Add --github-pr-number to derive ref from PR #

Author: kraenhansen

.evergreen/functions.yml

@@ -669,7 +669,11 @@ functions:
           # Load environment variables
           eval $(.evergreen/print-compass-env.sh)
           # Start the smoke tests on GitHub Actions and wait for successful completion
-          npm run --workspace @mongodb-js/compass-smoke-tests start -- dispatch --ref ${trigger_branch}
+          if [[ "${requester}" == "github_pr" ]]; then
+            npm run --workspace @mongodb-js/compass-smoke-tests start -- dispatch --github-pr-number ${github_pr_number}
+          else
+            npm run --workspace @mongodb-js/compass-smoke-tests start -- dispatch --ref ${branch_name}
+          fi
 
   test-web-sandbox:
     - command: shell.exec

packages/compass-smoke-tests/src/cli.ts

@@ -13,7 +13,7 @@ import { testTimeToFirstQuery } from './tests/time-to-first-query';
 import { testAutoUpdateFrom } from './tests/auto-update-from';
 import { testAutoUpdateTo } from './tests/auto-update-to';
 import { deleteSandboxesDirectory } from './directories';
-import { dispatchAndWait } from './dispatch';
+import { dispatchAndWait, getRefFromGithubPr } from './dispatch';
 
 const debug = createDebug('compass:smoketests');
 
@@ -135,6 +135,10 @@ yargs(hideBin(process.argv))
     'Dispatch smoke tests on GitHub and watch to completion',
     (argv) =>
       argv
+        .option('github-pr-number', {
+          type: 'number',
+          description: 'GitHub PR number used to determine ref',
+        })
         .option('ref', {
           type: 'string',
           description: 'Git reference to dispatch the workflow from',
@@ -145,7 +149,7 @@ yargs(hideBin(process.argv))
           description: 'Compass version to run tests for',
           default: process.env.DEV_VERSION_IDENTIFIER,
         }),
-    async ({ version, bucketName, bucketKeyPrefix, ref }) => {
+    async ({ version, bucketName, bucketKeyPrefix, ref, githubPrNumber }) => {
       const { GITHUB_TOKEN } = process.env;
       assert(
         typeof GITHUB_TOKEN === 'string',
@@ -161,7 +165,13 @@ yargs(hideBin(process.argv))
       );
       await dispatchAndWait({
         githubToken: GITHUB_TOKEN,
-        ref,
+        ref:
+          typeof githubPrNumber === 'number'
+            ? await getRefFromGithubPr({
+                githubToken: GITHUB_TOKEN,
+                githubPrNumber,
+              })
+            : ref,
         version,
         bucketName,
         bucketKeyPrefix,

packages/compass-smoke-tests/src/dispatch.ts

@@ -47,6 +47,29 @@ async function getWorkflowRunRetrying(
   );
 }
 
+type RefFromGithubPrOptions = {
+  githubToken: string;
+  githubPrNumber: number;
+};
+
+export async function getRefFromGithubPr({
+  githubToken,
+  githubPrNumber,
+}: RefFromGithubPrOptions) {
+  const octokit = github.getOctokit(githubToken);
+  const {
+    data: {
+      head: { ref },
+    },
+  } = await octokit.rest.pulls.get({
+    owner: GITHUB_OWNER,
+    repo: GITHUB_REPO,
+    pull_number: githubPrNumber,
+  });
+  console.log(`Got ref "${ref}" from PR #${githubPrNumber}`);
+  return ref;
+}
+
 type DispatchOptions = {
   githubToken: string;
   ref: string;