EPAS Client Library

The EPAS Client Library is intended to greatly simply the task of ECR developers who are integrating their product with Westpay terminals.

Ready to start ?

Then simply read the documentation and download the latest release.

Background

The EPAS protocol defines a large and complex protocol for the interaction between payment terminals and ECRs. The protocol is:

• A very large protocol. The original specification document is 635 pages long.

• The EPAS specification doesn't cover all that is needed for a payment terminal solution so standards-breaking customisations are unavoidable.

• EPAS clients traditionally have to understand;

  • The XML contents of the EPAS messages
  • The sequencing of EPAS messages
  • The rules of EPAS messages
  • What messages are supported in the terminal
  • What message customisations are in place in the terminal
  • How to connect to the terminal and how to maintain the connection

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The EPAS Client Library

• .Net library, written in C#
• Allows much quicker EPAS integration
• No need to:
  • Understand XML
  • Parse message contents
  • Deal with connectivity
  • Understand customisations to the EPAS protocol
  • Handle message sequencing
• Easier for Westpay to support, compared to raw XML
• Makes Westpay terminals more attractive to integrators

---

But how much can it help?

Go from this

<SaleToPOIRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="EpasSaleToPOIMessages.xsd">
  <MessageHeader MessageClass="Service" MessageCategory="Payment" MessageType="Request" ServiceID="3305" WorkstationID="" POIID="80000091" />
  <PaymentRequest>
    <SaleData OperatorID="">
      <SaleTransactionID TransactionID="3021" TimeStamp="2021-02-09T11:24:02.5304374+00:00" />
    </SaleData>
    <PaymentTransaction>
      <AmountsReq Currency="SEK" RequestedAmount="59" CashBackAmount="0" />
      <TransactionConditions AllowChipXpress="true" WaitCardRemoval="false" DisableTip="false" DisableBankAxept="false" />
    </PaymentTransaction>
    <PaymentData PaymentType="Normal" />
  </PaymentRequest>
</SaleToPOIRequest>

<?xml version="1.0" encoding="utf-8"?>
<SaleToPOIResponse>
  <MessageHeader ProtocolVersion="1.0" MessageClass="Service" MessageCategory="Payment" MessageType="Response" ServiceID="3305" WorkstationID="" POIID="80000091" />
  <PaymentResponse>
    <Response Result="Success" />
    <POIData>
      <POITransactionID TransactionID="000009103009" TimeStamp="2021-02-09T12:24:21.5+01:00" />
    </POIData>
    <PaymentResult PaymentType="Normal">
      <AmountsResp AuthorizedAmount="59.00" />
    </PaymentResult>
  </PaymentResponse>
</SaleToPOIResponse>

To this

mEpas.Purchase(59.00, out TransactionResponse tr)

View the introduction wiki to find out more

EPAS Client Library Introduction Wiki

Or read our documentation:

[https://westpay.github.io/EPAS-Client-Library/]