Vendor Extensions

Here is a list of vendor extensions used by different generators.

The list may not be up-to-date so the best way is to look for "x-" in the mustache templates.

(All examples are in YAML format)

All

x-generate-alias-as-model

The schema (array or map) will be generated as a model

ArrayOfStringModel:
  x-generate-alias-as-model
  type: array
  items:
    type: string

ObjC

x-objc-operationId

To customize the method name, you can provide a different name in x-objc-operationId, e.g.

summary: Add a new pet to the store
description: ''
operationId: addPet
x-objc-operationId: CreateNewPet

Java (Feign)

x-accepts

A single Accepts value as the Feign API client needs a single value for Accepts header, e.g.

consumes:
  - application/json
  - application/xml
x-accepts: application/json

x-content-type

A single "Content-Type" value as the Feign API client needs a single value for Content-Type header, e.g.

produces:
  - application/xml
  - application/json
x-content-type: application/json

Java (okhttp-gson)

x-group-parameters

Group parameters into a single object. x-group-parameters can be put at the top level of the spec or in each endpoint definition.

PHP (client)

x-group-parameters

Group parameters into a single object. x-group-parameters can be put at the top level of the spec or in each endpoint definition.

Rust-server

x-responseId

Each response may specify a unique x-responseId. rust-server will use this to name the corresponding enum variant in the code. e.g.

paths:
  /ping:
    get:
      responses:
        200:
          description: OK
          x-responseId: Pong

MySQL Schema

x-mysqlSchema

MySQL schema generator creates vendor extensions based on openapi dataType and dataFormat. When user defined extensions with same key already exists codegen accepts those as is. It means it won't validate properties or correct it for you. Every model in definitions can contain table related and column related extensions like in example below:

definitions:
  Order:
    description: This should be most common InnoDB table
    type: object
    properties:
      id:
        description: >-
          This column should be unsigned BIGINT with AUTO_INCREMENT
        type: integer
        format: int64
        x-mysqlSchema:
          columnDefinition:
            colName: id
            colDataType: DECIMAL
            colDataTypeArguments:
              - argumentValue: 16
                isString: false
                hasMore: true
              - argumentValue: 4
                isString: false
                hasMore: false
            colUnsigned: true
            colNotNull: true
            colDefault:
              defaultValue: AUTO_INCREMENT
              isString: false
              isNumeric: false
              isKeyword: true
            colComment: >-
              Column comment. This column should be unsigned BIGINT with AUTO_INCREMENT
    x-mysqlSchema:
      tableDefinition:
        tblName: orders
        tblStorageEngine: InnoDB
        tblComment: >-
          Table comment. This should be most common InnoDB table

❗ There are properties that are not implemented by now(tblStorageEngine), but you can see how generator can be enhanced in future.

Protocol Buffer Schema

x-protobuf-index

For assigning field numbers: https://developers.google.com/protocol-buffers/docs/proto3#assigning_field_numbers

PowerShell

x-powershell-method-name

To customize the method name in the PowerShell client, e.g.

x-powershell-method-name: Invoke-CustomMethod

Swift

x-swift-hastable

To extends the model with Hashable, e.g.

public struct Pet: Codable {

becomes

public struct Pet: Codable, Hashable {