// application.js
//= require unpoly

/* application.css
 *= require unpoly
 */

Frontend assets via npm (esbuild, Webpacker, etc.)

import 'unpoly/unpoly.js'
import 'unpoly/unpoly.css'

Quick reference

Helper	Purpose
`up?`	Is this an Unpoly fragment request?
`up.target`	CSS selector being updated (success)
`up.target = 'body'`	Override the render target
`up.target?('.sel')`	Is this selector targeted?
`up.fail_target`	CSS selector targeted for failed responses
`up.fail_target?('.sel')`	Is this selector targeted on failure?
`up.any_target?('.sel')`	Is selector targeted for success or failure?
`up.validate?`	Is this a form validation request?
`up.validate_names`	Array of field names that triggered validation
`up.validate_name`	First validating field name (or `nil`)
`up.validate_name?('email')`	Is this specific field being validated?
`up.layer.mode`	Layer mode: `"root"`, `"modal"`, `"drawer"`, etc.
`up.layer.overlay?`	Is the targeted layer an overlay?
`up.layer.root?`	Is the targeted layer the root layer?
`up.layer.accept(value)`	Accept the current overlay (raises `CannotClose` on root layer)
`up.layer.dismiss(value)`	Dismiss the current overlay (raises `CannotClose` on root layer)
`up.layer.open(...)`	Request frontend to open a new overlay
`up.layer.emit(type, props)`	Emit event on the targeted layer
`up.layer.context`	Layer context hash
`up.context`	Alias for `up.layer.context`
`up.fail_layer.mode`	Mode of layer targeted for failed responses
`up.origin_layer.mode`	Mode of the layer that caused the request
`up.mode`	Shortcut for `up.layer.mode`
`up.fail_mode`	Shortcut for `up.fail_layer.mode`
`up.origin_mode`	Shortcut for `up.origin_layer.mode`
`up.emit(type, props)`	Emit event on `document` after update
`up.cache.expire`	Expire the client-side cache (triggers revalidation)
`up.cache.expire('/path/*')`	Expire matching URL pattern
`up.cache.evict`	Evict entries from the client-side cache
`up.title = 'Title'`	Set document title from server
`up.version`	Unpoly JS version string (from `X-Up-Version` header)
`up.safe_callback("js()")`	CSP-safe inline callback with nonce
`head(:no_content)`	Render empty 204 response (replaces deprecated `up.render_nothing`)
`up.no_vary { }`	Read Unpoly headers without setting Vary

Reference files

Load when the user's question covers that topic:

server-helpers.md — Full API reference: request inspection, response control, layer API, validation, events, cache control, context, CSP callbacks, failed forms, Vary headers, conditional GETs, common Rails patterns
rails-integration.md — View helper syntax (link_to, form_with, button_to, field helpers), Turbo coexistence (disabling Turbo Drive in Rails 7+), CSP setup with csp_meta_tag, global follow-all config
patterns.md — End-to-end Rails patterns: drawer overlay helper, event-driven subinteractions (up-accept-event/up-dismiss-event), create related record inline + validate parent form, authorization overlay vs root layer

unpoly-rails

Unpoly Rails

Installation

Frontend assets via Asset Pipeline