Initialise API client

Author: mbg

package-lock.json

@@ -6,6 +6,10 @@
   },
   "devDependencies": {
     "@actions/core": "*",
+    "@actions/github": "*",
+    "@octokit/core": "*",
+    "@octokit/plugin-paginate-rest": "*",
+    "@octokit/plugin-rest-endpoint-methods": "*",
     "@types/node": "^20.19.9",
     "tsx": "^4.21.0",
     "typescript": "^5.9.3"

pr-checks/package.json

@@ -4,8 +4,22 @@
 
 import { parseArgs } from "node:util";
 
+import * as githubUtils from "@actions/github/lib/utils";
+import { type Octokit } from "@octokit/core";
+import { type PaginateInterface } from "@octokit/plugin-paginate-rest";
+import { type Api } from "@octokit/plugin-rest-endpoint-methods";
+
 import { OLDEST_SUPPORTED_MAJOR_VERSION } from "./config";
 
+/** The type of the Octokit client. */
+type ApiClient = Octokit & Api & { paginate: PaginateInterface };
+
+/** Constructs an `ApiClient` using `token` for authentication. */
+function getApiClient(token: string): ApiClient {
+  const opts = githubUtils.getOctokitOptions(token);
+  return new githubUtils.GitHub(opts);
+}
+
 async function main(): Promise<void> {
   const { values: options } = parseArgs({
     options: {
@@ -37,6 +51,9 @@ async function main(): Promise<void> {
     `Oldest supported major version is: ${OLDEST_SUPPORTED_MAJOR_VERSION}`,
   );
 
+  // Initialise the API client.
+  const client = getApiClient(options.token);
+
   process.exit(0);
 }