Preview your SDK

Once you configure your SDK, you can preview the generated SDK code using Fern’s CLI.

Simply append the --preview flag to the command used to generate the SDK and you will see the generated code populated in a .preview folder within your fern folder.

Custom Code

If you have added custom code to your SDK, --preview will preserve those changes.

Here’s an example of how you can preview your SDK:

Generator configuration

generators.yml

1 api: 
2   path: ./path/to/openapi.yml
3 groups:
4   python-sdk:
5     generators:
6       - name: fernapi/fern-python-sdk
7         version: 3.0.0
8         output:
9           location: pypi
10           package-name: imdb
11           token: ${PYPI_TOKEN}
12         github:
13           repository: imdb/imdb-python
14         config:
15           client_class_name: imdb

Invoke the Fern CLI

$ fern generate --group python-sdk --preview

Preview your SDK

The resulting folder structure will look like this:

OpenAPI

Fern Definition

$ fern/
>   ├─ fern.config.json
>   ├─ .preview/
>     └─ fern-python-sdk/
>       └─ ...
>   ├─ generators.yml
>   └─ openapi/
>     └─ openapi.yml

1	api:
2	path: ./path/to/openapi.yml
3	groups:
4	python-sdk:
5	generators:
6	- name: fernapi/fern-python-sdk
7	version: 3.0.0
8	output:
9	location: pypi
10	package-name: imdb
11	token: ${PYPI_TOKEN}
12	github:
13	repository: imdb/imdb-python
14	config:
15	client_class_name: imdb

$	fern/
>	├─ fern.config.json
>	├─ .preview/
>	└─ fern-python-sdk/
>	└─ ...
>	├─ generators.yml
>	└─ openapi/
>	└─ openapi.yml