fix: resolve cumulative update links from new Microsoft download pages

.github/copilot-instructions.md

@@ -46,7 +46,7 @@ The build step (`npm run build`) also runs `npm run docs`, which regenerates the
 2. Validates OS compatibility using version config from `src/versions.ts`
 3. Optionally installs SQL Native Client (`src/install-native-client.ts`) and ODBC driver (`src/install-odbc.ts`)
 4. Downloads or cache-hits the SQL Server installer (box+exe, standalone exe, or SSEI bootstrapper)
-5. Optionally downloads cumulative updates
+5. Optionally downloads cumulative updates (resolves Microsoft download-page JSON or legacy links, retries transient page-fetch failures, and warns then installs without updates if the download fails)
 6. Runs the installer via `@actions/exec`
 7. Waits for the database to be ready (exponential backoff)
 

README.md

@@ -47,6 +47,12 @@ See [action.yml](./action.yml):
 ```
 <!-- end usage -->
 
+When `install-updates: true` is set for a version with a configured update URL,
+the action downloads the update before starting SQL Server setup. Transient
+download-page failures are tried up to three times. If the update still can't be
+downloaded, the action logs a warning with the reason and installs SQL Server
+without updates. Versions without a configured update URL skip updates.
+
 ### Basic usage
 
 ```yml

src/install.ts

@@ -103,7 +103,14 @@ export default async function install() {
         if (!config.updateUrl) {
             core.info('Skipping update installation - version not supported');
         } else {
-            const updatePath = await core.group(`Fetching cumulative updates for ${version}`, () => findOrDownloadUpdates(config));
+            const updatePath = await core.group(`Fetching cumulative updates for ${version}`, async () => {
+                try {
+                    return await findOrDownloadUpdates(config);
+                } catch (error) {
+                    core.warning(`Unable to download cumulative updates; installing without updates. ${error}`);
+                    return '';
+                }
+            });
             if (updatePath) {
                 installArgs.push('/UPDATEENABLED=1', `/UpdateSource=${dirname(updatePath)}`);
             }

src/utils.ts

@@ -1,5 +1,6 @@
 import { basename, extname, dirname, join as joinPaths } from 'node:path';
 import { readdir } from 'node:fs/promises';
+import { setTimeout as delay } from 'node:timers/promises';
 import * as core from '@actions/core';
 import * as exec from '@actions/exec';
 import * as glob from '@actions/glob';
@@ -226,8 +227,75 @@ export async function downloadExeInstaller(config: VersionConfig): Promise<strin
     return joinPaths(toolPath, 'setup.exe');
 }
 
+function isUpdateDownloadUrl(value: unknown): value is string {
+    return typeof value === 'string' && /^https:\/\/download\.microsoft\.com\/[^\s"'<>?#]+\.exe$/i.test(value);
+}
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+    return typeof value === 'object' && value !== null && !Array.isArray(value);
+}
+
+function extractUpdateDownloadUrl(body: string): string {
+    const links = new Set<string>();
+    for (const [, script] of body.matchAll(/<script\b[^>]*>([\s\S]*?)<\/script\s*>/gi)) {
+        const assignment = script.match(/^\s*window\.__DLCDetails__\s*=\s*(\{[\s\S]*\})\s*;?\s*$/);
+        if (!assignment) continue;
+        let details: unknown;
+        try {
+            details = JSON.parse(assignment[1]);
+        } catch (error) {
+            throw new Error('Invalid cumulative update metadata in Microsoft download page', { cause: error });
+        }
+        if (!isRecord(details) || !isRecord(details.dlcDetailsView)) {
+            throw new Error('Invalid cumulative update metadata in Microsoft download page');
+        }
+        const files = details.dlcDetailsView.downloadFile;
+        if (!Array.isArray(files)) {
+            throw new Error('Invalid cumulative update file list in Microsoft download page');
+        }
+        for (const file of files) {
+            if (isRecord(file) && isUpdateDownloadUrl(file.url)) links.add(file.url);
+        }
+    }
+    if (!links.size) {
+        for (const [, link] of body.matchAll(/<a\b[^>]*?\s+href\s*=\s*["']([^"']+)["'][^>]*>/gi)) {
+            if (isUpdateDownloadUrl(link)) links.add(link);
+        }
+    }
+    if (links.size !== 1) {
+        throw new Error(links.size
+            ? 'Multiple cumulative update installers found in Microsoft download page'
+            : 'No HTTPS download.microsoft.com .exe cumulative update installer found in Microsoft download page');
+    }
+    return links.values().next().value!;
+}
+
+async function fetchUpdatePage(url: string): Promise<string> {
+    const attempts = 3;
+    for (let attempt = 1; ; attempt++) {
+        let retryable = false;
+        try {
+            const res = await fetch(url, { signal: AbortSignal.timeout(30_000) });
+            if (!res.ok) {
+                retryable = res.status === 408 || res.status === 429 || res.status >= 500;
+                throw new Error(`HTTP ${res.status}`);
+            }
+            return await res.text();
+        } catch (error) {
+            retryable ||= error instanceof TypeError || (error instanceof Error && error.name === 'TimeoutError');
+            const reason = error instanceof Error ? error.message : String(error);
+            if (!retryable || attempt === attempts) {
+                throw new Error(`Unable to fetch cumulative update page ${url} after ${attempt} attempt(s): ${reason}`, { cause: error });
+            }
+            core.warning(`Cumulative update page fetch failed (${reason}); retrying (${attempt + 1}/${attempts})`);
+            await delay(1000 * attempt);
+        }
+    }
+}
+
 /**
- * Downloads cumulative updates for supported versions.
+ * Downloads cumulative updates for supported versions. Throws with the failure
+ * reason if a configured update cannot be fetched or resolved.
  *
  * @param {VersionConfig} config
  * @returns {Promise<string>}
@@ -236,28 +304,11 @@ export async function downloadUpdateInstaller(config: VersionConfig): Promise<st
     if (!config.updateUrl) {
         throw new Error('No update url provided');
     }
-    // resolve download url
-    let downloadLink: string | null = null;
-    if (!config.updateUrl.endsWith('.exe')) {
-        const res = await fetch(config.updateUrl);
-        if (res.ok) {
-            const body = await res.text();
-            const [, link] = body.match(/\s+href\s*=\s*["'](https:\/\/download\.microsoft\.com\/.*\.exe)['"]/) ?? [];
-            if (link) {
-                downloadLink = link;
-            } else {
-                core.info('Unable to find download link in body');
-                core.debug(body);
-            }
-        }
-        if (!downloadLink) {
-            core.warning('Unable to download cumulative updates');
-            core.info(`Response code: ${res.status}`);
-            return '';
-        }
-    }
-    core.info(`Downloading cumulative update from ${downloadLink ?? config.updateUrl}`);
-    const updatePath = await downloadTool(downloadLink ?? config.updateUrl);
+    const downloadLink = config.updateUrl.endsWith('.exe')
+        ? config.updateUrl
+        : extractUpdateDownloadUrl(await fetchUpdatePage(config.updateUrl));
+    core.info(`Downloading cumulative update from ${downloadLink}`);
+    const updatePath = await downloadTool(downloadLink);
     if (core.isDebug()) {
         const hash = await generateFileHash(updatePath);
         core.debug(`Got update file with hash SHA256=${hash.toString('base64')}`);

test/install.ts

@@ -173,6 +173,17 @@ describe('install', () => {
         assert.ok(args.includes('/UPDATEENABLED=1'));
         assert.ok(args.includes('/UpdateSource=C:/tool-cache/sql-update'));
     });
+    it('installs without updates and warns if requested updates fail', async () => {
+        utils.gatherInputs.mock.mockImplementation(() => defaultInputs({ installUpdates: true }));
+        utils.downloadUpdateInstaller.mock.mockImplementation(async () => {
+            throw new Error('Unable to fetch cumulative update page: HTTP 403');
+        });
+        await install();
+        const args = exec.exec.mock.calls[0].arguments[1] as string[];
+        assert.ok(!args.includes('/UPDATEENABLED=1'));
+        assert.ok(!args.some((arg) => arg.startsWith('/UpdateSource=')));
+        assert.ok(core.warning.mock.calls.some((call) => /installing without updates\. Error: Unable to fetch cumulative update page: HTTP 403/.test(String(call.arguments[0]))));
+    });
     it('skips cumulative updates if no update url', async () => {
         utils.gatherInputs.mock.mockImplementation(() => defaultInputs({ version: 'minOs', installUpdates: true }));
         await install();