Currently, I'm using the following third-party libraries to integrate with Braintree:
But I'm not able to find any method to save card details. Is there a rest API call available to save card details?
Full disclosure: I work at Braintree. If you have any further questions, feel free to contact support.
Both of the third-party libraries you linked to are wrappers for our client SDKS and have documentation that show that you will need to return the resulting payment method nonce to your server-side to use. A payment method nonce is a secure, one-time-use reference to payment information. It's the key element that allows your server to communicate sensitive payment information to Braintree without ever touching the raw data.
Braintree does not have a REST API at this moment, however you can use one of our server SDKS to run a Customer Create API Call, which will save that customer's payment information into the Braintree Vault. Additionally, you could run a Payment Method Create API Call as well to save the card details.
