1 files changed, 94 insertions, 0 deletions
diff --git a/web/renderer/index.js b/web/renderer/index.js
new file mode 100644
index 0000000..03caa1c
--- /dev/null
+++ b/web/renderer/index.js
@@ -0,0 +1,94 @@
+const http = require( 'http' );
+const fs = require( 'fs' );
+const path = require( 'path' );
+const crypto = require( 'crypto' );
+const puppeteer = require( 'puppeteer' );
+const express = require( 'express' );
+
+const PORT = 6860;
+const CACHE_DIR = path.join( __dirname, 'cache' );
+
+const host = "https://networkheaven.net";
+const app = express();
+
+if( !fs.existsSync( CACHE_DIR ) ) fs.mkdirSync( CACHE_DIR );
+
+function hash( str ) {
+  return crypto.createHash( 'sha1' ).update( str ).digest( 'hex' );
+}
+
+let browser = null;
+let cache = async ( req, res ) => {
+  const { url } = req;
+  console.log( `incoming req from ${req.headers['user-agent']} for ${url}` );
+
+  const urlObj = new URL( req.url, host );
+  const target = urlObj.href;
+
+  const key = hash( target );
+  const file = path.join( CACHE_DIR, key + '.html' );
+
+  if( fs.existsSync( file ) ) {
+    const html = fs.readFileSync( file );
+    res.writeHead( 200, { 'content-type': 'text/html' } );
+    return res.end( html );
+  }
+
+  try {
+    const page = await browser.newPage();
+
+    const r = await page.goto( target, {
+      waitUntil: 'networkidle2',
+      timeout: 30000
+    } );
+
+    const html = await page.content();
+    console.log( "caching page: " + target );
+    fs.writeFileSync( file, html );
+
+    await page.close();
+    const headers = r.headers();
+
+    res.writeHead( 200, {
+      'content-type': headers['content-type'],
+      'date': headers['date'],
+      'etag': headers['etag'],
+    } );
+    res.end( html );
+
+  } catch( e ) {
+    res.writeHead( 500, { 'content-type': 'text/plain' } );
+    res.end( 'render failed: ' + e.message );
+  }
+}
+
+app.get( "/", cache );
+app.get( /\/$/, cache );
+app.get( /#$/, cache );
+app.get( /^\/[^.]*$/, cache );
+app.use( async ( req, res ) => {
+  let url = new URL( req.url, host );
+  const r = await fetch( url.href );
+
+  if( r.ok ) {
+    const html = await r.text();
+    const headers = [];
+    for( const [k, v] of r.headers.entries() )
+      headers[k] = v;
+
+    res.writeHead( 200, {
+      'content-type': headers['content-type'],
+      'date': headers['date'],
+      'etag': headers['etag'],
+    } );
+    res.end( html );
+  }
+} );
+
+(async () => {
+  browser = await puppeteer.launch( { headless: 'new' } );
+  app.listen( PORT, async () => {
+
+    console.log( "listening on http://localhost:" + PORT );
+  } );
+})();