From 18cc671e78bcf74545535ab2ab7e4dc0ef3b6b58 Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Date: Wed, 12 Jul 2023 12:18:00 +0200
Subject: [PATCH] Make serve-analysis.js support inline serving of the HTML.

---
 server/serve-analysis.js | 61 +++++++++++++++++++++++++++++++++++++---
 1 file changed, 57 insertions(+), 4 deletions(-)

diff --git a/server/serve-analysis.js b/server/serve-analysis.js
index 4c9a24e..0008cd7 100644
--- a/server/serve-analysis.js
+++ b/server/serve-analysis.js
@@ -23,9 +23,11 @@ var json_filename = '/srv/analysis.sesse.net/www/analysis.json';
 if (process.argv.length >= 3) {
 	json_filename = process.argv[2];
 }
+var html_filename = '/srv/analysis.sesse.net/www/index.html';
 
 // Expected destination filenames.
 var serve_url = '/analysis.pl';
+var html_serve_url = '/index-inline.html';
 var hash_serve_url = '/hash';
 if (process.argv.length >= 4) {
 	serve_url = process.argv[3];
@@ -53,6 +55,7 @@ var json_lock = 0;
 
 // The current contents of the file to hand out, and its last modified time.
 var json = undefined;
+var html = undefined;
 
 // The last five timestamps, and diffs from them to the latest version.
 var historic_json = [];
@@ -192,6 +195,33 @@ var reread_file = function(event, filename) {
 	console.log("Rereading " + json_filename);
 	read_entire_file(json_filename, function(new_json_contents, mtime) {
 		replace_json(new_json_contents, mtime);
+
+		// The HTML can go async, it's not too hopeless if it's out of date by a few milliseconds
+		read_entire_file(html_filename, function(new_html_contents, html_mtime) {
+			var json_headers = {
+				'X-RGLM': mtime,
+				'X-RGNV': count_viewers(),  // May be slightly out of date.
+			};
+			if (MINIMUM_VERSION) {
+				json_headers['X-RGMV'] = MINIMUM_VERSION;
+			}
+			let inline_json = {
+				'data': JSON.parse(new_json_contents),
+				'headers': json_headers,
+			};
+			delete inline_json['data']['internal'];
+
+			new_html_contents = new_html_contents.replace(
+				'/*REPLACE:inlinejson*/',
+				'window.inline_json=' + JSON.stringify(inline_json) + ';');
+			zlib.gzip(new_html_contents, function(err, buffer) {
+				if (err) throw err;
+				html = {
+					plain: new_html_contents,
+					gzip: buffer,
+				};
+			});
+		});
 	});
 
 	if (touch_timer !== undefined) {
@@ -248,6 +278,24 @@ var send_json = function(response, ims, accept_gzip, num_viewers) {
 	}
 	response.end();
 }
+var send_html = function(response, accept_gzip, num_viewers) {
+	var headers = {
+		'Content-type': 'text/html; charset=utf-8',
+		'Vary': 'Accept-Encoding',
+	};
+
+	if (accept_gzip) {
+		headers['Content-Length'] = html.gzip.length;
+		headers['Content-Encoding'] = 'gzip';
+		response.writeHead(200, headers);
+		response.write(html.gzip);
+	} else {
+		headers['Content-Length'] = html.plain.length;
+		response.writeHead(200, headers);
+		response.write(html.plain);
+	}
+	response.end();
+}
 var mark_recently_seen = function(unique) {
 	if (unique) {
 		last_seen_clients[unique] = (new Date).getTime();
@@ -294,7 +342,7 @@ if (COUNT_FROM_VARNISH_LOG) {
 	// Note: We abuse serve_url as a regex.
 	var varnishncsa = child_process.spawn(
 		'varnishncsa', ['-F', '%{%s}t %U %q tffb=%{Varnish:time_firstbyte}x',
-		'-q', 'ReqURL ~ "^' + serve_url + '"']);
+		'-q', 'ReqURL ~ "^(' + serve_url + '|' + html_serve_url + ')"']);
 	var rl = readline.createInterface({
 		input: varnishncsa.stdout,
 		output: varnishncsa.stdin,
@@ -365,17 +413,22 @@ server.on('request', function(request, response) {
 		hash_lookup.handle_request(fen, response);
 		return;
 	}
-	if (u.pathname !== serve_url) {
+	if (u.pathname !== serve_url && u.pathname !== html_serve_url) {
 		// This is not the request you are looking for.
 		send_404(response);
 		return;
 	}
 
-	mark_recently_seen(unique);
-
 	var accept_encoding = request.headers['accept-encoding'];
 	let accept_gzip = (accept_encoding !== undefined && accept_encoding.match(/\bgzip\b/));
 
+	if (u.pathname === html_serve_url) {
+		send_html(response, accept_gzip, count_viewers());
+		return;
+	}
+
+	mark_recently_seen(unique);
+
 	// If we already have something newer than what the user has,
 	// just send it out and be done with it.
 	if (json !== undefined && (!ims || json.last_modified > ims)) {
-- 
2.39.2