User ID Mapping

tip

If you have not stored your user's Auth0 userId in your database you can ignore this section.

If you store your user's Auth0 userId in your tables you will need to map the user's Auth0 userId to their SuperTokens userId and override SuperTokens functions so the correct userId is used.

In this section we will go over:

• The functions used to set and retrive userId data used in the Modifications to login section,
• How to override the necessary SuperTokens functions to use the correct userId.

UserId Mapping functions

We will need the following two functions:

• setUserIdMapping()
• getUserIdMapping()

// The function is used in the Modifications to Login section to map a users newly created SuperTokens userIds with their Auth0 userIdlet setUserIdMapping = async (    input: {        auth0UserId: string,        supertokensUserId: string    }): Promise<void> => {    // set the mapping in your data store}
// The function retrieves the userId mapping using either the SuperTokens or Auth0 userId.let getUserIdMapping = async (    input: {        auth0UserId?: string,        supertokensUserId?: string    }): Promise<{ auth0UserId: string, supertokensUserId: string } | undefined> => {
    // get mapped userIds if the input userId exits in your data store    // getUserIdMappingIfExists is a function defined by you    let userIdMapping = getUserIdMappingIfExists(input)
    // if input userId exists get the mapped user data    if (userIdMapping !== undefined) {
        return ({ auth0UserId: userIdMapping.auth0UserId, supertokensUserId: userIdMapping.supertokensUserId })    }
    return undefined}

Overriding all functions on the backend which take userId as input or return userId in their response:

If a user has an Auth0 userId mapped to an SuperTokens userId, then:

• A SuperTokens function which has userId in its input should replace the Auth0 userId in the input object with the SuperTokens userId
• A SuperTokens function which returns userId in its response should replace the SuperTokens userId in the response object with the Auth0 userId

The following functions need to be modified so that the correct userId is used:

• getUserByEmail
• getUserById
• getUserByPhoneNumber
• updateUser

Nodejs

import Passwordless from "supertokens-node/recipe/passwordless";
let getUserIdMapping = async (    input: {        auth0UserId?: string,        supertokensUserId?: string    }): Promise<{ auth0UserId: string, supertokensUserId: string } | undefined> => {    // TODO: See previous step    return undefined;}
Passwordless.init({    flowType: "USER_INPUT_CODE_AND_MAGIC_LINK",    contactMethod: "EMAIL_OR_PHONE",    createAndSendCustomEmail: async (input, context) => {        // Handle sending email    },    createAndSendCustomTextMessage: async (input, context) => {        // Handle sending sms    },    override: {        functions: (originalImpl) => {            return {                ...originalImpl,                getUserByEmail: async function (input) {                    let response = await originalImpl.getUserByEmail(input)
                    if (response === undefined) {                        return undefined                    }
                    // get userId mapping if it exists                    let userIdMappingInfo = await getUserIdMapping({ supertokensUserId: response.id })
                    // set Auth0 userId in the response                    if (userIdMappingInfo !== undefined) {                        response.id = userIdMappingInfo.auth0UserId                    }
                    return response                },                getUserById: async function (input) {
                    // get userId mapping if it exists                    let userIdMappingInfo = await getUserIdMapping({ auth0UserId: input.userId })
                    if (userIdMappingInfo !== undefined) {                        // call original implementation with the mapped SuperTokens userId                        let response = await originalImpl.getUserById({                            userId: userIdMappingInfo.supertokensUserId,                            userContext: undefined                        })
                        if (response === undefined) {                            return response                        }
                        // set Auth0 userId in the response                        response.id = userIdMappingInfo.auth0UserId                        return response                    }
                    return await originalImpl.getUserById(input)                },                getUserByPhoneNumber: async function (input) {                    let response = await originalImpl.getUserByPhoneNumber(input)
                    if (response === undefined) {                        return response                    }
                    // get userId mapping if it exists                    let userIdMappingInfo = await getUserIdMapping({ supertokensUserId: response.id })
                    if (userIdMappingInfo !== undefined) {                        // set Auth0 userId in the response                        response.id = userIdMappingInfo.auth0UserId                    }
                    return response                },                updateUser: async function (input) {
                    // get userId mapping if it exists                    let userIdMappingInfo = await getUserIdMapping({ auth0UserId: input.userId })                    if (userIdMappingInfo !== undefined) {                        // set the mapped SuperTokens userId in the input                        input.userId = userIdMappingInfo.supertokensUserId                    }
                    return await originalImpl.updateUser(input);                }            }        }    },})