Canonical

Canonical Assertions API

The Assertions API from Canonical — 1 operation(s) for assertions.

Documentation GitHub OpenAPI

Operations 1

GET /v2/assertions/{type}/{primaryKey} Fetch an assertion

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OpenAPI Specification

openapi: 3.2.0
x-generated-from: documentation
x-provenance-note: >-
  Hand-authored by API Evangelist from the publicly documented Snap Store Device API
  reference at https://api.snapcraft.io/docs/ — NOT harvested from a Canonical-published
  machine-readable contract, because Canonical publishes none for api.snapcraft.io. Marked
  2026-09-05 so this file is never mistaken for a provider artifact. The specs Canonical does
  publish are the other thirteen documents in openapi/, each harvested verbatim.
info:
  title: Canonical Snap Store Device Assertions API
  description: 'Public Snap Store Device API (api.snapcraft.io) used by snap clients to

    discover snaps, fetch metadata, refresh installed snaps, search the

    store, and download assertions. Endpoints come from the publicly

    documented snap store reference (https://api.snapcraft.io/docs/).


    Most endpoints are open / unauthenticated. Authenticated endpoints under

    /api/v1/snaps/auth/ use Ubuntu One macaroons and require the

    Snap-Device-Series header.


    This specification is a best-effort, hand-authored representation. The

    Charmhub API (api.charmhub.io), Snapcraft Dashboard API, snapd local

    REST API, LXD REST API, MAAS API, Juju, Launchpad, Ubuntu Pro Client,

    and Landscape APIs are not modeled here — see apis.yml for those

    surfaces and their respective Canonical documentation.

    '
  version: v2
  contact:
    name: Canonical / Snapcraft
    url: https://api.snapcraft.io/docs/
servers:
- url: https://api.snapcraft.io
tags:
- name: Assertions
paths:
  /v2/assertions/{type}/{primaryKey}:
    parameters:
    - in: path
      name: type
      required: true
      schema:
        type: string
        enum:
        - snap-declaration
        - snap-revision
        - account
        - account-key
        - validation-set
    - in: path
      name: primaryKey
      required: true
      schema:
        type: string
    get:
      summary: Fetch an assertion
      description: Retrieve a signed assertion document by type and primary key.
      responses:
        '200':
          description: Signed assertion document (application/x.ubuntu.assertion).
          content:
            application/x.ubuntu.assertion:
              schema:
                type: string
      tags:
      - Assertions