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Modify a YAML Document

Modifying YAML documents is a simple but powerful feature of Anemos. It allows you to change the content of a document anywhere in the code.

The following example shows various ways to modify a YAML document. See the API reference for more ways to modify a document.

index.ts
import * as anemos from "@ohayocorp/anemos";

const builder = new anemos.Builder("1.31", anemos.KubernetesDistribution.Minikube, anemos.EnvironmentType.Development);

const document = new anemos.Document("modified.yaml");

// Set simple values.
const root = document.getRoot();

root.set("apiVersion", "apps/v1");
root.set("kind", "Deployment");

// Set objects as values.
root.set("metadata", {
    name: "modified",
    namespace: "default",
});

// Create chain of objects. Here "spec", "template" and "spec" are all created and the last mapping
// is returned.
const templateSpec = root.ensureMapping(["spec", "template", "spec"]);

// Set an array as YAML sequence.
templateSpec.set("containers", [
    {
        name: "modified",
        image: "nginx:latest",
    },
]);

// Anemos has some convenience methods for Kubernetes objects. For example, `getContainer` returns the
// container of a workload with given name.
const container = document.getContainer("modified");
container?.set("imagePullPolicy", "Always");

builder.addDocument(document);
builder.build();

This example creates the following YAML document:

modified.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: modified
  namespace: default
spec:
  template:
    spec:
      containers:
        - name: modified
          image: nginx:latest
          imagePullPolicy: Always