Starting a Session with Wallet Payments

Introduction

Developers can now start a session using the user wallet as a source of payment. eDRV's session handles the rest seamlessly.

📘

Availability Regions

The organization will be required to create and configure a stripe account and it is only available in the US at the moment.

Starting a Session

Developers can start a session by calling the POST /sessions API with an additional property type = wallet.

{
    "type": "wallet",
    "connector": "63d3a7662a035a1c9ac1356e",
    "user": "603763d392204c0c840578be"
}

Error Conditions
eDRV checks the user's wallet before a session can be started. The following error responses can be expected:

a. 405 Invalid user Wallet
If the user does not have a wallet, the API will return aUser does not have a wallet error with a 405 status code.
b. 405 Insufficient Minimum Balance
The user needs to have a minimum balance >= organization.configurations.session (by default this is set to 2000) to start a session otherwise, the API will return User does not have minimum balance error with 405 status code.
c. 405 Wallet/Connector Currency mismatch
If the connector.rate.currency is not the same as wallet.currency, eDRV will return a Wallet currency does not match the rate currency error with 405 status code.

Successful Session Attempt
If the checks above succeed, eDRV will attempt to start a charging session with payment.type = api_wallet, payment.authorized_amount = wallet.balance and payment.status = authorized. (eDRV will also send payment.created and payment_authorized webhook events along with session.created)

{
  "_id": "63dcf32e7d291b1b005284ac",
  "payment": {
    "_id": "63dcf32e7d291b1b005284aa",
    "session": "63dcf32e7d291b1b005284ac",
    "currency": "usd",
    "authorized_amount": 160.72,
    "type": "api_wallet",
    "status": "authorized",
    "createdAt": "2023-02-03T11:42:38.440Z",
    "updatedAt": "2023-02-03T11:42:38.440Z"
  },
  "type": "wallet",
  "user": "603763d392204c0c840578be",
  "chargestation": "63dccb1691f36e2e26c478b5",
  "connector": "63d3a7662a035a1c9ac1356e",
  "status": "created",
  "createdAt": "2023-02-03T11:42:38.682Z",
  "updatedAt": "2023-02-03T11:42:38.682Z"
}

On Session End
When the session ends, the payment.status will be updated to succeeded and a payment.captured webhook will be sent along with wallet.updated.

Pausing a Session

Developers can pause or resume an ongoing session by calling the following APIs. (All OCPP-compliant chargestations ought to support this feature).

• The GET /sessions/:id/pause API will stop the energy flow and trigger a session.paused webhook event.
• The GET /sessions/:id/resume API will start the energy flow and trigger a session.resumed webhook event.

Ending a Session

There is no API to stop a session when the rate attached to a session has a PARKING_TIME component in which case, it can only be stopped in the following two scenarios.

1. The user/driver detaches the cable from the charging station.
2. When the session.cost.amount is about to exceed payment.authorized_amount eDRV's session intelligence will attempt to stop an ongoing session to ensure the authorized_amount is never exceeded.

If the session does not have a PARKING_TIME rate component, it can be stopped by calling the sessions/:id/stop API.

Once the session ends (as reported by the charging station):

• A session.ended webhook event will be triggered which will have the final cost of the session.
• The system will try to update the wallet balance based on the final session cost and will send session.payment.captured webhook event.

📘

No Session Stops via API when using Overstay Rates

If a session is running on a Rate that has a PARKING_TIME component then you cannot use the Stop API.
In order to accurately calculate the amount of time a driver "overstayed", the session must not be stopped via the API (in this case, the driver removing the connector triggers the charge station to stop the session).