Fly.io Extensions API
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. When a Fly.io user provisions an extension via the flyctl CLI, Fly.io forwards the provisioning request to the provider's API with details about the requesting organization, and the provider responds with environment variable configuration that is attached to the target application.
Fly.io Extensions API is one of 9 APIs that Fly Io publishes on the APIs.io network, described by a machine-readable OpenAPI specification and an AsyncAPI event-driven specification.
Tagged areas include Extensions, Integration, Partner, Platform, and Provisioning. The published artifact set on APIs.io includes API documentation, an OpenAPI specification, and an AsyncAPI specification.
This API exposes 4 operations across 2 paths, and defines 4 schemas. It is described by OpenAPI 3.2.0, at version 1.0.
Requests are made against 2 base URLs: https://{provider_base_url}, https://api.fly.io.
Metadata
The identity and technical contract details declared by the specification.
Authentication & Security 3
Fly.io Extensions API declares
3 security schemes
for authenticating requests.
It accepts HTTP bearer tokens (flySharedSecret).
It accepts HTTP bearer tokens (oauthBearerAuth).
An API key is passed in the header as X-Fly-Signature (webhookHmac).
By default, every request must be authenticated.
flySharedSecret— 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…oauthBearerAuth— Fly.io OAuth access token obtained from the token exchange endpoint.webhookHmac— HMAC-SHA256 signature of the raw request body, computed using the webhook signing secret. Recipients must verify this signature before processing the payload.
Paths & Operations 4
Across 2 paths, the API surfaces 4 operations — 1 DELETE, 1 GET, 1 PATCH, 1 POST. Each is listed below with its method, path, parameters, and response codes.
Operations for provisioning, retrieving, and updating extension resource instances. Fly.io calls these endpoints on the provider's server when users interact with extensions via t…
Schemas 4
The contract defines 4 schemas that model the data the API accepts and returns. The most detailed are ProvisionRequest (10 properties), ExtensionResource (4 properties), ProvisionResponse (4 properties), ErrorResponse (2 properties). Each schema is shown below with its type and property counts.
Specification
The full machine-readable OpenAPI contract behind this narrative.
Source
More from Fly Io 8
Other APIs Fly Io publishes across the network.
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