Uniquely identifying transfers
Increase's money movement APIs include an optional creation parameter called unique_identifier
. This string parameter should be a unique value you pre-allocate in your system before invoking the Transfer creation method.
You cannot re-use a unique_identifier
across two transfers. If you attempt to create a second transfer with an already used unique_identifier
, you'll receive an HTTP 409 Conflict error with the type
field set to unique_identifier_already_exists_error
and the resource_id
set to the ID of the Transfer that is associated with the unique_identifier
.
You can fetch a Transfer by its unique_identifier
by using the List endpoint and filtering with the optional parameter unique_identifier
. This returns a list containing either the one matching Transfer or an empty list.
Transfers always include their unique_identifier
when fetching or listing them from the Increase API. If you want to associate a Transfer with a specific Invoice, Order, or Payment in your systems, we recommend including the ID in your system as the unique_identifier
attribute at Increase.
Recovering from errors
If you receive an HTTP 400, HTTP 500, or connection error when creating a Transfer, you can use the unique_identifier
field to automatically recover from the error. You have several options:
- It's safe to retry a request that may have failed if you set the
unique_identifier
parameter in both the initial call and the second attempt. If the original transfer request was successful, the second attempt will result in a descriptive error that includes the ID of the created object. - A system or operator can fetch a Transfer by its
unique_identifier
and determine if the object was created at Increase and what itsid
is.
A unique_identifier
persists forever, so this information is never lost and retries are always safe. This is different from Increase's Idempotency-Key
HTTP Header, which is more useful for intermittent connection issues and automatic library-level retries.
Supported transfer types
- Account Transfers
- ACH Transfers
- Check Transfers
- Real-Time Payments Transfers
- Wire Transfers