OpenAPI Generate Command

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Usage

# From a local file
apitwin generate --spec openapi.yaml --out ./mocks

# From a remote URL
apitwin generate --spec https://petstore3.swagger.io/api/v3/openapi.json --out ./mocks

# YAML format, single file instead of one per tag
apitwin generate --spec openapi.yaml --format yaml --split=false

Then serve immediately:

apitwin --config ./mocks

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What is generated

For each path + operation in the spec:

• One config file per tag (e.g. countries.toml, cities.toml) containing one route per operation
• One stub JSON file per response status code in stubs/
• OpenAPI path parameters ({id}) are converted to apitwin wildcards (*)
• The first 2xx response is set as the route fallback

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Example output

For the Petstore spec:

mocks/
├── pet.toml        # 13 routes
├── store.toml      #  3 routes
├── user.toml       #  3 routes
└── stubs/
    ├── get_pet_petId_200.json
    ├── get_pet_findByStatus_200.json
    ├── post_pet_200.json
    └── ... (42 more)

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Generated config example

pet.toml:

# Generated from openapi.yaml
# Tag: pet

# Returns pets based on status
[[routes]]
method   = "GET"
match    = "/pet/findByStatus"
enabled  = true
fallback = "success"

  [routes.cases.success]
  status = 200
  file   = "stubs/get_pet_findByStatus_200.json"

  [routes.cases.bad_request]
  status = 400
  file   = "stubs/get_pet_findByStatus_400.json"

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Flags

Flag	Short	Default	Description
--spec <file|url>	-s	—	OpenAPI spec file path or URL
--out <dir>	-o	mocks	Output directory for config and stubs
--format <fmt>	-f	toml	Config format: toml, yaml, json
--split		true	One file per tag; --split=false for a single file

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Using Task

task generate SPEC=openapi.yaml
task generate SPEC=https://petstore3.swagger.io/api/v3/openapi.json
task generate SPEC=openapi.yaml OUT=./petstore

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See also: Stub Quality | Quick Start | CLI Reference