Add depiction express-middleware

README.md

@@ -3,11 +3,15 @@
 [![Pipeline](https://ci.eionet.europa.eu/buildStatus/icon?job=volto-addons%2Fvolto-addon-template%2Fmaster&subject=master)](https://ci.eionet.europa.eu/view/Github/job/volto-addons/job/volto-addon-template/job/master/display/redirect)
 [![Pipeline](https://ci.eionet.europa.eu/buildStatus/icon?job=volto-addons%2Fvolto-addon-template%2Fdevelop&subject=develop)](https://ci.eionet.europa.eu/view/Github/job/volto-addons/job/volto-addon-template/job/develop/display/redirect)
 
-[Volto](https://github.com/plone/volto) add-on
+[Volto](https://github.com/plone/volto) add-on: To use depiction image scales
 
 ## Features
 
-Demo GIF
+Make Volto aware of [depiction](https://github.com/eea/eea.depiction) image scales (e.g.: `image_preview`, `image_thumb`, `image_large`)
+
+## Usage
+
+See [volto-listing-block](https://github.com/eea/volto-listing-block)
 
 ## Getting started
 

src/index.js

@@ -1,4 +1,20 @@
+import imageMiddleware from './middleware/images';
+
 const applyConfig = (config) => {
+  // Enable Depiction
+  if (config.settings.depiction === undefined) {
+    config.settings.depiction = '/image_preview';
+  }
+
+  // Depiction express-middleware
+  if (__SERVER__) {
+    const express = require('express');
+    config.settings.expressMiddleware = [
+      ...(config.settings.expressMiddleware || []),
+      imageMiddleware(express),
+    ];
+  }
+
   return config;
 };
 

src/middleware/images.js

@@ -0,0 +1,27 @@
+import { getAPIResourceWithAuth } from '@plone/volto/helpers';
+
+const HEADERS = ['content-type', 'content-disposition', 'cache-control'];
+
+function imageMiddleware(req, res, next) {
+  const { errorHandler } = req.app.locals;
+  getAPIResourceWithAuth(req)
+    .then((resource) => {
+      // Just forward the headers that we need
+      HEADERS.forEach((header) => {
+        if (resource.headers[header]) {
+          res.set(header, resource.headers[header]);
+        }
+      });
+
+      res.send(resource.body);
+    }, errorHandler)
+    .catch(errorHandler);
+}
+
+export default function (express) {
+  const middleware = express.Router();
+
+  middleware.all(['**/image_[a-z]+$'], imageMiddleware);
+  middleware.id = 'depictionResourcesProcessor';
+  return middleware;
+}