From 5406c2d62938f2cf6aa3274de57fadf9f7460366 Mon Sep 17 00:00:00 2001
From: Robert Tyree <rtyree@newrelic.com>
Date: Mon, 20 Dec 2021 11:43:00 -0800
Subject: [PATCH] feat: Add github helpers util

---
 utils/github-api-helpers.js | 44 +++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)
 create mode 100644 utils/github-api-helpers.js

diff --git a/utils/github-api-helpers.js b/utils/github-api-helpers.js
new file mode 100644
index 0000000000..0725693b03
--- /dev/null
+++ b/utils/github-api-helpers.js
@@ -0,0 +1,44 @@
+'use strict';
+
+const fetch = require('node-fetch');
+const parseLinkHeader = require('parse-link-header');
+
+/**
+ * Pulls the next page off of a `Link` header
+ * @param {String} linkHeader the `Link` header value
+ * @returns {String|Null} the next page of results
+ */
+const getNextLink = (linkHeader) => {
+  const parsedLinkHeader = parseLinkHeader(linkHeader);
+  if (parsedLinkHeader && parsedLinkHeader.next) {
+    return parsedLinkHeader.next.url || null;
+  }
+  return null;
+};
+
+/**
+ * Fetches paginated results from the Github API
+ * @param {String} url the API to query
+ * @param {String} token a token for the API
+ * @returns {Promise<Object[]>} all pages of results
+ */
+const fetchPaginatedGHResults = async (url, token) => {
+  let files = [];
+  let nextPageLink = url;
+  while (nextPageLink) {
+    const resp = await fetch(nextPageLink, {
+      headers: { authorization: `token ${token}` },
+    });
+    if (!resp.ok) {
+      throw new Error(
+        `Github API returned status ${resp.code} - ${resp.message}`
+      );
+    }
+    const page = await resp.json();
+    nextPageLink = getNextLink(resp.headers.get('Link'));
+    files = [...files, ...page];
+  }
+  return files;
+};
+
+module.exports = { fetchPaginatedGHResults, getNextLink };
\ No newline at end of file