Instruction file imported from Umeshpotha/LoanApplicationManagment-Liferay-project (.github/instructions/cx.instructions.md). Copyright stays with the author.

Liferay Client Extension Mentor Protocol (Beginner Friendly)

• Verify if the user wants a guided experience with creating a sample Client Extension. If declined, use this guide only as a reference.

Guide the user to create a form that stores data in Liferay Objects. This involves multiple client extensions in one shot:

1. Object definition (batch type) Create the initial Object definition using a batch client extension so the form has a target Object and API to call. The batch type defines the Object (e.g. custom object containing fields the form will collect).

2. Custom element (form UI) Create a custom-element client extension that renders the form and submits entries to the Object. Use the Object's REST API to create Object Entries.

ALWAYS reference the official Liferay samples as the source of truth:

• Custom element (form UI): https://github.com/liferay/liferay-portal/tree/master/workspaces/liferay-sample-workspace/client-extensions/liferay-sample-custom-element-1
• Batch (Object definition): Use Liferay docs/samples for batch client extensions that define Objects
• Key files: client-extension.yaml, assets/index.js, assets/style.css for the custom element; batch extension structure for the Object definition

Form submission and CSRF (critical for permissions)

• The form must use Liferay.Util.fetch when available so Liferay attaches session cookies and the CSRF token (p_auth) to requests. That avoids 403 when Liferay requires the token even for logged-in users.
• If Liferay.Util.fetch is not available (e.g. outside Liferay), the form falls back to native fetch.
• This is critical for permissions: without the CSRF token, users cannot submit Object Entries to the Object created by the batch extension.

Batch Object Definitions When generating *.batch-engine-data.json files, prevent these common errors:

• indexedLanguageId: Only valid for String and Clob DBTypes. Do NOT include on Date or DateTime fields or other non-text types.
• timeStorage (required for DateTime/Date fields): Liferay requires a timeStorage setting on every DateTime (or Date) object field. Always include this in objectFieldSettings for such fields, e.g. "objectFieldSettings": [ { "name": "timeStorage", "value": "convertToUTC" } ]. Use convertToUTC to store in UTC, or useInputAsFormatted to store as entered. Without it, batch import fails with this error: "The settings 'timeStorage' are required for object field [fieldName]".
• permissions: Not supported in batch imports. Set permissions via UI (Control Panel → Objects → [Object] → Permissions) after deployment.
• OAuth scopes: Include both Liferay.Headless.Batch.Engine.everything AND Liferay.Object.Admin.REST.everything in the client-extension.yaml.

Structure

• Create client-extensions/[app-name]/ for the form (custom element) and the Object definition (batch) as separate extensions.

• No build.gradle needed: The Liferay workspace plugin automatically detects client extensions in the client-extensions/ directory.

• Explain that Blade uses the Gradle Wrapper (blade gw) to package code into a .zip file and deploy it to the Liferay server

• Deploy command: blade gw deploy. Automatically copies the zip file to the Liferay server in osgi/client-extensions. Run this for the user as part of the one-shot generation.

• Verify the bundles/ folder exists. If it doesn't exist, guide users through the initial setup guide

• Verify the Liferay server is currently running at localhost:8080 so the user can test the extension

• Explain in Liferay, Client Extensions are "detached" from the core. We are building a small application that the portal will "host"

• Look for the log entry similar to STARTED [extension-id]

• Explain this log entry confirms Liferay detected your new extension and registered it in the OSGi registry

Guide the user through the Liferay UI using the following steps:

1. Open a Site Page and enter Edit Mode (Click the 'Pencil' icon)

2. Open the Fragments and Widgets sidebar (Click the '+' icon)

3. Select the Widgets tab and scroll to the Client Extensions category

4. Drag [Extension Name] onto the page layout

5. Click Publish to view the widget and interact with it

• Ask if the user wants to create another type of Client Extension
• Additional Client Extension samples and types can be found under https://github.com/liferay/liferay-portal/tree/master/workspaces/liferay-sample-workspace/client-extensions/