API Versioning & lifecycle

The fulfillmenttools API is considered versionless. That means that our API evolves in a backward-compatible way. The following changes, are considered to be backward-compatible:

• Adding new API resources.

• Adding new optional request parameters to existing API methods.

• Adding new properties to existing API responses.

• Changing the order of properties in existing API responses.

• Adding values to enums (see Enum Handling)

All endpoints, fields, and types in our APIs have a lifecycle ranging from Alpha to Beta to GA (generally available). Additionally, we may deprecate certain functionality in our API.

We mark endpoints, types, fields, or features by their release life cycle. These are included as flags (see details in the corresponding sections). Consider the following example:

REST API

'/api/facilities/{facilityId}':
  get:
    operationId: getFacility
    summary: Get a facility with the given ID
    x-fft-api-lifecycle: ga
    responses:
      '200':
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Facility'

components:
  schemas: 
    Facility:
      properties:
        id:
          type: string
          x-fft-api-lifecycle: ga
        description:
          type: string
          x-fft-api-lifecycle: alpha

In this case, the facility endpoint and entity are both generally available. However, the description field is still under construction and may change. When working with the facility endpoint, ensure that the information provided in the description field is not integrated into any mission-critical components that may be sensitive to changes.

GraphQL API

In GraphQL, lifecycle information is implemented via schema directives. Schema directives except for @deprecated are not fetched during introspection. We recommend manually fetching the latest schema from our API hub.

type Query {
  facility(id: String!): Facility @FFTMetadata(lifecycle = GA)
  listings: ListingConnection @FFTMetadata(lifecycle = GA)
}

type Facility @FFTMetadata(lifecycle = BETA) {
  id: ID! @FFTMetadata(lifecycle = GA)
  name: String! @FFTMetadata(lifecycle = GA)
  description: String! @FFTMetadata(lifecycle = ALPHA)
  
  listings: ListingConnection @semanticNonNull @FFTMetadata(lifecycle = BETA)
}

type ListingsConnection @FFTMetadata(lifecycle = GA) {
  edges: [ListingEdge] @semanticNonNull(levels = [0,1]) @FFTMetadata(lifecycle = GA)
}

The above example shows a typical case for mixed lifecycle flags in our GraphQL schema. Querying a facility and its ID and name can be achieved using GA fields, which are fully covered under our SLAs. The same holds for listings, including filters like the facilityRef of the listing. However, querying all listings in a facility using Facility.listings, a non-GA field is not covered under the SLAs. Additionally, the description field is still under construction and may change. When working with the facility endpoint, ensure that the information provided in the description field is not integrated into any mission-critical components that may be sensitive to changes.

Lifecycle Overview

Lifecycle State	SLAs	Breaking changes	Change Notifications
Alpha	❌	common	no notifications
Beta	❌	rarely	no later than two weeks before breaking changes
GA	️✅	❎	-
Deprecated	️✅ if Endpoint was previously GA	❎ if Endpoint was previously GA	-

Alpha

Alpha endpoints are currently in development and might not be fully functional. Therefore, breaking changes (both semantic and syntactical) are common. We change these endpoints without communication. Additionally, alpha endpoints are not contained in our SLAs.

Please contact us if you want to use endpoints marked with the Alpha tag.

Alpha Flag

Beta

Endpoints with the Beta life cycle state are more mature but still under active development. We try to prevent breaking changes. Nevertheless, breaking changes are possible in rare cases. There already exists functionality at these endpoints, but we don't cover these in our SLAs. Breaking changes are communicated to clients two weeks before the change.

Please contact us if you want to use endpoints marked with the Beta tag.

Beta Flag

GA (General Availability)

Endpoints without any flag are production-ready and stable endpoints. We serve these endpoints within our SLAs.

Deprecated

In some cases, we might deprecate endpoints or attributes. Deprecated endpoints contain hints to new endpoints, replacing their functionality or providing a newer feature version. We monitor deprecated endpoints to ensure we only remove functionality when nobody uses it. Deprecated endpoints are still served within our SLAs if they had previously made it to GA.

Breaking Changes

When an endpoint is under active development (e.g., marked as Alpha or Beta), we might change its semantic and/or syntactic behavior. You will find Alpha or Beta flags on resources, types (or part of types), and other places under development. If you encounter such a flag, it means the following:

• This endpoint, type, or field might be subject to breaking changes.

• It might not be available at all times.

• It could disappear without specific warning.

• It currently does not fall under our SLA regulations.

Enum handling

Our schemas use plenty of enums, for example, for status use. Please be aware that adding a value to it is considered a nonbreaking change:

REST

OrderStatus:
  type: "string"
  enum:
    - "OPEN"
    - "CANCELLED"
    - "LOCKED"
+   - "CLOSED"

GraphQL

enum OrderStatus {
   OPEN
   CANCELLED
   LOCKED
+  CLOSED 
}

However, the tooling around this use of enumerations varies: A code generator will most likely produce enums that cannot contain values different from the one described. If you are handling enums, the best practice is to map unknown enum values to ones you recognize or that yield an error.