Overview

On October 2, 2023 Amazon rolled out a significant update to the Selling Partner API (SP‑API). Version 2.0 of the Java and C# SDKs eliminates the need for AWS Identity and Access Management (IAM) roles and AWS Signature Version 4 (SigV4) signing. Sellers and developers can now connect to SP‑API with a single OAuth 2.0 bearer token, cutting onboarding time and reducing maintenance.

Key Points

• No IAM Required — The new SDKs drop the IAM role creation step, allowing developers to skip the AWS console and policy setup.
• SigV4 Removed — Requests are no longer signed with SigV4; the SDK handles authentication automatically.
• SDK 2.0 Released — Updated Java and C# libraries now manage token acquisition, request headers, and error handling out of the box.
• Simplified Onboarding — Sellers can start using SP‑API endpoints with fewer prerequisites, speeding time to market.
• Backward Compatibility — Existing integrations built on older SDKs continue to function while migrating to the new version.

How the Feature Works

1. OAuth 2.0 Token Retrieval — The SDK calls getAccessToken(), exchanging a stored refresh token for a short‑lived bearer token that authenticates every request.
2. Automatic Header Injection — Once the token is obtained, the SDK attaches it to the HTTP Authorization header for all API calls, eliminating manual SigV4 signing.
3. Endpoint Calls — Developers invoke high‑level SDK methods (e.g., GetOrders, ListInventory, SubmitFeed) without constructing raw HTTP requests.
4. Built‑in Retries & Error Parsing — The SDK retries transient errors automatically and converts SP‑API error responses into structured exceptions for easier debugging.

Context Section

• Before: A fulfillment system had to create an IAM user, attach a policy granting SP‑API permissions, and sign every HTTP request with SigV4. Custom signing helpers and secure storage of IAM credentials were required in the deployment pipeline.