eBay

mooonwalk · ‎01-18-2025

Context
We’ve been trying to implement eBay’s OAuth 2.0 token exchange process to retrieve an access token using the authorization_code grant type. While we believe our setup is correct, we are consistently encountering a 500 Internal Server Error when calling the token endpoint.

The user is redirected back with a valid code parameter after successfully completing the login flow.
Token Exchange:

Content-Type: application/x-www-form-urlencoded
Authorization: Basic BASE64(client_id:client_secret)

Body (Form-data):

grant_type=authorization_code
code=DECODED_AUTHORIZATION_CODE
redirect_uri=YOUR_REGISTERED_REDIRECT_URI

Validation:

The following values were carefully validated before sending the request:
The client_id and client_secret are correct and Base64-encoded properly.
The code (authorization code) is correctly URL-decoded.
The redirect_uri matches the one registered in the Developer Portal exactly (case-sensitive).
The scopes used during the authorization flow are valid and match the API requirements.

What Happens
Despite following the process as outlined in eBay’s documentation, the response to the token exchange request is consistently:

HTTP Status Code 500 – Internal Server Error

<!doctype html><html lang="en"><head><title>HTTP Status 500 – Internal Server Error</title></head><body><h1>HTTP Status 500 – Internal Server Error</h1></body></html>

Troubleshooting Attempts
Confirmed All Parameter Values:

Verified the code, client_id, client_secret, and redirect_uri.
All are accurate and properly formatted.

Checked Expiry:

Ensured the authorization code was used within its 5-minute (299) validity period.
Tested in Sandbox and Production:

Same 500 error occurs in both environments.

Reviewed Documentation:

Followed eBay’s official OAuth documentation step-by-step.
Question

Is this a known issue with the OAuth token endpoint, or are there specific configurations we might be missing? If anyone has encountered this issue before, we would greatly appreciate any insights or solutions.

Thank you!

klickitat · ‎01-22-2025

Here's a working implementation in python. This does not produce 500 errors:

def ebay_callback():

code = request.args.get("code")

state = request.args.get("state")

if not code:

flash("Authorization failed.", "error")

return redirect(url_for("auth.login"))

auth_header = base64.b64encode(f"{CLIENT_ID}:{CLIENT_SECRET}".encode()).decode()

# Exchange authorization code for tokens

headers = {

"Content-Type": "application/x-www-form-urlencoded",

"Authorization": f"Basic {auth_header}",

}

data = {

"grant_type": "authorization_code",

"code": code,

"redirect_uri": RU_NAME,

}

response = requests.post("EBAY_TOKEN_URL=https://api.ebay.com/identity/v1/oauth2/token", headers=headers, data=data)

if response.status_code != 200:

flash("Token exchange failed.", "error")

return redirect(url_for("auth.login"))

token_data = response.json()

access_token = token_data["access_token"]

refresh_token = token_data["refresh_token"]

expires_in = token_data["expires_in"]

token_expiry = datetime.utcnow() + timedelta(seconds=expires_in)

# Save credentials to the database and redirect

...

View Best Answer in original post

elena5-0 · ‎01-20-2025

It sounds like you've done a thorough job troubleshooting the 500 Internal Server Error with eBay's OAuth 2.0 token exchange process. This error can be quite frustrating, especially when you've carefully validated all parameters.

Here are a few additional steps you might consider:

Check eBay's Documentation: Ensure you've followed all steps in eBay's official OAuth documentation. Sometimes, small details in the setup can cause issues.

Review Logs: Check the server logs for any additional error messages or details that might provide more insight into what's causing the error.

Test with Postman: Use Postman or a similar tool to manually send the token exchange request and see if you get more detailed error information.

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