Back

Solera • Shipped 2024

eBay, from SOAP to REST

SOAP

<Fault/>

REST

200 OK

Role

Software Development Engineer I

Timeline

2023 — 2024

Team

Cross-functional

Skills

C#

.NET

SOAP

REST

eBay Trading API

SQL

Overview

eBay was deprecating their calls.

They just never mentioned it.

At my time in Solera, one of our most interesting projects was migrating the eBay calls from their SOAP API to REST. eLink — the product I was in charge of then — kept listings, orders, and inventory in sync with eBay.

This was a C# client generated from the Trading API WSDL, and every call was an XML envelope. I led the migration to REST. Same operations, but JSON instead of XML envelopes. Status codes instead of a Fault sitting inside a 200.

Why

A 200 that still means the call failed.

If you have ever handled XML and SOAP calls, you know what I am talking about. Rate limits arrived as XML error structures and faults instead of status codes. Tokens can expire mid-batch. Warning Acks looked like success until you filtered the SeverityCode.

The after

The cutover.

Me and my team moved the callers one operation at a time. We put a single interface in front of listings, orders, and inventory so the rest of eLink did not care whether SOAP or REST was underneath. Both clients ran against the same SKUs. We compared payloads, logged the mismatches, and only cut the WSDL when REST was the only writer and the catalog still matched.