# Parse Server 8 Migration Guide <!-- omit in toc -->

This document only highlights specific changes that require a longer explanation. For a full list of changes in Parse Server 8 please refer to the [changelog](https://github.com/parse-community/parse-server/blob/alpha/CHANGELOG.md).

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- [Email Verification](#email-verification)
- [Database Indexes](#database-indexes)

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## Email Verification

In order to remove sensitive information (PII) from technical logs, the `Parse.User.username` field has been removed from the email verification process. This means the username will no longer be used and the already existing verification token, that is internal to Parse Server and associated with the user, will be used instead. This makes use of the fact that an expired verification token is not deleted from the database by Parse Server, despite being expired, and can therefore be used to identify a user.

This change affects how verification emails with expired tokens are handled. When opening a verification link that contains an expired token, the page that the user is redirected to will no longer provide the `username` as a URL query parameter. Instead, the URL query parameter `token` will be provided.

The request to re-send a verification email changed to sending a `POST` request to the endpoint `/resend_verification_email` with `token` in the body, instead of `username`. If you have customized the HTML pages for email verification either for the `PagesRouter` in `/public/` or the deprecated `PublicAPIRouter` in `/public_html/`, you need to adapt the form request in your custom pages. See the example pages in these aforementioned directories for how the forms must be set up.

> [!WARNING]
> An expired verification token is not automatically deleted from the database by Parse Server even though it has expired. If you have implemented a custom clean-up logic that removes expired tokens, this will break the form request to re-send a verification email as the expired token won't be found and cannot be associated with any user. In that case you'll have to implement your custom process to re-send a verification email.

> [!IMPORTANT]
> Parse Server does not keep a history of verification tokens but only stores the most recently generated verification token in the database. Every time Parse Server generates a new verification token, the currently stored token is replaced. If a user opens a link with an expired token, and that token has already been replaced in the database, Parse Server cannot associate the expired token with any user. In this case, another way has to be offered to the user to re-send a verification email. To mitigate this issue, set the Parse Server option `emailVerifyTokenReuseIfValid: true` and set `emailVerifyTokenValidityDuration` to a longer duration, which ensures that the currently stored verification token is not replaced too soon.

Related pull request:

- https://github.com/parse-community/parse-server/pull/8488

## Database Indexes

As part of the email verification and password reset improvements in Parse Server 8, the queries used for these operations have changed to use tokens instead of username/email fields. To ensure optimal query performance, Parse Server now automatically creates indexes on the following fields during server initialization:

- `_User._email_verify_token`: used for email verification queries
- `_User._perishable_token`: used for password reset queries

These indexes are created automatically when Parse Server starts, similar to how indexes for `username` and `email` fields are created. No manual intervention is required.

> [!WARNING]
> If you have a large existing user base, the index creation may take some time during the first server startup after upgrading to Parse Server 8. The server logs will indicate when index creation is complete or if any errors occur. If you have any concerns regarding a potential database performance impact during index creation, you could create these indexes manually in a controlled procedure before upgrading Parse Server.

Related pull request:

- https://github.com/parse-community/parse-server/pull/9893
