A minimal and scriptable way to refresh a webpage.

herl proxies requests to your website and injects a bit of javascript to allow remote page refreshes. Because it is just an HTTP proxy it is compatible with any backend language or framework.

Refreshes can be triggered with herl -n or by manually POSTing to herls notification endpoint. Of course you probably want to automate this by integrating with your editor or an external file-watcher (the example directory uses entr for generic on-save reloading).

In the below demo, because the index.html file is changed, entr calls herl -n which refreshes the browser, and go run . which restarts the application. While the application is building herl retries calling the origin server a few times until a connection can be established, so the browser only sees one refresh.

1. Start a proxy server with herl -serve -origin https://example.com.
2. Open the default proxy server url (http://127.0.0.1:3030) in the browser.
   This will show the content of example.com.
3. Run herl -notify to refresh the page from the command line.

For all flags see: herl -help.

"Hot" or "live" reloading, as seen in modern frontend frameworks, can be achieved by combining herl with, for example, entr. entr can be used to execute a command when files change, see example/makefile for a working example.

Using the Go toolchain: go install s14.nl/herl@latest

From the AUR as herl-bin, so e.g. yay -S herl-bin

The github releases page has downloads in the form of: .deb, .rpm, and .apk packages, and plain binaries.

• templ live-reload, the main inspiration for this project. Because it is built specifically for use with templ, it is hard (if not impossible) to use on its own. Its scope is also much bigger than that of herl, it also includes the functionality of entr, for example.
• node-livereload, requires changing your code, or installing a browser extension.
• browser-sync, seemingly works in a similar way to herl, but has a lot more features and complexity. Written in node js.
• entr reload-browser, doesn't seem to exist anymore, and worked by doing some x.org magic to refresh browser tabs, if I remember correctly.
• aarol/reload, requires changing your code, and is mainly intended to be used as a Go middleware.