keep browser connection alive

src/app.js

@@ -13,13 +13,16 @@ const requestLogger = require('koa-logger');
 const validate = require('koa-validate');
 const mount = require('koa-mount');
 
-const pdf = require('./pdf');
-const printer = require('./printer');
+
+// const pdf = require('./pdf');
+// const Printer = require('pagedjs-cli');
+
+const printerRoute = require('./printer');
 
 const app = new Koa();
 const router = new Router();
 
-router.post('/', printer);
+router.post('/', printerRoute);
 
 app.use(cors());
 
@@ -36,16 +39,22 @@ app.use(bodyParser(
 
 validate(app);
 
-
-// app.use(ctx => {
-//   console.log(ctx.request.body);
+// app.use((ctx, next) => {
+//   ctx.printer = printer;
+//   next();
 // });
 
-
 app.use(router.routes())
 
-app.listen(PORT, () => {
+let server = app.listen(PORT, () => {
   console.warn(`Printer server listening on ${PORT}, in ${process.env.NODE_ENV} mode`);
 });
 
+process.on('SIGTERM', () => {
+  console.log('Closing http server.');
+  printer.close();
+  server.close();
+});
+
+
 module.exports = app;

src/printer.js

 const fs = require('fs');
 const Printer = require('pagedjs-cli');
 
+const printer = new Printer();
+printer.setup();
+
+printer.on("page", (page) => {
+  console.debug("Rendering: Page " + (page.position + 1))
+});
+
+printer.on("rendered", (msg) => {
+  console.debug("Generating");
+});
+
+printer.on("postprocessing", (msg) => {
+  console.debug("Processing");
+});
+
 module.exports = async (ctx) => {
   ctx.type = 'application/pdf';
   ctx.attachment('out.pdf');
 
   const { url, html, options, headers } = ctx.request.body;
 
-  // console.debug('URL: ', url);
-  // console.debug('HTML: ', html);
+  console.debug('URL: ', url);
+  console.debug('HTML: ', html && html.length);
   // console.debug('OPTIONS: ', options);
   // console.debug('HEADERS: ', headers);
 
-  let printer = new Printer();
-
-  printer.on("page", (page) => {
-    console.debug("Rendering: Page " + (page.position + 1))
-  });
-
-  printer.on("rendered", (msg) => {
-    console.debug("Generating");
-  });
-
-  printer.on("postprocessing", (msg) => {
-    console.debug("Processing");
-  });
-
   let file;
 
   if (url) {