docs: update readme

Signed-off-by: Andrew Brandt <[email protected]>

Author: andrewb1269

README.md

@@ -1,3 +1,80 @@
-# read-all-custom-properties
+# README for the project Read All Custom Properties
 
-Github Action to read all custom properties from all repos in an organization.
+**Read all custom properties and values from all repos in the organization and write to a file.**
+
+This action uses the GitHub CLI to read all properties from all repos in the organization. It can write
+the results to a `repo-properties.yaml` file as well, for use with input to 
+[update custom properties](https://github.com/PandasWhoCode/update-custom-properties) action.
+
+---
+
+## 🚀 Getting Started
+
+1. Add this GitHub Action to your workflow.
+2. Run the workflow. A new commit will be generated on the branch you run it from containing the `repo-properties.yaml`
+file.
+
+---
+
+## Fine Grained Token Requirements
+
+To run the action within your Github CI/CD pipeline you will need to create a
+fine-grained token with the following permissions:
+
+### Organization Permissions
+
+- Read access to organization custom properties
+
+### Additional Information
+
+- [Github API for custom property for an organization](https://docs.github.com/en/rest/orgs/custom-properties?apiVersion=2022-11-28#create-or-update-a-custom-property-for-an-organization)
+- [Fine-grained personal access tokens](https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/managing-your-personal-access-tokens#creating-a-fine-grained-personal-access-token)
+- The owner of the fine-grained token must have full administrative rights to the organization.
+
+---
+
+## 📦 Inputs
+
+| Name                      | Description                                                            | Required | Default |
+|---------------------------|------------------------------------------------------------------------|-----|---------|
+| `token`                   | GitHub Personal Access Token (Fine-Grained with `Read` org scope)      | ✅ Yes | —       |
+| `overwrite-existing-file` | Boolean for choosing to overwrite `repo-properties.json`, if it exists | 🟥  No | `false` |
+| `dry-run-enabled`         | Flag to dry-run the script, will not commit in repo.                   | 🟥  No | `false` |
+| `commit-author-name`      | Author Name on the commit that will be created                         | ✅ Yes | -       |
+| `commit-author-email`     | Author Email on the commit that will be created                        | ✅ Yes | -       |
+| `commit-author-gpg-key-contents`   | GPG Key for the commit that will be created (must match the `email`)   | ✅ Yes | -       |
+| `commit-author-gpg-key-passphrase`    | GPG Key Passphrase for the key to sign the commit that will be created | ✅ Yes | -       |
+
+---
+
+## 🛠 Usage
+
+```yaml
+jobs:
+  update-schema:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: PandasWhoCode/read-all-custom-properties@1-create-an-action-to-read-all-custom-properties
+        with:
+          token: ${{ secrets.GH_CUSTOM_PROPS_TOKEN_WRITABLE }}
+          overwrite-existing-file: ${{ inputs.overwrite-existing-file }}
+          dry-run-enabled: ${{ inputs.dry-run-enabled }}
+          commit-author-name: ${{ inputs.commit-author-name }}
+          commit-author-email: ${{ inputs.commit-author-email }}
+          commit-author-gpg-key-contents: ${{ secrets.GPG_KEY_CONTENTS }}
+          commit-author-gpg-key-passphrase: ${{ secrets.GPG_KEY_PASSPHRASE }}
+```
+
+---
+
+## 👤 Author
+
+Andrew Brandt
+
+[PandasWhoCode](https://pandaswhocode.com)
+
+[[email protected]](mailto:[email protected])
+
+---