fly-io SSO API

openapi: 3.2.0
info:
  title: Fly.io Extensions Apps SSO API
  description: The Fly.io Extensions API is a provider-facing HTTP interface that enables third-party services to integrate with the Fly.io platform as extension providers.
  version: '1.0'
  contact:
    name: Fly.io Extensions Program
    url: https://fly.io/docs/reference/extensions_api/
  termsOfService: https://fly.io/legal/terms-of-service/
servers:
- url: https://{provider_base_url}
  description: Provider-hosted API server. Each extension provider hosts their own implementation of this API at a URL they register with Fly.io.
  variables:
    provider_base_url:
      default: api.example.com
      description: The base URL registered by the extension provider with Fly.io.
- url: https://api.fly.io
  description: Fly.io platform server for OAuth and webhook endpoints.
security:
- flySharedSecret: []
tags:
- name: SSO
  description: Single sign-on operations allowing Fly.io users to access provider dashboards using their Fly.io credentials via OAuth.
paths:
  /extensions/{extension_id}/sso:
    get:
      operationId: initiateSso
      summary: Initiate SSO for an extension
      description: Called by Fly.io when a user runs a flyctl command to access the provider's dashboard (e.g., flyctl ext redis dashboard). The provider should verify the request signature and redirect the user to the appropriate dashboard page, using information from the Fly.io OAuth token to identify the user.
      tags:
      - SSO
      parameters:
      - $ref: '#/components/parameters/extensionId'
      responses:
        '302':
          description: Redirect to the provider's dashboard.
          headers:
            Location:
              description: URL of the provider dashboard for this extension resource.
              schema:
                type: string
                format: uri
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
components:
  schemas:
    ErrorResponse:
      type: object
      description: A standard error response.
      properties:
        error:
          type: string
          description: Human-readable error message.
        status:
          type: integer
          description: HTTP status code.
  responses:
    NotFound:
      description: The requested extension resource was not found.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
    Unauthorized:
      description: Missing or invalid authentication credentials.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
  parameters:
    extensionId:
      name: extension_id
      in: path
      description: The unique identifier of the extension resource, as returned by the provider.
      required: true
      schema:
        type: string
  securitySchemes:
    flySharedSecret:
      type: http
      scheme: bearer
      description: Shared secret provided by Fly.io to the extension provider. Fly.io includes this secret in an Authorization Bearer header on all requests to the provider's API for verification.
    oauthBearerAuth:
      type: http
      scheme: bearer
      description: Fly.io OAuth access token obtained from the token exchange endpoint.
    webhookHmac:
      type: apiKey
      in: header
      name: X-Fly-Signature
      description: HMAC-SHA256 signature of the raw request body, computed using the webhook signing secret. Recipients must verify this signature before processing the payload.
externalDocs:
  description: Fly.io Extensions API Documentation
  url: https://fly.io/docs/reference/extensions_api/