Add Packagist Publishing Guide (#48)

Author: devalog

fern/products/sdks/overview/php/assets/packagist-package.png

@@ -3,6 +3,124 @@ title: Publishing to Packagist
 description: How to publish the Fern PHP SDK to Packagist.
 ---
 
-Learn how to publish your Fern PHP SDK to the Packagist registry. 
+Publish your public-facing Fern PHP SDK to the [Packagist
+registry](https://packagist.org/). After following the steps on this page,
+you'll have a versioned package published on Packagist.
 
-<Warning>This page is a WIP, please refer to our previous [documentation](https://buildwithfern.com/learn/sdks/guides/publish-a-public-facing-sdk).</Warning> 
+<Frame>
+	<img src="assets/packagist-package.png" alt="Versioned package published on Packagist" />
+</Frame>
+
+<Info>This guide assumes that you already have an initialized `fern` folder on your local machine. If you don’t, run `fern init`. See [PHP Quickstart](quickstart.mdx) for more details.</Info>
+
+## Set up your GitHub integration
+
+  1. Create a new GitHub repository called `company-php` (or something similar) for your SDK, if you haven't done so already.
+        <Warning>
+        Your repository must:
+        * Have **public** visibility. You can configure this in your repository's
+        **Settings**. 
+        * Have a `composer.json` file in your main branch that adheres to Packagist's
+        requirements. See Packagist's [Getting
+        Started](https://packagist.org/) and [Naming
+        Conventions](https://packagist.org/about#naming-your-package) documentation.
+        </Warning>
+  1. Install the [Fern GitHub App](https://github.com/apps/fern-api): Select **Configure**, then scroll down to **Repository Access**. Select **Only select repositories** and in the dropdown select the repository for your SDK. Click **Save**. 
+
+
+## Configure `generators.yml`
+
+<Steps>
+
+	<Step title="Run `fern add <generator>`">
+
+	  Navigate to your `generators.yml` on your local machine. Your `generators.yml` lives inside of your `fern` folder and contains all the configuration for your Fern generators. 
+
+	  Add a new generator to `generators.yml`:
+
+
+	    ```bash
+	    fern add fern-php-sdk --group php-sdk
+	    ```
+
+	  Once the command completes, you'll see a new group created in your `generators.yml`:
+
+	  ```yaml {2-8}
+      groups: 
+        php-sdk:
+          generators:
+            - name: fernapi/fern-php-sdk
+              version: <Markdown src="/snippets/version-number.mdx"/>
+	          output:
+	            location: local-file-system
+	            path: ../sdks/php
+	    ```
+
+	  </Step>
+
+
+	  <Step title="Add repository location">
+
+	  PHP publishes via Git repositories, so remove the auto-generated `output`, `location`, and `path` fields. Instead, add the path to your GitHub repository: 
+
+```yaml {6-7}
+groups: 
+  php-sdk:
+    generators:
+      - name: fernapi/fern-php-sdk
+        version: <Markdown src="/snippets/version-number.mdx"/>
+        github: 
+          repository: your-org/company-php
+```
+	  
+	  </Step>
+  </Steps>
+
+
+## Set up Packagist publishing authentication 
+
+<Steps>
+<Step title="Log into Packagist">
+
+Log into [Packagist](https://packagist.org/login/) or [create an account with Packagist](https://packagist.org/register/).
+
+</Step>
+<Step title="Submit the Repository URL">
+
+1. Click **Submit**.
+1. Input the full URL of the repository where you generated your PHP SDK, then click **Check**.
+1. Fix any errors Packagist finds in your repository, then click **Submit**. 
+
+<Frame>
+	<img src="assets/submit-package.png" alt="Submit Package Screen in Packagist" />
+</Frame>
+
+</Step>
+
+<Step title="Configure the GitHub Hook">
+
+Once you've submitted your URL, you'll be prompted to set up the GitHub Hook.
+
+  1. In to your repository, go to **Settings > Webhooks**. 
+  1. Select **"Add webhook"** 
+  1. Set the Payload URL as `https://packagist.org/api/github?username=<your.packagist.username>`
+  1. Set the content type as `application/json`
+  1. Packagist autogenerates API Tokens. To find yours, go to your **Profile**. Then, add your token to the **Secret** field. 
+  1. Set the trigger events as **Just the `push` event**
+  1. Click **"Add Webhook"**
+    <Frame>
+	<img src="assets/webhook.png" alt="GitHub Webhook for Packagist" />
+</Frame>
+</Step>
+</Steps>
+
+## Release your SDK to Packagist
+
+  At this point, you're ready to regenerate your SDK and publish it on Packagist:
+
+	```bash
+	fern generate --group php-sdk --version <version>
+	```
+    Local machine output will verify that the release is pushed to your
+    repository and tagged with the version you specified. Log back into Packagist, click on your username, and select **My packages** to see your new release. 
+