diff --git a/.changeset/four-tips-accept.md b/.changeset/four-tips-accept.md
new file mode 100644
index 0000000000..bfab504736
--- /dev/null
+++ b/.changeset/four-tips-accept.md
@@ -0,0 +1,23 @@
+---
+'astro': patch
+---
+
+Allow passing a cryptography key via ASTRO_KEY
+
+For Server islands Astro creates a cryptography key in order to hash props for the islands, preventing accidental leakage of secrets.
+
+If you deploy to an environment with rolling updates then there could be multiple instances of your app with different keys, causing potential key mismatches.
+
+To fix this you can now pass the `ASTRO_KEY` environment variable to your build in order to reuse the same key.
+
+To generate a key use:
+
+```
+astro create-key
+```
+
+This will print out an environment variable to set like:
+
+```
+ASTRO_KEY=PIAuyPNn2aKU/bviapEuc/nVzdzZPizKNo3OqF/5PmQ=
+```
diff --git a/packages/astro/e2e/fixtures/server-islands-key/astro.config.mjs b/packages/astro/e2e/fixtures/server-islands-key/astro.config.mjs
new file mode 100644
index 0000000000..db1a7b4524
--- /dev/null
+++ b/packages/astro/e2e/fixtures/server-islands-key/astro.config.mjs
@@ -0,0 +1,12 @@
+import { defineConfig } from 'astro/config';
+import node from '@astrojs/node';
+
+// https://astro.build/config
+export default defineConfig({
+ output: 'server',
+ adapter: node({ mode: 'standalone' }),
+ integrations: [],
+ experimental: {
+ serverIslands: true,
+ }
+});
diff --git a/packages/astro/e2e/fixtures/server-islands-key/package.json b/packages/astro/e2e/fixtures/server-islands-key/package.json
new file mode 100644
index 0000000000..b03c575c7e
--- /dev/null
+++ b/packages/astro/e2e/fixtures/server-islands-key/package.json
@@ -0,0 +1,12 @@
+{
+ "name": "@e2e/server-islands-key",
+ "version": "0.0.0",
+ "private": true,
+ "scripts": {
+ "dev": "astro dev"
+ },
+ "dependencies": {
+ "astro": "workspace:*",
+ "@astrojs/node": "^8.3.3"
+ }
+}
diff --git a/packages/astro/e2e/fixtures/server-islands-key/src/components/Island.astro b/packages/astro/e2e/fixtures/server-islands-key/src/components/Island.astro
new file mode 100644
index 0000000000..5eab0dc4df
--- /dev/null
+++ b/packages/astro/e2e/fixtures/server-islands-key/src/components/Island.astro
@@ -0,0 +1,6 @@
+---
+const { secret } = Astro.props;
+---
+I am an island
+
+{secret}
diff --git a/packages/astro/e2e/fixtures/server-islands-key/src/pages/index.astro b/packages/astro/e2e/fixtures/server-islands-key/src/pages/index.astro
new file mode 100644
index 0000000000..a19aa8a275
--- /dev/null
+++ b/packages/astro/e2e/fixtures/server-islands-key/src/pages/index.astro
@@ -0,0 +1,14 @@
+---
+import Island from '../components/Island.astro';
+---
+
+
+
+
+
+
+
+ children
+
+
+
diff --git a/packages/astro/e2e/server-islands-key.test.js b/packages/astro/e2e/server-islands-key.test.js
new file mode 100644
index 0000000000..2120d1368f
--- /dev/null
+++ b/packages/astro/e2e/server-islands-key.test.js
@@ -0,0 +1,33 @@
+import { expect } from '@playwright/test';
+import { testFactory } from './test-utils.js';
+
+const test = testFactory(import.meta.url, { root: './fixtures/server-islands-key/' });
+
+test.describe('Server islands - Key reuse', () => {
+ test.describe('Production', () => {
+ let previewServer;
+
+ test.beforeAll(async ({ astro }) => {
+ // Playwright's Node version doesn't have these functions, so stub them.
+ process.stdout.clearLine = () => {};
+ process.stdout.cursorTo = () => {};
+ process.env.ASTRO_KEY = 'eKBaVEuI7YjfanEXHuJe/pwZKKt3LkAHeMxvTU7aR0M=';
+ await astro.build();
+ previewServer = await astro.preview();
+ });
+
+ test.afterAll(async () => {
+ await previewServer.stop();
+ delete process.env.ASTRO_KEY;
+ });
+
+ test('Components render properly', async ({ page, astro }) => {
+ await page.goto(astro.resolveUrl('/'));
+
+ let el = page.locator('#island');
+
+ await expect(el, 'element rendered').toBeVisible();
+ await expect(el, 'should have content').toHaveText('I am an island');
+ });
+ });
+});
diff --git a/packages/astro/e2e/test-utils.js b/packages/astro/e2e/test-utils.js
index 933186a718..7ae2e552a5 100644
--- a/packages/astro/e2e/test-utils.js
+++ b/packages/astro/e2e/test-utils.js
@@ -14,6 +14,10 @@ const testFileToPort = new Map();
for (let i = 0; i < testFiles.length; i++) {
const file = testFiles[i];
if (file.endsWith('.test.js')) {
+ // Port 4045 is an unsafe port in Chrome, so skip it.
+ if((4000 + i) === 4045) {
+ i++;
+ }
testFileToPort.set(file, 4000 + i);
}
}
diff --git a/packages/astro/src/cli/create-key/index.ts b/packages/astro/src/cli/create-key/index.ts
new file mode 100644
index 0000000000..55091d5059
--- /dev/null
+++ b/packages/astro/src/cli/create-key/index.ts
@@ -0,0 +1,31 @@
+import { type Flags, flagsToAstroInlineConfig } from '../flags.js';
+import { createNodeLogger } from '../../core/config/logging.js';
+import { createKey as createCryptoKey,encodeKey } from '../../core/encryption.js';
+
+interface CreateKeyOptions {
+ flags: Flags;
+}
+
+export async function createKey({ flags }: CreateKeyOptions): Promise<0 | 1> {
+ try {
+ const inlineConfig = flagsToAstroInlineConfig(flags);
+ const logger = createNodeLogger(inlineConfig);
+
+ const keyPromise = createCryptoKey();
+ const key = await keyPromise;
+ const encoded = await encodeKey(key);
+
+ logger.info('crypto', `Generated a key to encrypt props passed to Server islands. To reuse the same key across builds, set this value as ASTRO_KEY in an environment variable on your build server.
+
+ASTRO_KEY=${encoded}`);
+ } catch(err: unknown) {
+ if(err != null) {
+ // eslint-disable-next-line no-console
+ console.error(err.toString());
+ }
+ return 1;
+ }
+
+
+ return 0;
+}
diff --git a/packages/astro/src/cli/index.ts b/packages/astro/src/cli/index.ts
index c767569fde..23486f938a 100644
--- a/packages/astro/src/cli/index.ts
+++ b/packages/astro/src/cli/index.ts
@@ -7,6 +7,7 @@ type CLICommand =
| 'help'
| 'version'
| 'add'
+ | 'create-key'
| 'docs'
| 'dev'
| 'build'
@@ -30,6 +31,7 @@ async function printAstroHelp() {
['add', 'Add an integration.'],
['build', 'Build your project and write it to disk.'],
['check', 'Check your project for errors.'],
+ ['create-key', 'Create a cryptography key'],
['db', 'Manage your Astro database.'],
['dev', 'Start the development server.'],
['docs', 'Open documentation in your web browser.'],
@@ -78,6 +80,7 @@ function resolveCommand(flags: yargs.Arguments): CLICommand {
'build',
'preview',
'check',
+ 'create-key',
'docs',
'db',
'info',
@@ -111,6 +114,11 @@ async function runCommand(cmd: string, flags: yargs.Arguments) {
await printInfo({ flags });
return;
}
+ case 'create-key': {
+ const { createKey } = await import('./create-key/index.js');
+ const exitCode = await createKey({ flags });
+ return process.exit(exitCode);
+ }
case 'docs': {
const { docs } = await import('./docs/index.js');
await docs({ flags });
diff --git a/packages/astro/src/core/build/index.ts b/packages/astro/src/core/build/index.ts
index 70d2401284..4253b8802f 100644
--- a/packages/astro/src/core/build/index.ts
+++ b/packages/astro/src/core/build/index.ts
@@ -23,7 +23,7 @@ import { resolveConfig } from '../config/config.js';
import { createNodeLogger } from '../config/logging.js';
import { createSettings } from '../config/settings.js';
import { createVite } from '../create-vite.js';
-import { createKey } from '../encryption.js';
+import { createKey, getEnvironmentKey, hasEnvironmentKey } from '../encryption.js';
import type { Logger } from '../logger/core.js';
import { levels, timerMessage } from '../logger/core.js';
import { apply as applyPolyfill } from '../polyfill.js';
@@ -188,6 +188,9 @@ class AstroBuilder {
green(`✓ Completed in ${getTimeStat(this.timer.init, performance.now())}.`),
);
+ const hasKey = hasEnvironmentKey();
+ const keyPromise = hasKey ? getEnvironmentKey() : createKey();
+
const opts: StaticBuildOptions = {
allPages,
settings: this.settings,
@@ -198,7 +201,7 @@ class AstroBuilder {
pageNames,
teardownCompiler: this.teardownCompiler,
viteConfig,
- key: createKey(),
+ key: keyPromise,
};
const { internals, ssrOutputChunkNames, contentFileNames } = await viteBuild(opts);
diff --git a/packages/astro/src/core/encryption.ts b/packages/astro/src/core/encryption.ts
index ccfc9bdd27..7cfba99d94 100644
--- a/packages/astro/src/core/encryption.ts
+++ b/packages/astro/src/core/encryption.ts
@@ -20,6 +20,35 @@ export async function createKey() {
return key;
}
+// The environment variable name that can be used to provide the encrypted key.
+const ENVIRONMENT_KEY_NAME = 'ASTRO_KEY' as const;
+
+/**
+ * Get the encoded value of the ASTRO_KEY env var.
+ */
+export function getEncodedEnvironmentKey(): string {
+ return process.env[ENVIRONMENT_KEY_NAME] || '';
+}
+
+/**
+ * See if the environment variable key ASTRO_KEY is set.
+ */
+export function hasEnvironmentKey(): boolean {
+ return getEncodedEnvironmentKey() !== '';
+}
+
+/**
+ * Get the environment variable key and decode it into a CryptoKey.
+ */
+export async function getEnvironmentKey(): Promise {
+ // This should never happen, because we always check `hasEnvironmentKey` before this is called.
+ if(!hasEnvironmentKey()) {
+ throw new Error(`There is no environment key defined. If you see this error there is a bug in Astro.`)
+ }
+ const encodedKey = getEncodedEnvironmentKey();
+ return decodeKey(encodedKey);
+}
+
/**
* Takes a key that has been serialized to an array of bytes and returns a CryptoKey
*/
diff --git a/packages/astro/src/core/logger/core.ts b/packages/astro/src/core/logger/core.ts
index c06866df5c..51ebd9325b 100644
--- a/packages/astro/src/core/logger/core.ts
+++ b/packages/astro/src/core/logger/core.ts
@@ -18,6 +18,7 @@ export type LoggerLabel =
| 'check'
| 'config'
| 'content'
+ | 'crypto'
| 'deprecated'
| 'markdown'
| 'router'
diff --git a/packages/astro/test/fixtures/server-islands/ssr/astro.config.mjs b/packages/astro/test/fixtures/server-islands/ssr/astro.config.mjs
index 8eb474b048..79ce4c497a 100644
--- a/packages/astro/test/fixtures/server-islands/ssr/astro.config.mjs
+++ b/packages/astro/test/fixtures/server-islands/ssr/astro.config.mjs
@@ -1,7 +1,9 @@
import svelte from '@astrojs/svelte';
import { defineConfig } from 'astro/config';
+import testAdapter from '../../../test-adapter.js';
export default defineConfig({
+ adapter: testAdapter(),
output: 'server',
integrations: [
svelte()
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 34b6143194..29ef628484 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -1615,6 +1615,15 @@ importers:
specifier: ^18.3.1
version: 18.3.1(react@18.3.1)
+ packages/astro/e2e/fixtures/server-islands-key:
+ dependencies:
+ '@astrojs/node':
+ specifier: ^8.3.3
+ version: 8.3.3(astro@packages+astro)
+ astro:
+ specifier: workspace:*
+ version: link:../../..
+
packages/astro/e2e/fixtures/solid-circular:
dependencies:
'@astrojs/solid-js':