feat: Compute the kubectl download version map at build time

- Allows for bundled kubectl config to be changed without code changes

- Introduce @k8slens/kubectl-versions

  - Compile time fetching of versions

- Update @swc/* packages

Signed-off-by: Sebastian Malton <sebastian@malton.name>

packages/kubectl-versions/build/compute-versions.ts

@@ -0,0 +1,63 @@
+import fetch from "node-fetch";
+import { TypedRegEx } from "typed-regex";
+import { XMLParser } from "fast-xml-parser";
+import semver from "semver";
+import { writeFile } from "fs/promises";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const { SemVer } = semver;
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+
+const expectedResponseForm = TypedRegEx("v(?<version>\\d+\\.\\d+\\.\\d+)");
+
+async function requestGreatestKubectlPatchVersion(majorMinor: string): Promise<string | undefined> {
+  const response = await fetch(`https://dl.k8s.io/release/stable-${majorMinor}.txt`);
+
+  if (response.status !== 200) {
+    try {
+      const parser = new XMLParser();
+      const errorBody = parser.parse(await response.text());
+
+      throw new Error(`failed to get stable version for ${majorMinor}: ${errorBody?.Error?.Message ?? response.statusText}`);
+    } catch {
+      throw new Error(`failed to get stable version for ${majorMinor}: ${response.statusText}`);
+    }
+  }
+
+  const body = await response.text();
+  const match = expectedResponseForm.captures(body);
+
+  if (!match) {
+    throw new Error(`failed to get stable version for ${majorMinor}: unexpected response shape. body="${body}"`);
+  }
+
+  return match.version;
+}
+
+async function requestAllVersions(): Promise<[string, string][]> {
+  const greatestVersion = await requestGreatestKubectlPatchVersion("1");
+
+  if (!greatestVersion) {
+    return [];
+  }
+
+  const greatestSemVer = new SemVer(greatestVersion);
+  const majorMinorRequests = new Array<string>(greatestSemVer.minor + 1)
+    .fill("")
+    .map((value, index) => `1.${index}`)
+    .map(async (majorMinor) => [majorMinor, await requestGreatestKubectlPatchVersion(majorMinor)] as const);
+
+  return (await Promise.all(majorMinorRequests))
+    .filter((entry): entry is [string, string] => !!entry[1]);
+}
+
+async function main() {
+  const versions = await requestAllVersions();
+
+  await writeFile(path.join(__dirname, "versions.json"), JSON.stringify(versions, null, 4));
+}
+
+await main();