Azure Active Directory B2C User flow sign up sign in customization using API connector

I want to use Azure AD B2C in Azure APIM application.

Here, when user signs up, its details will be sent to admin/specific email id via email to review/approve that user. till that time, signed up user will get message after sign up and if he tried to sign in as - Your profile is in review, please wait for confirmation email and then try to sign in.
when admin/user will approve that user, then he will get confirmation email and he will be able to sign in.

Here, in above scenario, how can I use sign up and sign in user flow with API connector to achieve this.

please help.

Solution

This would not be supported with User Flows and API Connectors.

If you use the before creating the user API connector, if you return a 409 from your API, the user will not be created, therefore does not flow into the approval process. If you return a 200OK and mark the account as inactive via the Graph API the user will still be signed-in as part of the sign-up flow.

Returning a 409 response from the before sending the token (preview) API connector results in a AADB2C90075 error being sent to the application.

To reduce the overhead of developing against the Identity Experience Framework, I would suggest to have only a sign-in User Flow and manage the sign-up via an invitation based flow. This does mean handling the account request and approval outside of Azure AD B2C.