Automated material management workflows fail due to expired API tokens

ERP Workday
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1

Our automated material request workflows started failing yesterday with authentication errors. We have Python scripts that run every 4 hours to process material requisitions through Workday API, but they’re now returning 401 Unauthorized.

Error from logs:


HTTP 401: Token validation failed
WWW-Authenticate: Bearer error="invalid_token"
Timestamp: 2025-03-14 18:45:12

The scripts use OAuth2 tokens that we refresh periodically, but the refresh flow seems broken. We’re checking if the scope requirements changed or if there’s an issue with our token refresh logic. The automation has been running fine for 8 months until now.

Anyone experienced similar API token expiration issues with material management workflows? We need to understand the proper token refresh mechanism and OAuth2 scope configuration.

system 2

Here’s the complete solution addressing all three key areas:

API Token Refresh Flow: Workday implements OAuth2 token rotation where BOTH access and refresh tokens are replaced during refresh. Your script must persist the new refresh token from the response, not just the access token. The refresh response includes:


{
  "access_token": "new_access_token",
  "refresh_token": "new_refresh_token",
  "expires_in": 3600
}

Store both values immediately after each refresh.

Automation Script Logic: Update your Python script to handle token rotation properly:

  1. Before each API call, check if access token expires within 5 minutes
  2. If yes, call refresh endpoint with current refresh token
  3. Parse response and update BOTH access_token AND refresh_token in your credential store
  4. Retry the original API call with new access token
  5. Implement retry logic with exponential backoff (2s, 4s, 8s delays)

OAuth2 Scope Requirements: For material management workflows, verify your API client has these scopes assigned in Workday:

  • System: ‘Workday_Inventory_Management’ (required for material requisitions)
  • Integration: ‘Workday_Integration_System’ (for API access)

To fix immediately:

  1. Go to Workday > Register API Client for Integrations
  2. Find your client, verify scopes include material management
  3. Click ‘Manage Refresh Tokens’ > ‘Regenerate’ to get fresh tokens
  4. Update your script to store both tokens from refresh responses
  5. Add monitoring to alert 7 days before refresh token expiry (180-day default)

Implement token persistence in a secure credential vault, not flat files. This prevents similar issues and maintains security compliance for automated workflows.

This draft is based on general Workday knowledge. It has not been verified against your specific version and environment. Practitioners: verify the steps and share your experience below.

3

Check your refresh token expiration first. Workday refresh tokens have a 6-month validity by default, and if yours were issued 8 months ago, they’ve expired. You’ll need to re-authorize the integration client to get new tokens. Also verify your OAuth2 scopes haven’t been revoked in the API Client settings.

annacoder 4

Confirmed this resolves our Workday OAuth2 failures—persisting the new refresh token from the rotation response in our Python script eliminated all expired token errors in our material management automation.

5

I’ve seen this pattern before. The 401 error typically means your access token expired and the refresh attempt failed. In R1-2024, Workday tightened OAuth2 validation. Your script probably isn’t handling the refresh token rotation properly - when you refresh, you get BOTH a new access token AND a new refresh token. If you’re not storing the new refresh token, your next refresh attempt will fail. Check if your automation script logic updates both tokens after each refresh cycle.

6

Thanks for the insights. I checked and we are storing the new access token but NOT the new refresh token. That explains why it worked initially but failed after the first refresh cycle expired. Do I need to re-register the API client completely or can I just update the token handling in the script?

7

You don’t need to re-register. Just re-authorize once to get fresh tokens, then fix your script. Make sure you’re also requesting the correct scopes - material management requires ‘Workday_Inventory_Management’ scope at minimum. If your original registration didn’t include all necessary scopes, the tokens won’t work even if properly refreshed. Review your API client configuration in Workday to confirm scope assignments match your workflow requirements.

8

One more thing - implement exponential backoff for your refresh attempts. If the refresh fails, don’t hammer the endpoint every 4 hours. Wait progressively longer between retries and send alerts when refresh fails. This prevents your client from getting rate-limited, which makes the problem worse.

9

Adding to the previous responses - set up monitoring for token expiry BEFORE it happens. We implemented a check that alerts us 7 days before refresh token expiration so we can proactively re-authorize if needed.