Authenticate with Walmart Marketplace API using OAuth 2.0

domain: developer.walmart.com · 6 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗

Steps

  1. Register your application in the Walmart Developer Portal to obtain a client ID and client secret.
  2. POST to the token endpoint at https://marketplace.walmartapis.com/v3/token with Content-Type application/x-www-form-urlencoded and grant_type=client_credentials.
  3. Include a Basic Authorization header built from Base64-encoding YOUR_CLIENT_ID:YOUR_CLIENT_SECRET.
  4. Parse the JSON response for the access_token field and its expires_in value.
  5. Attach the token to subsequent API calls via the WM_SEC.ACCESS_TOKEN header.
  6. Refresh the token before expiry by repeating the POST; the old RSA signature scheme (WM_SEC.AUTH_SIGNATURE) was deprecated in 2019 and must not be used.

Known gotchas

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