# Transaction processing

{% hint style="info" %}
Please note this is not required for Sandbox customers as the default simulator will be used
{% endhint %}

This endpoint is used to submit transaction processing requests from Mypinpad to a customer transaction processing service. The customer response will contain the transaction response payload created by the Issuer, or in rare cases, the acquirer if the Issuer is unavailable and the acquirer has a stand in facility.

NOTE: The response of the API request does not reflect the result of transaction processing. It only indicates successful processing has taken place. So even though an Issuer may decline a transaction the result of the API call will be a 200 - success. To know if the transaction was approved by the Issuer you need to look at the EMV data. See the EMV standards and specifications for details.

If a transaction request results in a 500 being returned by the customer transaction processing service, the request may be resubmitted by the Mypinpad service.

If the customer transaction processing service received a response from the Issuer during the first call of the API (that received the 500 response), the customer transaction processing service must send the response that it should have sent in the first place. It must not process the transaction again. Identifiers in the request are used to identify previously processed transactions.

Note that at present, the Mypinpad service only supports OAuth2.0 for connectivity with customers for direct host integration option. The configuration should allow Mypinpad to: 

* **Add auth data** to **Request Headers**
* Use **Client Credentials** as **Grant types**
* **Send client credentials in body** for **Client Authentication**
* Use **Bearer** as **Header Prefix**

As such, customers needs to provide Mypinpad:

* Their transaction endpoint URL
* The client credentials for their OAuth2.0 platform (**Client ID** and **Client Secret**)
* The URL for their token endpoint (**Access Token URL**)
* The Scope of access request (if required)

## Submit transaction processing requests from Mypinpad to a customer transaction processing service.

{% openapi src="/files/xjhcu7DjWzSK6Bdb12We" path="https\://<customer-provided transaction endpoint URL>" method="post" %}
[AcquirerServiceTransactionPayload.json](https://1699189908-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fa85elt1hISy0Af3PGOpw%2Fuploads%2FRJmJCm94V7gZNLx2N8fx%2FAcquirerServiceTransactionPayload.json?alt=media\&token=fffd112d-5e90-44c0-b755-dc0b3814596f)
{% endopenapi %}


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