fastapi-code-generator
Generate a FastAPI application from an OpenAPI document.
📣 💼 Maintainer update: Open to opportunities. 🔗 koxudaxi.dev
Documentation
The docs site is the source of truth for user-facing documentation:
Use this README as a quick start. The full examples, templating details, and development workflow live in docs/.
Installation
uv tool install fastapi-code-generator
pip install fastapi-code-generator
Quick Start
fastapi-codegen --input openapi.yaml --output app --output-model-type pydantic_v2.BaseModel
fastapi-code-generator uses datamodel-code-generator to build the model layer. See the overview guide for a complete end-to-end example, custom templates, custom visitors, and router generation.
Command Help Snapshot
This block is generated from the current CLI so the README and docs overview stay aligned. For tested option scenarios and examples, use the CLI reference page.
Usage: fastapi-codegen [OPTIONS]
Options:
-e, --encoding TEXT [default: utf-8]
-i, --input TEXT [required]
-o, --output PATH [required]
-m, --model-file TEXT
-t, --template-dir PATH
--model-template-dir PATH
--enum-field-as-literal [all|one|none]
-r, --generate-routers
--specify-tags TEXT
-c, --custom-visitor PATH
--disable-timestamp
--strict-nullable Respect explicit OpenAPI nullable flags when
generating models.
--include-request-argument Auto-inject a FastAPI Request parameter into
operations when not present.
--allow-remote-refs / --no-allow-remote-refs
Allow or block fetching remote $ref targets
over HTTP/HTTPS. The default follows
datamodel-code-generator compatibility
behavior.
--allow-private-network Allow trusted remote $ref targets on local
or private network addresses.
-d, --output-model-type [pydantic_v2.BaseModel|pydantic_v2.dataclass|dataclasses.dataclass|typing.TypedDict|msgspec.Struct]
[default: pydantic_v2.BaseModel]
-p, --python-version [3.10|3.11|3.12|3.13|3.14]
[default: 3.10]
-V, --version
--use-annotated Use typing.Annotated for generated model
field constraints.
--reuse-model Reuse identical generated models as the same
type.
--enable-faux-immutability Generate frozen Pydantic models so instances
are hashable when their fields are hashable.
--install-completion Install completion for the current shell.
--show-completion Show completion for the current shell, to
copy it or customize the installation.
--help Show this message and exit.
Common Tasks
- Generate a single-file app from an OpenAPI spec:
fastapi-codegen --input openapi.yaml --output app - Generate router modules for larger applications:
fastapi-codegen --input openapi.yaml --output app --template-dir modular_template --generate-routers - Limit router regeneration to specific tags:
fastapi-codegen --input openapi.yaml --output app --template-dir modular_template --generate-routers --specify-tags "Wild Boars, Fat Cats" - Target Pydantic v2 output:
fastapi-codegen --input openapi.yaml --output app --output-model-type pydantic_v2.BaseModel
Further Reading
- Overview for the full walkthrough and generated output example
- CLI Reference for option-by-option behavior and tested scenarios
- Supported Formats for the generated support matrix
- Development & Contributing for the local workflow and docs maintenance steps
1 maintainer
Release files for fastapi-code-generator 0.8.1
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| fastapi_code_generator-0.8.1.tar.gz | 61.4 kB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| fastapi_code_generator-0.8.1-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 92.0 kB
Release files / fastapi_code_generator-0.8.1.tar.gz
| Download URL | fastapi_code_generator-0.8.1.tar.gz |
|---|---|
| Size | 61.4 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
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Transparency logRelease files / fastapi_code_generator-0.8.1-py3-none-any.whl
| Download URL | fastapi_code_generator-0.8.1-py3-none-any.whl |
|---|---|
| Size | 30.6 kB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
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Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.7
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 1, 2026.
Transparency log
