Fastly

Fastly Backend API

Operations for managing backends (origin servers) that a Fastly service routes requests to.

Documentation GitHub OpenAPI

Operations 5

GET /service/{service_id}/version/{version_id}/backend List backends #

POST /service/{service_id}/version/{version_id}/backend Create a backend #

GET /service/{service_id}/version/{version_id}/backend/{backend_name} Get a backend #

PUT /service/{service_id}/version/{version_id}/backend/{backend_name} Update a backend #

DELETE /service/{service_id}/version/{version_id}/backend/{backend_name} Delete a backend #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Fastly VCL Services Backend API
  description: The Fastly VCL Services API provides programmatic access to configure Varnish Configuration Language (VCL) objects that power most Fastly services. Developers can upload custom VCL code or use the API to generate VCL through configuration objects including backends, conditions, cache settings, request settings, response objects, headers, and VCL snippets. This API is central to defining how Fastly processes, routes, and caches HTTP requests at the edge.
  version: '1.0'
  contact:
    name: Fastly Support
    url: https://support.fastly.com
  termsOfService: https://www.fastly.com/terms
servers:
- url: https://api.fastly.com
  description: Fastly API Production Server
security:
- apiKeyAuth: []
tags:
- name: Backend
  description: Operations for managing backends (origin servers) that a Fastly service routes requests to.
paths:
  /service/{service_id}/version/{version_id}/backend:
    get:
      operationId: listBackends
      summary: List backends
      description: Retrieves a list of all backends configured for a specific version of a Fastly service.
      tags:
      - Backend
      parameters:
      - $ref: '#/components/parameters/serviceId'
      - $ref: '#/components/parameters/versionId'
      responses:
        '200':
          description: Successfully retrieved the list of backends.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Backend'
        '401':
          description: Unauthorized. The API token is missing or invalid.
    post:
      operationId: createBackend
      summary: Create a backend
      description: Creates a new backend for a specific version of a Fastly service. Backends define the origin servers that Fastly routes requests to.
      tags:
      - Backend
      parameters:
      - $ref: '#/components/parameters/serviceId'
      - $ref: '#/components/parameters/versionId'
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              $ref: '#/components/schemas/Backend'
      responses:
        '200':
          description: Successfully created the backend.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Backend'
        '400':
          description: Bad request. Missing or invalid parameters.
        '401':
          description: Unauthorized. The API token is missing or invalid.
  /service/{service_id}/version/{version_id}/backend/{backend_name}:
    get:
      operationId: getBackend
      summary: Get a backend
      description: Retrieves the details of a specific backend for a version of a Fastly service.
      tags:
      - Backend
      parameters:
      - $ref: '#/components/parameters/serviceId'
      - $ref: '#/components/parameters/versionId'
      - $ref: '#/components/parameters/backendName'
      responses:
        '200':
          description: Successfully retrieved the backend.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Backend'
        '401':
          description: Unauthorized. The API token is missing or invalid.
        '404':
          description: Backend not found.
    put:
      operationId: updateBackend
      summary: Update a backend
      description: Updates a specific backend for a version of a Fastly service.
      tags:
      - Backend
      parameters:
      - $ref: '#/components/parameters/serviceId'
      - $ref: '#/components/parameters/versionId'
      - $ref: '#/components/parameters/backendName'
      requestBody:
        content:
          application/x-www-form-urlencoded:
            schema:
              $ref: '#/components/schemas/Backend'
      responses:
        '200':
          description: Successfully updated the backend.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Backend'
        '401':
          description: Unauthorized. The API token is missing or invalid.
        '404':
          description: Backend not found.
    delete:
      operationId: deleteBackend
      summary: Delete a backend
      description: Deletes a specific backend from a version of a Fastly service.
      tags:
      - Backend
      parameters:
      - $ref: '#/components/parameters/serviceId'
      - $ref: '#/components/parameters/versionId'
      - $ref: '#/components/parameters/backendName'
      responses:
        '200':
          description: Successfully deleted the backend.
          content:
            application/json:
              schema:
                type: object
                properties:
                  status:
                    type: string
                    description: Confirmation status of the deletion.
        '401':
          description: Unauthorized. The API token is missing or invalid.
        '404':
          description: Backend not found.
components:
  parameters:
    backendName:
      name: backend_name
      in: path
      required: true
      description: The name of the backend.
      schema:
        type: string
    serviceId:
      name: service_id
      in: path
      required: true
      description: The alphanumeric string identifying the Fastly service.
      schema:
        type: string
    versionId:
      name: version_id
      in: path
      required: true
      description: The integer identifying the service version.
      schema:
        type: integer
  schemas:
    Backend:
      type: object
      description: A backend represents an origin server that a Fastly service routes requests to for content that is not cached at the edge.
      properties:
        name:
          type: string
          description: The name of the backend.
        address:
          type: string
          description: The hostname or IPv4 address of the backend.
        port:
          type: integer
          description: The port number on the backend.
          default: 80
        use_ssl:
          type: boolean
          description: Whether to use SSL/TLS to connect to the backend.
        ssl_hostname:
          type: string
          description: The hostname to verify for SSL certificate validation.
        ssl_cert_hostname:
          type: string
          description: The hostname to use when checking the backend certificate.
        ssl_sni_hostname:
          type: string
          description: The SNI hostname to use for the backend connection.
        shield:
          type: string
          description: The data center to use as a shield POP.
        weight:
          type: integer
          description: The weight assigned to this backend for load balancing.
          minimum: 1
          maximum: 100
        connect_timeout:
          type: integer
          description: Maximum duration in milliseconds to wait for a connection.
        first_byte_timeout:
          type: integer
          description: Maximum duration in milliseconds to wait for the first byte.
        between_bytes_timeout:
          type: integer
          description: Maximum duration in milliseconds to wait between bytes.
        max_conn:
          type: integer
          description: Maximum number of connections to the backend.
        healthcheck:
          type: string
          description: The name of the healthcheck to use with the backend.
        auto_loadbalance:
          type: boolean
          description: Whether to auto-load-balance this backend.
        request_condition:
          type: string
          description: The name of a condition to apply to route requests to this backend.
        comment:
          type: string
          description: A freeform descriptive note about the backend.
  securitySchemes:
    apiKeyAuth:
      type: apiKey
      in: header
      name: Fastly-Key
      description: API token used to authenticate requests to the Fastly API.
externalDocs:
  description: Fastly VCL Services API Documentation
  url: https://www.fastly.com/documentation/reference/api/vcl-services/