Required Information

Minimum Data to Send to the API

Quite a bit of information has been collected from the customer by your application to process the credit card transaction. Depending on the input and output formats and the transmission method used, it is possible that all the information will not be required.

Merchant/400 API Parameters.

Each of the parameters defined for the WwwMrcSubmit API call is required in one form or another. The Remote Host Name, Remote Host Name Length and Remote Port Number parameters are critical for the API to know where to send the request. The Transmission Method, Input Data Format and Output Data Format parameters tell the API how to function, both from the standpoint of the transaction stream and in how it interfaces with the data you have supplied. The other parameters contain information for the API to process or will be returned with results data from the card processor and the API.

It is important to keep in mind that, while some parameters are considered output (returning data from the API) to the calling application, it is still a minimum requirement that they be defined as a placeholder where the API will insert the return data.

Fields in the pSubmitInputs Input Structure.

Customer, order, and credit card information is passed to the Merchant/400 API via the pSubmitInputs parameter. Depending on the transmission method to be used, some of the fields are required and some are not.

WWWMERCH_INPUT1 structure fields required for MERCH_METHOD1:

WWWMERCH_INPUT1 structure fields required for MERCH_METHOD2: WWWMERCH_INPUT2 structure fields required for MERCH_METHOD3:

Fields in the pSubmitResults Output Structure.

The results of the transaction (success or failure) are received from the Merchant/400 API via the pSubmitResults parameter. Here again, the transmission method could play a part in the fields that are required. Currently, the fields required in the WWWMERCH_RESULT1 structure are identical when using either transmission method.

WWWMERCH_RESULT1 structure fields required:

The Bytes Provided field should contain a value large enough to accommodate the other fields in the structure, including space for the Return Comment field. Return Comment should be large enough to receive any comments that might be anticipated coming from the API or the card processor. This is where you will receive information about why the transaction failed and may be integral in determining a course of action for your application (retry the transaction later) or for your customer (call their bank or credit card agency). The actual text is usually determined by the card processor or partner agency.