Authenticate to the Sierra REST API using the client credentials grant
domain: techdocs.iii.com · 4 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Obtain a Sierra API client key/secret from Sierra's admin API client key management
Base64-encode 'key:secret' and send it in an HTTP Basic Authorization header
POST to /iii/sierra-api/v6/token with Content-Type application/x-www-form-urlencoded and body grant_type=client_credentials
Store the returned access_token and send it as a Bearer token on subsequent v6 API calls
Known gotchas
Access tokens expire after 3,600 seconds (60 minutes) and must be refreshed rather than treated as long-lived
The client key must be granted specific role permissions (e.g., Patrons Write) in Sierra admin; authenticated calls to unauthorized resources return 403
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