High- Level Specification

Functional Overview

The purpose of this interface is to extract latest Exchange Rate data from the SAP ECC (PRS / PF2-client 050 ) and send to SAP Cloud Integration (CPI).

SAP Ariba and ICertis require Exchange Rates updated on a regular basis to carry out the business functions associated with Procurement business Processes. These two systems do not have a direct source for Exchange rates and this System Interface enables Exchange rates persisted in ECC to be synchronised with them.  SAP PRS receives an update 5 days a week from Reuters, and this System Interface extracts the Standard Exchange rates ( M rates ) from ECC tables after they are updated, normalises the rates by applying conversion factors, calculates inverse and cross rates, and then pushes the data to CPI. CPI then transforms the content to suite the receiver system specifications.

Scope and Objectives

This System Interface, a custom implementation in SAP ECC, sends:

• Selected list of Indirect, M type Exchange rates from TCURR table after applying any conversion factors - e.g. 1 EUR = 1.79230 AUD, 1 EUR = 1.17225 USD
• Direct rates calculated from the above - e.g. 1 AUD = 0.55794 EUR, 1 USD = 0.85306 EUR
• Cross rates for each of the Indirect rates - e.g. 1 AUD = 0.65404 USD, 1 USD = 1.52894 AUD

ECC carries out all rate calculations, so that there will be no discrepancies due to rounding . CPI is only responsible for routing and mapping to the target structures.

Process Flow Diagram

Assumptions

• The System Interface relies completely on the data available in TCURR. It is assumed that Reuters upload program manages any exceptions and errors
• The System Interface reads values applicable on the run date for each currency. It is assumed that the receiver system validates, if required, dates and currency codes that may differ from what's defined in respective systems
• The System Interface calculations will be rounded to a defined number of decimal points for consistency. It is assumed that Inverse and Cross rate calculations that may lead to minor differences in rounding are acceptable
• The System Interface will only extract the list of Currencies listed below

Dependencies

• This System Interface depends on the Exchange rates loaded via the existing BAU process. If the rates upload is missing, for example due to a public holiday, or an exception, this integration will continue to process the latest available rates.

Security, Integrity and Controls

• Required authorisations to execute the Program as a Background Job in ECC need to be defined.
• Existing secure connectivity for communication between SAP ECC and SAP CPI will be applied
• User role based authorisation will be applied to the Service hosted in CPI
• <TBC>Communication with CPI occurs through a secure RFC destination (type = H) defined in transaction SM59, using HTTPS with Basic Authentication </TBC>.

Configuration Requirements

• <To be discussed. If XI Proxy is used, then SOAMANAGER configuration is required.>

Special Requirements

• Ariba Exchange Rates have 10 decimal points and therefore the ECC output shall also adhere to this maximum to reduce rounding errors.

Design Rationale

The rationale of this System Interface is to provide a simple but reliable asynchronous flow of Exchange Rate data from SAP ECC to SAP CPI. The interface is implemented as a custom ABAP report that constructs and posts an XML payload directly to a CPI.

The program retrieves exchange rate data from standard SAP tables TCURR, but also uses data in other support tables like TCURF, and TCURV. The program selects only M rates, which are saved as indirect rates. For each rate, the system applies conversion factors and calculates the direct (inverse) rate, rounded to 10 decimal points. The output XML is structured in a flat format, reducing the need for further mapping or transformation in CPI.

The process is scheduled to run once daily, after the Reuters exchange rate upload job completes, ensuring that downstream systems such as SAP Ariba receive consistent and current financial rates aligned with ECC’s valuation dates.

API Use

There are no API use in this System Interface. The Interface uses a HTTP Service to push the data to CPI.

Data Structure

The output consists of a flat XML structure:

Schema File: ExchangeRateSchemaECC.xsd

Sample structure example in XML:

<?xml version="1.0" encoding="UTF-8"?>
<ExchangeRates xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <ExchangeRate>
        <FromCurrency>EUR</FromCurrency>
        <ToCurrency>USD</ToCurrency>
        <RateIdentifier>EUR:USD</RateIdentifier>
        <ValidFrom>2025-09-30</ValidFrom>
        <Rate>1.1743500000</Rate>
    </ExchangeRate>
    <ExchangeRate>
        <FromCurrency>USD</FromCurrency>
        <ToCurrency>EUR</ToCurrency>
        <RateIdentifier>USD:EUR</RateIdentifier>
        <ValidFrom>2025-09-30</ValidFrom>
        <Rate>0.8515348916</Rate>
    </ExchangeRate>
</ExchangeRates>

The following fields will be used to provide the required data structure of the interface: 

Calculation and Validation

Indirect Rate Mapping

Only "M" type rates are mapped

Direct (Inverse) Rate Mapping

Direct rates are calculated by taking the inverse of the Indirect rates calculated in the previous table. 

Cross Rate Mapping

This is required for all Indirect rates. Each of the Currency require a Cross with the other Currencies, as well as the inverse. 

Processing Logic

The list of Currencies to be extracted are found here: Currency_List_ERP_110.txt

1. Extract the rows with type M from TCURR that are valid for the run date
2. Sanitize the Rate value to remove the Indirect indicator, and apply the Conversion factors to get the normalised decimal value for the Indirect rate
3. Calculate the Inverse to get the Direct rate
4. For each Indirect Rate, calculate the Cross rate for each of the other Indirect Rates
5. Generate the payload in XML
6. Invoke the CPI service and pass the values for downstream processing

Delta or Full Load Requirements

The integration will upload all M rates valid for the date

Interface Alert & Monitoring

<TBC with BJ>

Language Requirements

No Language Requirements

User Interface Requirements

No User Interface Requirements

Volumetrics

Each Integration contain entries for all Indirect rates, their inverses, and cross rates with the other Indirect rates. At the moment there are 70 Exchange Rates in the Reuters file, therefore this Integration produces an output containing 4,970 rates.

Performance Consideration

<To be confirmed with BJ>

Error Handling

<To be confirmed with BJ>

Testing

How to Test

1. Schedule or run the Custom Program implemented by this Interface
2. Check in CPI that the Integration file has been received

Test Conditions and Expected Results

Test Considerations/Dependencies

Not Applicable

Other Information

Development Details

Package

Other Development Objects

Appendix

See also

Insert links and references to other documents which are relevant when trying to understand this decision and its implications. Other decisions are often impacted, so it's good to list them here with links. Attachments are also possible but dangerous as they are static documents and not updated by their authors.

Change log