hugo/livereload/livereload.go

// Copyright 2015 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Contains an embedded version of livereload.js
//
// Copyright (c) 2010-2015 Andrey Tarantsov
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

package livereload

import (
	"fmt"
	"net"
	"net/http"
	"net/url"
	"path/filepath"

	"github.com/gorilla/websocket"
)

// Prefix to signal to LiveReload that we need to navigate to another path.
const hugoNavigatePrefix = "__hugo_navigate"

var upgrader = &websocket.Upgrader{
	// Hugo may potentially spin up multiple HTTP servers, so we need to exclude the
	// port when checking the origin.
	CheckOrigin: func(r *http.Request) bool {
		origin := r.Header["Origin"]
		if len(origin) == 0 {
			return true
		}
		u, err := url.Parse(origin[0])
		if err != nil {
			return false
		}

		rHost := r.Host
		// For Github codespace in browser #9936
		if forwardedHost := r.Header.Get("X-Forwarded-Host"); forwardedHost != "" {
			rHost = forwardedHost
		}

		if u.Host == rHost {
			return true
		}

		h1, _, err := net.SplitHostPort(u.Host)
		if err != nil {
			return false
		}
		h2, _, err := net.SplitHostPort(r.Host)
		if err != nil {
			return false
		}

		return h1 == h2
	},
	ReadBufferSize: 1024, WriteBufferSize: 1024,
}

// Handler is a HandlerFunc handling the livereload
// Websocket interaction.
func Handler(w http.ResponseWriter, r *http.Request) {
	ws, err := upgrader.Upgrade(w, r, nil)
	if err != nil {
		return
	}
	c := &connection{send: make(chan []byte, 256), ws: ws}
	wsHub.register <- c
	defer func() { wsHub.unregister <- c }()
	go c.writer()
	c.reader()
}

// Initialize starts the Websocket Hub handling live reloads.
func Initialize() {
	go wsHub.run()
}

// ForceRefresh tells livereload to force a hard refresh.
func ForceRefresh() {
	RefreshPath("/x.js")
}

// NavigateToPath tells livereload to navigate to the given path.
// This translates to `window.location.href = path` in the client.
func NavigateToPath(path string) {
	RefreshPath(hugoNavigatePrefix + path)
}

// NavigateToPathForPort is similar to NavigateToPath but will also
// set window.location.port to the given port value.
func NavigateToPathForPort(path string, port int) {
	refreshPathForPort(hugoNavigatePrefix+path, port)
}

// RefreshPath tells livereload to refresh only the given path.
// If that path points to a CSS stylesheet or an image, only the changes
// will be updated in the browser, not the entire page.
func RefreshPath(s string) {
	refreshPathForPort(s, -1)
}

func refreshPathForPort(s string, port int) {
	// Tell livereload a file has changed - will force a hard refresh if not CSS or an image
	urlPath := filepath.ToSlash(s)
	portStr := ""
	if port > 0 {
		portStr = fmt.Sprintf(`, "overrideURL": %d`, port)
	}
	msg := fmt.Sprintf(`{"command":"reload","path":%q,"originalPath":"","liveCSS":true,"liveImg":true%s}`, urlPath, portStr)
	wsHub.broadcast <- []byte(msg)
}

// ServeJS serves the liverreload.js who's reference is injected into the page.
func ServeJS(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/javascript")
	w.Write(liveReloadJS())
}

func liveReloadJS() []byte {
	return []byte(livereloadJS + hugoLiveReloadPlugin)
}

var (
	// This is a patched version, see https://github.com/livereload/livereload-js/pull/84
	livereloadJS         = `!function(){return function e(t,o,n){function r(s,c){if(!o[s]){if(!t[s]){var a="function"==typeof require&&require;if(!c&&a)return a(s,!0);if(i)return i(s,!0);var l=new Error("Cannot find module '"+s+"'");throw l.code="MODULE_NOT_FOUND",l}var h=o[s]={exports:{}};t[s][0].call(h.exports,function(e){return r(t[s][1][e]||e)},h,h.exports,e,t,o,n)}return o[s].exports}for(var i="function"==typeof require&&require,s=0;s<n.length;s++)r(n[s]);return r}}()({1:[function(e,t,o){t.exports=function(e){if("function"!=typeof e)throw TypeError(e+" is not a function!");return e}},{}],2:[function(e,t,o){var n=e("./_wks")("unscopables"),r=Array.prototype;null==r[n]&&e("./_hide")(r,n,{}),t.exports=function(e){r[n][e]=!0}},{"./_hide":17,"./_wks":45}],3:[function(e,t,o){var n=e("./_is-object");t.exports=function(e){if(!n(e))throw TypeError(e+" is not an object!");return e}},{"./_is-object":21}],4:[function(e,t,o){var n=e("./_to-iobject"),r=e("./_to-length"),i=e("./_to-absolute-index");t.exports=function(e){return function(t,o,s){var c,a=n(t),l=r(a.length),h=i(s,l);if(e&&o!=o){for(;l>h;)if((c=a[h++])!=c)return!0}else for(;l>h;h++)if((e||h in a)&&a[h]===o)return e||h||0;return!e&&-1}}},{"./_to-absolute-index":38,"./_to-iobject":40,"./_to-length":41}],5:[function(e,t,o){var n={}.toString;t.exports=function(e){return n.call(e).slice(8,-1)}},{}],6:[function(e,t,o){var n=t.exports={version:"2.6.5"};"number"==typeof __e&&(__e=n)},{}],7:[function(e,t,o){var n=e("./_a-function");t.exports=function(e,t,o){if(n(e),void 0===t)return e;switch(o){case 1:return function(o){return e.call(t,o)};case 2:return function(o,n){return e.call(t,o,n)};case 3:return function(o,n,r){return e.call(t,o,n,r)}}return function(){return e.apply(t,arguments)}}},{"./_a-function":1}],8:[function(e,t,o){t.exports=function(e){if(null==e)throw TypeError("Can't call method on  "+e);return e}},{}],9:[function(e,t,o){t.exports=!e("./_fails")(function(){return 7!=Object.defineProperty({},"a",{get:function(){return 7}}).a})},{"./_fails":13}],10:[function(e,t,o){var n=e("./_is-object"),r=e("./_global").document,i=n(r)&&n(r.createElement);t.exports=function(e){return i?r.createElement(e):{}}},{"./_global":15,"./_is-object":21}],11:[function(e,t,o){t.exports="constructor,hasOwnProperty,isPrototypeOf,propertyIsEnumerable,toLocaleString,toString,valueOf".split(",")},{}],12:[function(e,t,o){var n=e("./_global"),r=e("./_core"),i=e("./_hide"),s=e("./_redefine"),c=e("./_ctx"),a=function(e,t,o){var l,h,u,d,f=e&a.F,p=e&a.G,_=e&a.S,m=e&a.P,g=e&a.B,y=p?n:_?n[t]||(n[t]={}):(n[t]||{}).prototype,v=p?r:r[t]||(r[t]={}),w=v.prototype||(v.prototype={});for(l in p&&(o=t),o)u=((h=!f&&y&&void 0!==y[l])?y:o)[l],d=g&&h?c(u,n):m&&"function"==typeof u?c(Function.call,u):u,y&&s(y,l,u,e&a.U),v[l]!=u&&i(v,l,d),m&&w[l]!=u&&(w[l]=u)};n.core=r,a.F=1,a.G=2,a.S=4,a.P=8,a.B=16,a.W=32,a.U=64,a.R=128,t.exports=a},{"./_core":6,"./_ctx":7,"./_global":15,"./_hide":17,"./_redefine":34}],13:[function(e,t,o){t.exports=function(e){try{return!!e()}catch(e){return!0}}},{}],14:[function(e,t,o){t.exports=e("./_shared")("native-function-to-string",Function.toString)},{"./_shared":37}],15:[function(e,t,o){var n=t.exports="undefined"!=typeof window&&window.Math==Math?window:"undefined"!=typeof self&&self.Math==Math?self:Function("return this")();"number"==typeof __g&&(__g=n)},{}],16:[function(e,t,o){var n={}.hasOwnProperty;t.exports=function(e,t){return n.call(e,t)}},{}],17:[function(e,t,o){var n=e("./_object-dp"),r=e("./_property-desc");t.exports=e("./_descriptors")?function(e,t,o){return n.f(e,t,r(1,o))}:function(e,t,o){return e[t]=o,e}},{"./_descriptors":9,"./_object-dp":28,"./_property-desc":33}],18:[function(e,t,o){var n=e("./_global").document;t.exports=n&&n.documentElement},{"./_global":15}],19:[function(e,t,o){t.exports=!e("./_descriptors")&&!e("./_fails")(function(){return 7!=Object.defineProperty(e("./_dom-create")("div"),"a",{get:function(){return 7}}).a})},{"./_descriptors":9,"./_dom-create":10,"./_fails":13}],20:[function(e,t,o){var n=e("./_cof");t.exports=Object("z").propertyIsEnumerable(0)?Object:f
	hugoLiveReloadPlugin = fmt.Sprintf(`
/*
Hugo adds a specific prefix, "__hugo_navigate", to the path in certain situations to signal
navigation to another content page.
*/

function HugoReload() {}

HugoReload.identifier = 'hugoReloader';
HugoReload.version = '0.9';

HugoReload.prototype.reload = function(path, options) {
	var prefix = %q;

	if (path.lastIndexOf(prefix, 0) !== 0) {
		return false
	}
	
	path = path.substring(prefix.length);

	var portChanged = options.overrideURL && options.overrideURL != window.location.port
	
	if (!portChanged && window.location.pathname === path) {
		window.location.reload();
	} else {
		if (portChanged) {
			window.location = location.protocol + "//" + location.hostname + ":" + options.overrideURL + path;
		} else {
			window.location.pathname = path;
		}
	}

	return true;
};

LiveReload.addPlugin(HugoReload)
`, hugoNavigatePrefix)
)