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On this page
  • Configure SDK package settings
  • Generate a NuGet API key
  • Configure NuGet publication
  • Publish your SDK
Generators.NET

Publishing to NuGet

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Generating an SDK

Next

.NET configuration

Publish your public-facing Fern C#/.NET SDK to the NuGet registry. After following the steps on this page, you’ll have a versioned package published on NuGet.

Versioned package published on NuGet

This page assumes that you have:

  • An initialized fern folder, a GitHub repository for your C#/.NET SDK, and a C#/.NET generator group in generators.yml. See Generating an SDK (C#/.NET).

Configure SDK package settings

You’ll need to update your generators.yml file to configure the package name, output location, and client name for NuGet publishing. Your generators.yml should live in your source repository (or on your local machine), not the repository that contains your C#/.NET SDK code.

1

Configure output location

In the group for your C#/.NET SDK, change the output location from local-file-system (the default) to nuget to indicate that Fern should publish your package directly to the npm registry:

generators.yml
1groups: 
2  csharp-sdk:
3	generators:
4	  - name: fernapi/fern-csharp-sdk
5	    version: 2.65.0
6		output:
7		  location: nuget
2

Add a unique package name

Your package name must be unique in the NuGet repository, otherwise publishing your SDK to NuGet will fail.

generators.yml
1groups: 
2  csharp-sdk:
3	generators:
4	  - name: fernapi/fern-csharp-sdk
5		version: 2.65.0
6		output:
7		  location: nuget
8		  package-name: your-package-name
3

Configure client-class-name

The client-class-name option controls the name of the generated client. This is the name customers use to import your SDK (import { your-client-name } from 'your-package-name';).

generators.yml
1groups: 
2  csharp-sdk:
3    generators:
4      - name: fernapi/fern-csharp-sdk
5        version: 2.65.0
6        output:
7          location: nuget
8          package-name: your-package-name
9        config:
10          client_class_name: YourClientName # must be PascalCase

Generate a NuGet API key

1

Log into NuGet

Log into NuGet or create a new account.

2

Add New Key

  1. Click on your profile picture.

  2. Select API Keys, then Create.

  3. Name your key.

  4. Select Push > Push new packages and package versions as the Select Scopes type.

  5. Enter * under Select Packages > Glob Patten.

    Replacing an existing NuGet package

    If you are overriding an existing package, you can select the relevant package instead of entering *.

  6. Click Create.

Creating a New API Key
Save your new key – it won’t be displayed after you leave the page.

Configure NuGet publication

1

Add repository location

Add the path to the GitHub repository containing your C#/.NET SDK:

generators.yml
1groups: 
2  csharp-sdk:
3    generators:
4      - name: fernapi/fern-csharp-sdk
5        version: 2.65.0
6        output:
7          location: nuget
8          package-name: your-package-name
9        config:
10          client_class_name: YourClientName
11        github: 
12          repository: your-org/company-csharp
2

Configure NuGet authentication key

Add api-key: ${NUGET_API_KEY} to generators.yml to tell Fern to use the NUGET_API_KEY environment variable for authentication when publishing to the NuGet registry.

generators.yml
1groups: 
2  csharp-sdk:
3    generators:
4      - name: fernapi/fern-csharp-sdk
5        version: 2.65.0
6        output:
7          location: nuget
8          package-name: your-package-name
9          api-key: ${NUGET_API_KEY}
10        config:
11          client_class_name: YourClientName
12        github: 
13          repository: your-org/company-csharp
3

Choose your publishing mode

Optionally set the mode to control how Fern handles SDK publishing:

  • mode: release (default): Fern generates code, commits to the default branch (or the branch you specify), and tags a release automatically
  • mode: pull-request (recommended): Fern generates code and creates a PR for you to review before release
  • mode: push: Fern generates code and pushes to a branch you specify for you to review before release

You can also configure other settings, like the reviewers or license. Refer to the full github (generators.yml) reference for more information.

generators.yml
1groups: 
2  csharp-sdk:
3    generators:
4      - name: fernapi/fern-csharp-sdk
5        version: 2.65.0
6        output:
7          location: nuget
8          package-name: your-package-name
9          api-key: ${NUGET_API_KEY}
10        config:
11          client_class_name: YourClientName
12        github: 
13          repository: your-org/company-csharp
14		  mode: push
15		  branch: your-branch-name # Required for mode: push

Publish your SDK

Decide how you want to publish your SDK to NuGet. You can use GitHub workflows for automated releases or publish directly via the CLI.

Release via a GitHub workflow

Set up a release workflow via GitHub Actions so you can trigger new SDK releases directly from your source repository.

1

Set up authentication

Open your source repository in GitHub. Click on the Settings tab. Then, under the Security section, open Secrets and variables > Actions.

You can also use the url https://github.com/<your-repo>/settings/secrets/actions.

2

Add secret for your NuGet API key

  1. Select New repository secret.
  2. Name your secret NUGET_API_KEY.
  3. Add the corresponding API key you generated above.
  4. Click Add secret.
NUGET_API_KEY secret
3

Add secret for your Fern Token

  1. Select New repository secret.
  2. Name your secret FERN_TOKEN.
  3. Add your Fern token. If you don’t already have one, generate one by running fern token. By default, the fern_token is generated for the organization listed in fern.config.json.
  4. Click Add secret.
4

Set up a new workflow

Set up a CI workflow that you can manually trigger from the GitHub UI. In your repository, navigate to Actions. Select New workflow, then Set up workflow yourself. Add a workflow that’s similar to this:

.github/workflows/publish.yml
1name: Publish C#/.NET SDK
2
3on:
4  workflow_dispatch:
5    inputs:
6      version:
7        description: "The version of the C#/.NET SDK that you would like to release"
8        required: true
9        type: string
10
11jobs:
12  release:
13    runs-on: ubuntu-latest
14    steps:
15      - name: Checkout repo
16        uses: actions/checkout@v4
17
18      - name: Install Fern CLI
19        run: npm install -g fern-api
20
21      - name: Release C#/.NET SDK
22        env:
23          FERN_TOKEN: ${{ secrets.FERN_TOKEN }}
24          NUGET_API_KEY: ${{ secrets.NUGET_API_KEY }}
25        run: |
26          fern generate --group csharp-sdk --version ${{ inputs.version }} --log-level debug

You can alternatively configure your workflow to execute on: [push]. See Vapi’s npm publishing GitHub Action for an example.

5

Regenerate and release your SDK

Navigate to the Actions tab, select the workflow you just created, specify a version number, and click Run workflow. This regenerates your SDK.

Running TS publish workflow

The rest of the release process depends on your chosen mode:

  • Release mode (default): If you didn’t specify a mode or set mode: release, no further action is required. Fern automatically tags the new release with your specified version number and initiates the publishing workflow in your SDK repository.

  • Pull request or push mode: If you set mode: pull-request or mode: push, Fern creates a pull request or pushes to a branch respectively. Review and merge the PR (pull-request) or branch (push), then tag a new release to initiate the publishing workflow in your SDK repository.

Once the workflow completes, you can view your new release by logging into NuGet and navigating to Manage Packages.

Release via CLI and environment variables
1

Set npm environment variable

Set the NUGET_API_KEY environment variable on your local machine:

$export NUGET_API_KEY=your-actual-nuget-api-key
2

Regenerate and release your SDK

Regenerate your SDK, specifying the version:

$fern generate --group csharp-sdk --version <version>

The rest of the release process depends on your chosen mode:

  • Release mode (default): If you didn’t specify a mode or set mode: release, no further action is required. Fern automatically tags the new release with your specified version number and initiates the publishing workflow in your SDK repository.

  • Pull request or push mode: If you set mode: pull-request or mode: push, Fern creates a pull request or pushes to a branch respectively. Review and merge the PR (pull-request) or branch (push), then tag a new release to initiate the publishing workflow in your SDK repository.

Once the workflow completes, you can view your new release by logging into NuGet and navigating to Manage Packages.