FusionAuth developer image
FusionAuth developer logo
  • Back to site
  • Expert Advice
  • Blog
  • Developers
  • Downloads
  • Account
  • Contact sales
Navigate to...
  • Welcome
  • Getting Started
  • 5-Minute Setup Guide
  • Release Notes
  • Core Concepts
    • Overview
    • Users
    • Roles
    • Groups
    • Entity Management
    • Registrations
    • Applications
    • Tenants
    • Identity Providers
    • Key Master
    • SCIM
    • Search
    • Authentication and Authorization
    • Integration Points
    • Localization and Internationalization
    • Editions and Features
    • Roadmap
  • Installation Guide
    • Overview
    • System Requirements
    • Server Layout
    • Cloud
    • Cluster
    • Docker
    • Fast Path
    • Kubernetes
      • Overview
      • Deployment Guide
      • Minikube Setup
      • Amazon EKS Setup
      • Google GKE Setup
      • Microsoft AKS Setup
    • Kickstart™
    • Homebrew
    • Packages
    • Database
    • FusionAuth App
    • FusionAuth Search
    • Common Configuration
  • Admin Guide
    • Overview
    • Config Management
    • Licensing
    • Monitoring
    • Proxy Setup
    • Securing
    • Technical Support
    • Troubleshooting
    • Upgrading
  • Migration Guide
    • Overview
    • General
    • Auth0
    • Keycloak
    • Amazon Cognito
    • Tutorial
  • APIs
    • Overview
    • Authentication
    • Errors
    • Actioning Users
    • API Keys
    • Applications
    • Audit Logs
    • Connectors
      • Overview
      • Generic
      • LDAP
    • Consents
    • Emails
    • Entity Management
      • Overview
      • Entities
      • Entity Types
      • Grants
    • Event Logs
    • Families
    • Forms
    • Form Fields
    • Groups
    • Identity Providers
      • Overview
      • Links
      • Apple
      • External JWT
      • Epic Games
      • Facebook
      • Google
      • HYPR
      • LinkedIn
      • Nintendo
      • OpenID Connect
      • SAML v2
      • SAML v2 IdP Initiated
      • Sony PlayStation Network
      • Steam
      • Twitch
      • Twitter
      • Xbox
    • Integrations
    • IP Access Control Lists
    • JWT
    • Keys
    • Lambdas
    • Login
    • Message Templates
    • Messengers
      • Overview
      • Generic
      • Kafka
      • Twilio
    • Multi-Factor/Two Factor
    • Passwordless
    • Reactor
    • Registrations
    • Reports
    • SCIM
      • Overview
      • SCIM EnterpriseUser
      • SCIM Group
      • SCIM Service Provider Config.
      • SCIM User
    • System
    • Tenants
    • Themes
    • Users
    • User Actions
    • User Action Reasons
    • User Comments
    • Webhooks
  • Client Libraries
    • Overview
    • Dart
    • Go
    • Java
    • JavaScript
    • .NET Core
    • Node
    • OpenAPI
    • PHP
    • Python
    • Ruby
    • Typescript
  • Themes
    • Overview
    • Examples
    • Helpers
    • Localization
    • Template Variables
  • Email & Templates
    • Overview
    • Configure Email
    • Email Templates
    • Email Variables
    • Message Templates
  • Events & Webhooks
    • Overview
    • Writing a Webhook
    • Securing Webhooks
    • Events
      • Overview
      • Audit Log Create
      • Event Log Create
      • JWT Public Key Update
      • JWT Refresh
      • JWT Refresh Token Revoke
      • Kickstart Success
      • User Action
      • User Bulk Create
      • User Create
      • User Create Complete
      • User Deactivate
      • User Delete
      • User Delete Complete
      • User Email Update
      • User Email Verified
      • User IdP Link
      • User IdP Unlink
      • User Login Failed
      • User Login Id Duplicate Create
      • User Login Id Duplicate Update
      • User Login New Device
      • User Login Success
      • User Login Suspicious
      • User Password Breach
      • User Password Reset Send
      • User Password Reset Start
      • User Password Reset Success
      • User Password Update
      • User Reactivate
      • User Registration Create
      • User Registration Create Complete
      • User Registration Delete
      • User Registration Delete Complete
      • User Registration Update
      • User Registration Update Complete
      • User Registration Verified
      • User Two Factor Method Add
      • User Two Factor Method Remove
      • User Update
      • User Update Complete
  • Example Apps
    • Overview
    • Dart
    • Go
    • Java
    • JavaScript
    • .NET Core
    • PHP
    • Python
    • Ruby
  • Lambdas
    • Overview
    • Apple Reconcile
    • Client Cred. JWT Populate
    • Epic Games Reconcile
    • External JWT Reconcile
    • Facebook Reconcile
    • Google Reconcile
    • HYPR Reconcile
    • JWT Populate
    • LDAP Connector Reconcile
    • LinkedIn Reconcile
    • Nintendo Reconcile
    • OpenID Connect Reconcile
    • SAML v2 Populate
    • SAML v2 Reconcile
    • SCIM Group Req. Converter
    • SCIM Group Resp. Converter
    • SCIM User Req. Converter
    • SCIM User Resp. Converter
    • Sony PSN Reconcile
    • Steam Reconcile
    • Twitch Reconcile
    • Twitter Reconcile
    • Xbox Reconcile
  • Identity Providers
    • Overview
    • Apple
    • Epic Games
    • External JWT
      • Overview
      • Example
    • Facebook
    • Google
    • HYPR
    • LinkedIn
    • Nintendo
    • OpenID Connect
      • Overview
      • Azure AD
      • Discord
      • Github
    • Sony PlayStation Network
    • Steam
    • Twitch
    • Twitter
    • SAML v2
      • Overview
      • ADFS
    • SAML v2 IdP Initiated
      • Overview
      • Okta
    • Xbox
  • Messengers
    • Overview
    • Generic Messenger
    • Kafka Messenger
    • Twilio Messenger
  • Connectors
    • Overview
    • Generic Connector
    • LDAP Connector
    • FusionAuth Connector
  • Self Service Account Mgmt
    • Overview
    • Updating User Data & Password
    • Add Two-Factor Authenticator
    • Add Two-Factor Email
    • Add Two-Factor SMS
    • Customizing
    • Troubleshooting
  • Advanced Threat Detection
    • Overview
  • Integrations
    • Overview
    • CleanSpeak
    • Kafka
    • Twilio
  • OpenID Connect & OAuth 2.0
    • Overview
    • Endpoints
    • Tokens
  • SAML v2 IdP
    • Overview
    • Google
    • Zendesk
  • Plugins
    • Plugins
    • Writing a Plugin
    • Custom Password Hashing
  • Guides
    • Overview
    • Advanced Registration Forms
    • Breached Password Detection
    • Multi-Factor Authentication
    • Multi-Tenant
    • Passwordless
    • Securing Your APIs
    • Silent Mode
    • Single Sign-on
  • Tutorials
    • Overview
    • User Control & Gating
      • Gate Unverified Users
      • Gate Unverified Registrations
      • User Account Lockout
    • Setup Wizard & First Login
    • Register/Login a User
    • Start and Stop FusionAuth
    • Authentication Tokens
    • Key Rotation
    • JSON Web Tokens
    • Prometheus Setup
    • Switch Search Engines
    • Two Factor (pre 1.26)
  • Reference
    • CORS
    • Configuration
    • Data Types
    • Known Limitations
    • Password Hashes

    External JWT Reconcile

    External JWT Reconcile lambda

    When an External JWT identity provider is used to complete a federated login request FusionAuth will use the email address to reconcile user. You may optionally utilize a lambda to customize the user and user registration during this authentication event.

    When you create a new lambda using the FusionAuth UI we will provide you an empty function for you to implement.

    If you are using the API to create the lambda you will need to ensure your function has the following signature:

    function reconcile(user, registration, jwt)  {
      // Lambda code goes here
    }

    This lambda must contain a function named reconcile that takes three parameters. The parameters that the lambda is passed are:

    • user - the FusionAuth User object

    • registration - the FusionAuth UserRegistration object

    • jwt - the JSON payload returned by the external identity provider JWT

    The two FusionAuth objects are well documented here in the User API and Registration API documentation. The jwt may contain various user claims to utilize during the reconcile process.

    Assigning the lambda

    Once a lambda is created, you may assign it to the External JWT identity provider in the IdP configuration.

    Navigate to Settings → Identity Providers and select your existing External JWT configuration or click Add provider and select External JWT if it has not yet been configured.

    Example lambda

    The following is a simple example of an External JWT reconcile lambda. You will need to modify it to suit your needs.

    // This is an example External JWT reconcile, modify this to your liking.
    function reconcile(user, registration, jwt) {
      // User claims
      user.firstName = jwt.first_name;
      user.lastName = jwt.last_name;
      user.birthDate = jwt.birth_date;
      user.imageUrl = jwt.image_url;
    
      user.data = user.data || {};
      user.data['email'] = jwt.email;
    
      // Registration claims
      registration.data = registration.data || {};
      registration.data['iss'] = jwt.iss;
    }

    Feedback

    How helpful was this page?

    See a problem?

    File an issue in our docs repo

    © 2021 FusionAuth
    Subscribe for developer updates