Require Input Claims From JWT From RelyingParty in Azure AD B2C - azure-ad-b2c

Question

I'm sending hidden claims to B2C via a JWT following the WingTig Games demo code. How do I require claim(s) to be sent by the relying party? And if they are not sent, prevent the sign-up process? And provide my own error message to the user? These fields will be hidden from the user.
I tried adding required in my leaf policy in the RelyingParty node but it let me through. I tried adding required to my TechnicalProfile node but it let me through.
<InputClaims>
<InputClaim ClaimTypeReferenceId="extension_my_claim" Required="true"/>
</InputClaims>

Answer 1

As a workaround, you can add pre-condition to steps 1&2 then add additional step with your customer error page.
In the XML snippet below, I have added pre-conditions that run the steps 1&2 only if your claim exists, otherwise skip to the next step.
On sept 3, the pre-condition is run only if the claims does not exist, then display custom page. It’s just an example, in your case you can add your own error page.
<OrchestrationStep Order="1" Type="CombinedSignInAndSignUp" ContentDefinitionReferenceId="api.signuporsignin">
<Preconditions>
<Precondition Type="ClaimsExist" ExecuteActionsIf="false">
<Value>{your claim name}</Value>
<Action>SkipThisOrchestrationStep</Action>
</Precondition>
</Preconditions>
<ClaimsProviderSelections>
<ClaimsProviderSelection TargetClaimsExchangeId="FacebookExchange" />
<ClaimsProviderSelection ValidationClaimsExchangeId="LocalAccountSigninEmailExchange" />
</ClaimsProviderSelections>
<ClaimsExchanges>
<ClaimsExchange Id="LocalAccountSigninEmailExchange" TechnicalProfileReferenceId="SelfAsserted-LocalAccountSignin-Email" />
</ClaimsExchanges>
</OrchestrationStep>
<!-- Check if the user has selected to sign in using one of the social providers -->
<OrchestrationStep Order="2" Type="ClaimsExchange">
<Preconditions>
<Precondition Type="ClaimsExist" ExecuteActionsIf="false">
<Value>{your claim name}</Value>
<Action>SkipThisOrchestrationStep</Action>
</Precondition>
</Preconditions>
<Precondition Type="ClaimsExist" ExecuteActionsIf="false">
<Value>registrationSource</Value>
<Action>SkipThisOrchestrationStep</Action>
</Precondition>
</Preconditions>
<ClaimsExchanges>
<ClaimsExchange Id="FacebookExchange" TechnicalProfileReferenceId="Facebook-OAUTH" />
<ClaimsExchange Id="SignUpWithLogonEmailExchange" TechnicalProfileReferenceId="LocalAccountSignUpWithLogonEmail" />
</ClaimsExchanges>
</OrchestrationStep>
<!-- Error message-->
<OrchestrationStep Order="3" Type="ReviewScreen" ContentDefinitionReferenceId="api.selfasserted">
<Preconditions>
<Precondition Type="ClaimsExist" ExecuteActionsIf="true">
<Value>registrationSource</Value>
<Action>SkipThisOrchestrationStep</Action>
</Precondition>
</Preconditions>
</OrchestrationStep>
<!-- Rest of the UserJourney -->
</OrchestrationSteps>
</UserJourney>
Locate the <ContentDefinitions> element, and add following XML
<ContentDefinition Id=" api.inputtoken.error ">
<LoadUri>~/tenant/default/selfAsserted.cshtml</LoadUri>
<RecoveryUri>~/common/default_page_error.html</RecoveryUri>
<DataUri>urn:com:microsoft:aad:b2c:elements:selfasserted:1.1.0</DataUri>
<Metadata>
<Item Key="DisplayName">Collect information from user page</Item>
</Metadata>
</ContentDefinition>
Change the LoadUri value to point to your HTML error page