Use jimp to print hostname to photo

appetizer/.gitignore

 img/*.jpg
+node_modules/

appetizer/Dockerfile

@@ -2,6 +2,7 @@ FROM chocolateyfest/node
 WORKDIR /app
 COPY img img
 COPY package.json package.json
+RUN npm install --production
 COPY app.js app.js
 FROM chocolateyfest/node:pure
 WORKDIR /app

appetizer/app.js

@@ -2,7 +2,9 @@
 
 const fs = require('fs');
 const files = fs.readdirSync('img');
+const Jimp = require('jimp');
 const http = require('http');
+const os = require('os');
 const port = 8080;
 
 for (let i = files.length - 1; i >= 0; i--) {
@@ -13,17 +15,25 @@ const pos = Math.floor(Math.random() * files.length);
 const file = files[pos];
 
 console.log(`Got ${files.length} img files, choosing position ${pos}.`);
-http.createServer((req, res) => {
-  const path = `img/${file}`;
-  fs.readFile(path, (err, data) => {
-    if (err) {
-      res.writeHead(404, { 'Content-Type': 'text/plain' });
-      res.end(`Error handling: ${path}\n`);
-    } else {
-      res.writeHead(200, { 'Content-Type': 'image/jpeg', 'Connection': 'close' });
-      res.end(data, 'binary');
-    }
-  })
-}).listen(port);
+const path = `img/${file}`;
 
-console.log(`Listening on port ${port} serving file ${file}.`);
+Jimp.read(path).then(image => {
+  console.log('Got image');
+  Jimp.loadFont(Jimp.FONT_SANS_32_BLACK).then(black => {
+    Jimp.loadFont(Jimp.FONT_SANS_32_WHITE).then(white => {
+      console.log('Got font');
+      image
+        .scaleToFit(800, 600)
+        .print(black, 10, 10, os.hostname())
+        .print(white, 8, 8, os.hostname())
+        .quality(98) // set JPEG quality
+        .getBuffer(Jimp.MIME_JPEG, (err, data) => {
+          console.log(`Listening on port ${port} serving file ${file}.`);
+          http.createServer((req, res) => {
+            res.writeHead(200, { 'Content-Type': Jimp.MIME_JPEG, 'Connection': 'close' });
+            res.end(data, 'binary');
+          }).listen(port);        
+      });
+    });
+  });
+});

appetizer/package.json

@@ -7,5 +7,8 @@
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "author": "Stefan Scherer",
-  "license": "Apache-2.0"
+  "license": "Apache-2.0",
+  "dependencies": {
+    "jimp": "0.5.3"
+  }
 }