Transaction endpoints


/tokenize	Add POST /tokenize to your checkout flow, and store the Flex token for later use.
/transmit	On successful transactions, queue POST /transmit.
/evaluate	On a declined transaction, POST /evaluate for Flex to analyze and rescue/decline it.
/outcome	POST /outcome to get the order status on async calls to /evaluate.

General information

The APIs are RESTful, they use HTTP methods (POST, PATCH, PUT, GET) to perform functions on objects.

Some requests include data in their message body, for example to define the attributes of the object being created or updated.

Endpoints


Sandbox testing	https://api-sandbox.flex-charge.com/v1/
Production environment	https://api.flex-charge.com/v1/

The sandbox is a completely isolated environment, so feel free to experiment. When you're ready to move to production, we will provide you production credentials and give you access to the live environment.

❗️
Real financial data cannot be used in the Sandbox.
Please use our whitelisted test credit cards.

Headers

To communicate with the Core API, you must include the proper headers in your API requests.

Request headers

You must include the following headers in requests sent to the Core API:

Name	Description	Request Type	Value
authorization	Any request must be authenticated.	GET, POST, PUT	Api key/Token
content-type	The media type of the resource	POST, PUT	application/json

Versioning

The Core API version is indicated in each endpoint resource path.

For example, https://api.flex-charge.com/v1/transmit indicates the API is at version 1.

Flex increments the version number when it releases a new version containing backwards-incompatible changes. Minor updates and bug fixes are typically released without incrementing the version number.

Ensure that your application handles API revisions by allowing for additional, unspecified resource fields in the response and for variable response sizes.

Errors

Use this list to diagnose failed transactions and fine-tune your exception-handling capabilities.

Error codes are based on HTTP response codes: the first three digits specify the HTTP response code, and the last three digits represent the error.

Response Code	Description
200 OK	Your request completed successfully.
201 Created	Resource created successfully.
204 No Content	Returned on a successful DELETE.
401 Unauthorized	Enter valid credentials to continue.
403 Forbidden	Access to the requested resource is denied.
405 Method Not Allowed	The method you supplied is not allowed for that resource, for example a PUT method on a read-only resource.
500 Internal Server Error	An error occurred that could not be handled by the application.
502 Bad Gateway	An invalid response was received by the server.
503 Service Unavailable	The server is temporarily unable to handle this request.
504 Gateway Timeout	The server timed out while attempting to complete this request.