources to YAML. The update process resolves [Outputs](/docs/concepts/inputs-outputs/)
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as usual, so that the manifests can include other infrastructure configuration specified in your program. The rendered
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manifests are kept in sync with changes to the program on each update.
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Here's what the resulting directory looks like:
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Note that `CustomResourceDefinition` resources need to be applied first, so they are rendered in a separate
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subdirectory. (This example doesn't include any CRDs, so the directory is empty). You could deploy the rendered
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manifests with `kubectl` like this:
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```shell script
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kubectl apply -f "${RENDER_DIRECTORY}/0-crd"
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kubectl apply -f "${RENDER_DIRECTORY}/1-manifest"
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```
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Voilà! From 33 (44 with whitespace and comments) lines of TypeScript code to 102 lines of YAML!
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Here's the rendered `Deployment` resource.
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{{< gist lblackstone 686935edf7fdcd23d916f34d35bba64a "deployment-nginx-nyn4tlkx.yaml" >}}
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See [this gist](https://gist.github.com/lblackstone/686935edf7fdcd23d916f34d35bba64a) for the complete rendered output.
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## Caveats
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There are two important caveats to note about YAML rendering support:
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1. The YAML-rendered resources are **not created** on a Kubernetes cluster, so information that is computed server-side
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will not be available in your program. For example, a `Service` will not have IP assignments, so attempting to export
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these values will not work as usual (i.e., the value will be `undefined`).
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1. **Any Secret values will appear in plaintext in the rendered manifests.** This includes any values marked as
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secret in Pulumi. A warning will be printed for any secret values being rendered to YAML, but it is your responsibility
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to protect the rendered files.
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## Learn More
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If you'd like to learn about Pulumi and how to manage your
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infrastructure and Kubernetes through code, [get started today](/docs/get-started/). Pulumi is open
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source and free to use.
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For further examples on how to use Pulumi to create Kubernetes
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clusters, or deploy workloads to a cluster, check out the rest of the
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[Kubernetes tutorials](/registry/packages/kubernetes/how-to-guides/).
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As always, you can check out our code on
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[GitHub](https://github.com/pulumi), follow us on
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[Twitter](https://twitter.com/pulumicorp), subscribe to our [YouTube
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channel](https://www.youtube.com/channel/UC2Dhyn4Ev52YSbcpfnfP0Mw), or
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join our [Community Slack](https://slack.pulumi.com/) channel if you have
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any questions, need support, or just want to say hello.
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