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Affirm

Affirm Authorization API

Server-side operations for authorizing Affirm transactions after a customer completes the checkout flow and a checkout token is returned.

Documentation Provider Profile APIs.io OpenAPI GitHub

Affirm Authorization API is one of 11 APIs that Affirm publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Authorization. The published artifact set on APIs.io includes an OpenAPI specification.

This API exposes 3 operations across 3 paths, and defines 3 schemas. It is described by OpenAPI 3.2.0, at version 1.0.

Requests are made against 2 base URLs: https://api.affirm.com/api/v1, https://sandbox.affirm.com/api/v1.

3 operations 3 paths 3 schemas 1 GET2 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
1.0
Base URL
https://api.affirm.com
Authentication
HTTP Basic
Contact
Affirm Developer Support
Terms of Service
View terms
Resource Areas
1

Authentication & Security 1

Affirm Authorization API declares 1 security scheme for authenticating requests. It accepts HTTP basic authentication (basicAuth). By default, every request must be authenticated.

  • basicAuth — HTTP Basic Authentication using the merchant's public API key as the username and private API key as the password, Base64-encoded as per RFC 7617.

Paths & Operations 3

Across 3 paths, the API surfaces 3 operations — 1 GET, 2 POST. Each is listed below with its method, path, parameters, and response codes.

Authorization 3

Server-side operations for authorizing Affirm transactions after a customer completes the checkout flow and a checkout token is returned.

POST
/transactions
Affirm Authorize a Transaction
authorizeDirectTransaction body → 200400401
POST
/files
Affirm Upload a File
uploadFile body → 200400401
GET
/files/{id}
Affirm Download a File
downloadFile 1 param → 200401404

Schemas 3

The contract defines 3 schemas that model the data the API accepts and returns. The most detailed are Transaction (9 properties), FileObject (6 properties), Error (3 properties). Each schema is shown below with its type and property counts.

FileObject
object
Represents a file uploaded to Affirm's servers.
6 properties
Error
object
Standard error response returned by the Affirm API.
3 properties
Transaction
object
Represents an Affirm payment transaction at any point in its lifecycle.
9 properties

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

affirm-authorization-api-openapi.yml Raw ↑

Other APIs Affirm publishes across the network.

Affirm Checkout API
AE Profile APIs.io
Affirm Charges API
AE Profile APIs.io
Affirm Transactions API
AE Profile APIs.io
Affirm Cards API
AE Profile APIs.io
Affirm Checkouts API
AE Profile APIs.io
Affirm Disputes API
AE Profile APIs.io
Affirm Promos API
AE Profile APIs.io
Affirm Settlement Events API
AE Profile APIs.io
Affirm Transaction Events API
AE Profile APIs.io
Affirm Transactions API
AE Profile APIs.io
#Authorization
← Back to A APIs
API Details
ID
affirm:affirm-authorization-api
Base URL
https://api.affirm.com
Docs
https://docs.affirm.com/developers
Provider
Affirm
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