Adding custom code (PHP) | Fern Documentation

This page covers how to add custom logic, methods, and dependencies to your PHP SDK.

Adding custom logic

To get started adding custom code:

These steps cover adding a new custom file to the SDK. To preserve line-level edits to a generated file, use Replay instead.

Create a new file and add your custom logic

src/Helper.php

1 <?php
2 
3 namespace YourNamespace;
4 
5 class Helper
6 {
7     public static function myHelper(): void
8     {
9         echo "Hello World!";
10     }
11 }

Add your file to `.fernignore`

.fernignore

1 # Specify files that shouldn't be modified by Fern
2 
3 src/Helper.php

Consume the helper

Now your users can consume the helper function by importing it from the SDK.

1 <?php
2 
3 use YourNamespace\Helper;
4 
5 Helper::myHelper();

Adding custom SDK methods

Fern also allows you to add custom methods to the SDK itself (e.g. client.my_method() ) by inheriting the Fern generated client and then extending it.

Update `generators.yml` configuration

Name your Fern-generated client something like BaseClient to reflect that this client will be extended.

generators.yml

1 - name: fern-php-sdk
2   version: 2.10.14
3   config:
4     clientName: BaseClient

Import and extend the generated client

First, import the Fern generated base client and extend it. Then, add whatever methods you want.

src/MyClient.php

1 <?php
2 
3 namespace YourNamespace;
4 
5 class MyClient extends BaseClient
6 {
7     public function myHelper(): void
8     {
9         echo "Hello World!";
10     }
11 }

Update `.fernignore`

Add the MyClient.php to .fernignore.

.fernignore

1 + src/MyClient.php

Consume the method

Instead of constructing the generated client, your users will want to construct the extended client.

1 <?php
2 
3 use YourNamespace\MyClient;
4 
5 $client = new MyClient();