Lockbox Providers

Mail Uploads

Lockbox providers upload batches of mail items to Chariot using presigned URLs. See the Get a Mailbox Upload URL API reference for endpoint details.

Also see: Batch Format | Provisioning

Upload Process

1

Prepare the batch

Create a ZIP file containing TIFF images and a CSV index file. See the Batch Format guide for the expected format and examples.

2

Request a presigned upload URL

Send a request to the Chariot API:

POST /mailbox/upload_url
1{
2  "location_id": "po_543"
3}

Returns:

1{
2  "url": "https://chariot-lockbox-uploads.s3.us-east-1.amazonaws.com/provider_id/location_id/2026/03/16/12/01jf7x8m9n0p1q2r3s4t5u6v.zip"
3}
3

Upload the batch

Upload the ZIP file via PUT request to the returned URL:

$curl -X PUT -T batch.zip "https://chariot-lockbox-uploads.s3.us-east-1.amazonaws.com/provider_id/location_id/2026/03/16/12/01jf7x8m9n0p1q2r3s4t5u6v.zip"

Rescans

When a mail item requires a rescan, Chariot will send a request via email to the lockbox provider with the following information:

  • The provider’s ID of the mail item that requires a rescan
  • The location ID (or PO box) that the mail item was sent to

Once received, the lockbox provider should re-upload the batch using the same process as above, with one additional parameter: rescan = true.

POST /mailbox/upload_url
1{
2  "location_id": "po_543",
3  "rescan": true
4}

Notes

  • The batch must include both the rescanned TIFF image(s) and the standard CSV index file
  • The CSV must contain only the line items for the rescanned mail item
  • The CSV must use the same mail_item_id (described in the Batch Format guide) as the original submission so Chariot can match the rescan to the original data