Generate transfer_subs from a list of apple_user_ids

genAppleTransfer.sh

#!/bin/bash
totalLines=0
requestTransfer() {
    transferSub=$(curl -sS --request POST $1 \
    --header 'Content-Type: application/x-www-form-urlencoded' \
    --header "Authorization: Bearer $2" \
    -d "sub=$3&target=$4&client_id=$5&client_secret=$6" \
    | jq -r '.transfer_sub')
    printf '%s,%s,%s,%s\n' "$7" "$8" "$9" "$transferSub"
}

generateTransferIdFunc() {
    APIURL="https://appleid.apple.com/auth/usermigrationinfo"
    recipientTeamId=THE_RECIPIENT_TEAM_ID
    senderAppBundleID=YOUR_APP_BUNDLE_ID
    senderSecret=YOUR_SENDER_SECRET

    bearerAuth=$(curl -sS --request POST 'https://appleid.apple.com/auth/token' \
        --header 'Content-Type: application/x-www-form-urlencoded' \
        --data-urlencode 'grant_type=client_credentials' \
        --data-urlencode 'scope=user.migration' \
        --data-urlencode "client_id=$senderAppBundleID" \
        --data-urlencode "client_secret=$senderSecret" \
        | jq -r '.access_token')

    i=0
    if [ $# -eq 1 ] && [ -f $1 ]
    then
        OLDIFS=$IFS
        IFS=","
        header=0
        while read id guid userid email
        do
            if [ $header -eq 0 ]
            then
                header=1
                printf "qxmd_id,guid,email,transfer_sub\n" > transfers.csv
                continue
            else
                requestTransfer $APIURL $bearerAuth $userid $recipientTeamId $senderAppBundleID $senderSecret $id $guid $email &
                ((i=i+1))
                if [ $i -eq 100 ]
                then
                    sleep 1
                    i=0
                fi
            fi
        done < $1 | pv -pt -s$totalLines >> transfers.csv
        IFS=$OLDIFS
    else
        echo "Input file not found!"
    fi
}

if [ $# -eq 1 ] && [ -f $1 ]
then
    totalLines=$(< "$1" wc -l)
    generateTransferIdFunc $1
else
    echo "Input file not found!"
fi

Hi Ethan - Thanks for sharing this code.
My team is currently in the same process and I was wondering whether you can help us with a question. When does the old private/relay email stops working? Is it as soon as we transfer the app or only after we generate the new information in the receiving account?