@hydration-audit/fresh

Fresh (Deno) adapter for the Hydration Cost Visibility Platform.

Analyzes hydration costs in Fresh projects by scanning the islands/ directory convention.

Installation

npm install @hydration-audit/fresh

Usage

With the CLI

# Fresh auto-detected from package.json
npx @hydration-audit/cli analyze ./dist

# Or specify explicitly
npx @hydration-audit/cli analyze --config '{"framework":"fresh"}'

Programmatic

import { analyze } from '@hydration-audit/core';
import { FreshAdapter } from '@hydration-audit/fresh';

const report = await analyze({
  adapter: new FreshAdapter(),
  cwd: '/path/to/fresh-project',
});

How It Works

Island Discovery

Fresh uses a strict convention: every file in islands/ is a hydrated component. The adapter scans this directory recursively:

islands/
  Counter.tsx      → Island "Counter"
  SearchBar.tsx    → Island "SearchBar"
  nested/
    Chart.tsx      → Island "Chart"

Page Detection

The adapter scans routes/ files for imports from islands/ to determine which pages use which islands.

Framework Detection

Fresh uses Preact by default. The adapter checks import statements — if a component imports from "react", it's marked as React; otherwise Preact.

Key Difference from Astro

Fresh islands always hydrate immediately (equivalent to client:load). There are no hydration directives like Astro's client:visible or client:idle. This means the eager-below-fold rule is especially relevant for Fresh projects.

Exported API

| Export | Description | |---|---| | FreshAdapter | FrameworkAdapter implementation | | scanIslands(srcDir) | Scan islands/ directory for components | | adapter | Pre-instantiated adapter for auto-discovery |

License

MIT