Update documentation

README.md

@@ -509,19 +509,7 @@ Configuration passed to `firebase-admin`'s [`initializeApp`](https://firebase.go
 
 The `firebaseAdminInitConfig.credential.privateKey` cannot be defined on the client side and should live in a secret environment variable.
 
-> Note: if using environment variables in Vercel, add the private key _with double quotes_ via the CLI:
->
-> `vercel secrets add firebase-private-key '"my-key-here"'`
->
-> Then, use `JSON.parse` in the `firebaseAdminInitConfig.credential.privateKey` property:
->
-> ```
->   privateKey: process.env.FIREBASE_PRIVATE_KEY
->     ? JSON.parse(process.env.FIREBASE_PRIVATE_KEY)
->     : undefined
-> ```
->
-> See [this Vercel issue](https://github.com/vercel/vercel/issues/749#issuecomment-707515089) for more information.
+> ℹ️ Using Vercel? See [adding a private key to Vercel](#adding-a-private-key-to-Vercel) for guidance.
 
 #### useFirebaseAdminDefaultCredential
 
@@ -651,11 +639,45 @@ A method that calls Firebase's [`signOut`](https://firebase.google.com/docs/refe
 
 ## Examples
 
+- [Adding a private key to Vercel](#adding-a-private-key-to-Vercel)
 - [Using the Firebase Apps](#using-the-firebase-apps)
 - [TypeScript](#typescript)
 - [Dynamic Redirects](#dynamic-redirects)
 - [Testing and Mocking with Jest](#testing-and-mocking-with-jest)
 
+### Adding a private key to Vercel
+
+There are various ways to add your Firebase private key as an environment variable to Vercel.
+
+__Vercel console__
+
+In the [Vercel console](https://vercel.com/docs/concepts/projects/environment-variables), add the private key in double quotes (screenshot [here](https://github.com/gladly-team/next-firebase-auth/issues/212)).
+
+Then, use the private key in your `next-firebase-auth` config, in the `firebaseAdminInitConfig.credential.privateKey` property:
+
+
+```javascript
+privateKey: process.env.FIREBASE_PRIVATE_KEY
+```
+
+__Vercel CLI__
+
+Via the Vercel CLI, add the private key _with double quotes_:
+
+`vercel secrets add firebase-private-key '"my-key-here"'`
+
+Then, use `JSON.parse` in the `firebaseAdminInitConfig.credential.privateKey` property:
+
+```javascript
+privateKey: process.env.FIREBASE_PRIVATE_KEY
+  ? JSON.parse(process.env.FIREBASE_PRIVATE_KEY)
+  : undefined
+```
+
+__Alternative formatting__
+
+Others have taken different approaches to deal with escaped newline characters in the private key; for example, by [using string replacement](https://stackoverflow.com/a/50376092). This discussion includes other approaches: [discussion #95](https://github.com/gladly-team/next-firebase-auth/discussions/95)
+
 ### Using the Firebase Apps
 
 You may want to access the Firebase admin module or Firebase JS SDK.
@@ -1019,6 +1041,10 @@ You can try setting up your credentials in [the example app](https://github.com/
 
 In local development, try clearing data/cookies for `localhost` in case you previously signed in with another Firebase account and still have auth cookies signed by another private key.
 
+#### I get the error, "Failed to parse private key: Error: Invalid PEM formatted message."
+
+See [adding a private key to Vercel](#adding-a-private-key-to-Vercel) and [this discussion](https://github.com/gladly-team/next-firebase-auth/discussions/95) on private key formatting.
+
 ## Limitations & Feedback
 
 We expect some apps will need some features that are not currently available:

example/pages/ssr-auth-required.js

@@ -46,6 +46,10 @@ export const getServerSideProps = withAuthUserTokenSSR({
   // `getServerSideProps`, including redirects.
   // https://nextjs.org/docs/basic-features/data-fetching#getserversideprops-server-side-rendering
   const token = await AuthUser.getIdToken()
+
+  // Note: you shouldn't typically fetch your own API routes from within
+  // `getServerSideProps`. This is for example purposes only.
+  // https://github.com/gladly-team/next-firebase-auth/issues/264
   const endpoint = getAbsoluteURL('/api/example', req)
   const response = await fetch(endpoint, {
     method: 'GET',