...

_packages/media-server/srv/media-service.cds

@@ -0,0 +1,8 @@
+using { sap.capire.media as db } from '../db/data-model';
+namespace sap.capire.media;
+
+service MediaServer  {
+    entity Media   as projection on db.Media ;
+}
+
+ 

_packages/media-server/srv/media-service.js

@@ -0,0 +1,68 @@
+const loki = require('lokijs')
+const db = new loki('DB')
+const mediaDB = db.addCollection('Media')
+const { Readable, PassThrough } = require('stream')
+
+module.exports = srv => {
+  srv.before('CREATE', 'Media', req => {
+    const obj = mediaDB.insert({ media: '' })
+    req.data.id = obj.$loki
+  })
+
+  srv.on('UPDATE', 'Media', (req, next) => {
+    const url = req._.req.path
+    if (url.includes('content')) {
+      const id = req.data.id
+      const obj = mediaDB.get(id)
+      if (!obj) {
+        req.reject(404, 'No record found for the ID')
+        return
+      }
+      const stream = new PassThrough()
+      const chunks = []
+      stream.on('data', chunk => {
+        chunks.push(chunk)
+      })
+      stream.on('end', () => {
+        obj.media = Buffer.concat(chunks).toString('base64')
+        mediaDB.update(obj)
+      })
+      req.data.content.pipe(stream)
+    } else return next()
+  })
+
+  srv.on('READ', 'Media', (req, next) => {
+    const url = req._.req.path
+    if (url.includes('content')) {
+      const id = req.data.id
+      const mediaObj = mediaDB.get(id)
+      if (!mediaObj) {
+        req.reject(404, 'Media not found for the ID')
+        return
+      }
+      const decodedMedia = new Buffer(
+        mediaObj.media.split(';base64,').pop(),
+        'base64'
+      )
+      return _formatResult(decodedMedia)
+    } else return next() //> delegate to next/default handlers
+  })
+
+  srv.on('DELETE', 'Media', (req, next) => {
+    const id = req.data.id
+    mediaDB
+      .chain()
+      .find({ $loki: id })
+      .remove()
+    return next() //> delegate to next/default handlers
+  })
+
+  function _formatResult (decodedMedia) {
+    const readable = new Readable()
+    const result = new Array()
+    readable.push(decodedMedia)
+    readable.push(null)
+    result.push({ value: readable })
+    return result
+  }
+}