Trying to attach a user_id to the webhook payload

[benkimbuilds]

On my frontend, I have authenticated users with user_id. I want to attach this data through the checkout link flow so that the webhook receives the user_id and can associate it in my database to the payment object I'm storing.

Any ways to do this?

I've tried url query params, prefilling customer_name as user_id, and attaching metadata json objects to no success.

[rishi-raj-jain]

Can you share if https://docs.polar.sh/api-reference/webhooks/order.paid webhook includes the detail of the customer (i.e. email, in the customer object) that has fulfilled the purchase? and if you can use the email in your webhook logic to perform the desired action?

[benkimbuilds]

It's being sent, and it has the correct email field. I wasn't looking at this one - I was looking at checkout.updated / created.

Regardless, it would be really convenient to pass one field through the flow - userId. There are some authentication considerations when it comes down to using email only to verify payments, as well as the fact that some users will not have an associated email (sms verification)

[rishi-raj-jain]

I see. Can you share if passing that userId while creating the checkout session in the metadata body parameter allows that be received in the metadata property of the checkout.updated webhook?

[benkimbuilds]

I've tried that in the form of something like:

https://buy.polar.sh/{POLAR_ID}?customer_email=${user.email}&metadata={data}

but wasn't seeing it in the webhook payload

[rishi-raj-jain]

Unfortunately, with that way, it won't be possible. You'd need to send it as a body parameter instead of as a query parameter. Example:

curl --request POST \
  --url https://api.polar.sh/v1/checkouts/ \
  --header 'Authorization: Bearer polar_oat_...' \
  --header 'Content-Type: application/json' \
  --data '{
  "allow_discount_codes": true,
  "require_billing_address": false,
  "is_business_customer": false,
  "metadata": {
    "userId": "my_unique_key"
  }
}'

Does that clarify?