Cannot call the PayPal Sync API due to Authorization Failure - paypal

Question

I'm trying to use the relatively new PayPal Sync API to download my PayPal transactions. I'm following the Sync API guide. I started by logging into the PayPal Developer Dashboard My Apps & Credentials page, scrolling to the REST API apps section, creating an app, clicking on it, and enabling Transaction Search for both the Sandbox and Live accounts.
I then used the Sandbox account's Client ID and Secret to generate an Access Token. I confirmed that the Client ID and Secret are correct and active. My cURL command is below (note that I'm using cURL on Windows 10):
curl -v https://api.sandbox.paypal.com/v1/oauth2/token ^
-H "Accept: application/json" ^
-H "Accept-Language: en_US" ^
-u "<my-client-id>:<my-secret>" ^
-d "grant_type=client_credentials"
I received a response similar to the following (I added the formatting):
{
"scope":"https://uri.paypal.com/services/reporting/search/read
https://api.paypal.com/v1/payments/.*
https://uri.paypal.com/services/applications/webhooks
openid",
"nonce":"2018-04-04T02:20:02Z...",
"access_token":"<my-access-token>",
"token_type":"Bearer",
"app_id":"<my-app-id>",
"expires_in":32400
}
I then took the Access Token and copied it into the sample command on the Sync API guide page. Here is the command I ran:
curl -v -X GET https://api.sandbox.paypal.com/v1/reporting/transactions?transaction_id=5TY05013RG002845M&fields=all&page_size=100&page=1 ^
-H "Content-Type: application/json" ^
-H "Authorization: Bearer <my-access-token>"
I received the following error response:
< HTTP/1.1 401 Unauthorized
...
< Content-Length: 244
< Connection: close
< Content-Type: application/json
<
{
"name":"AUTHENTICATION_FAILURE",
"message":"Authentication failed due to invalid authentication credentials or a missing Authorization header.",
"links":[{
"href":"https://developer.paypal.com/docs/api/overview/#error",
"rel":"information_link"
}]
}
I tried many things to correct this error, including:
Adding a "Accept: application/json" and "Accept-Language: en_US" header to the command.
Creating a new Secret and generating a new Access Token.
Creating a new App with a new Client ID & Secret and generating a new Access Token.
Disabling Transaction Search, re-enabling it, and sending the command again.
Trying in the Live account.
Each of these attempts produced the same result. I noted that in the scope section of the access token response that it doesn't include a path similar to the stated path for the Sync API (/v1/reporting/transactions). However, that's just an observation, and I'm not sure if that is relevant.
I read through the entire Sync API guides and documentation about five times, and I searched Google and StackOverflow pretty thoroughly. I'm seeing evidence that some people are getting past the initial connection to Sync API, so I'm fairly certain this API works.
Can someone help me understand what I'm missing? Could it just be that I need to wait a day or two for their systems to catch up? PayPal's Developer documentation is not very user-friendly, and their Developer Dashboard is extremely glitchy.

Answer 1

I had this same issue. Putting double quotes around the URL solved it for me. The other API endpoints worked (authentication, authorizations/xyz) because they didn't have any special URL characters in them. In the transaction search, the query string delimiters were being parsed by Bash.
Your curl lines above become:
curl -v -X GET "https://api.sandbox.paypal.com/v1/reporting/transactions?transaction_id=5TY05013RG002845M&fields=all&page_size=100&page=1" \
-H "Content-Type: application/json" \
-H "Authorization: Bearer <my-access-token>"
Hope that helps someone.

Answer 2

It appears that this error may be caused by either cURL or the way I'm using it. On a hunch, I used Hurl.it to execute this sample request, and the request was successful (HTTP 200). I then tried another request where I searched for all transactions in a given date range, and that was also successful. I'm going to mark the question answered.