Azure B2C Custom Policy - Showing button on validation - azure

Question

It looks like there is not a lot of help and forums on the Azure B2C Custom policy framework.
I have used the following technical profile for my custom policy.
<TechnicalProfile Id="AAD-UserReadUsingEmailAddress">
<Metadata>
<Item Key="Operation">Read</Item>
<Item Key="RaiseErrorIfClaimsPrincipalDoesNotExist">true</Item>
<Item Key="UserMessageIfClaimsPrincipalDoesNotExist">An account could not be found for the provided user ID.</Item>
</Metadata>
<IncludeInSso>false</IncludeInSso>
<InputClaims>
<InputClaim ClaimTypeReferenceId="email" PartnerClaimType="signInNames.emailAddress" Required="true" />
</InputClaims>
<OutputClaims>
<!-- Required claims -->
<OutputClaim ClaimTypeReferenceId="objectId" />
<OutputClaim ClaimTypeReferenceId="authenticationSource" DefaultValue="localAccountAuthentication" />
<OutputClaim ClaimTypeReferenceId="strongAuthenticationPhoneNumber" />
<!-- Optional claims -->
<OutputClaim ClaimTypeReferenceId="userPrincipalName" />
<OutputClaim ClaimTypeReferenceId="displayName" />
<OutputClaim ClaimTypeReferenceId="accountEnabled" />
<OutputClaim ClaimTypeReferenceId="otherMails" />
<OutputClaim ClaimTypeReferenceId="signInNames.emailAddress" />
</OutputClaims>
<OutputClaimsTransformations>
<OutputClaimsTransformation ReferenceId="AssertAccountEnabledIsTrue" />
</OutputClaimsTransformations>
<IncludeTechnicalProfile ReferenceId="AAD-Common" />
</TechnicalProfile>
This profile looks for the user and comes back with an error message if the user was not found in AD. However I want to show the user a button to sign up after the validation happens. How can I achieve this?
Any help will be appreciated!

Answer 1

Azure AD B2C Custom Policy is now a GA product and it has a lot of good documentation available.
What you want to achieve here very common and has been explained in starter pack. Its called a signuporsignin policy.
Walk through the article
https://learn.microsoft.com/en-us/azure/active-directory-b2c/active-directory-b2c-get-started-custom
You can also see the policies here
https://github.com/Azure-Samples/active-directory-b2c-custom-policy-starterpack/blob/master/SocialAndLocalAccountsWithMfa/TrustFrameworkBase.xml
Look at this technical profile https://github.com/Azure-Samples/active-directory-b2c-custom-policy-starterpack/blob/master/SocialAndLocalAccountsWithMfa/TrustFrameworkBase.xml#L981
providing this metadata might help
<Metadata>
<Item Key="SignUpTarget">SignUpWithLogonEmailExchange</Item>
<Item Key="setting.operatingMode">Email</Item>
<Item Key="ContentDefinitionReferenceId">api.selfasserted</Item>
</Metadata>