Prep

lib/create-app.js

@@ -28,6 +28,15 @@ const ResourceMapper = require('./resource-mapper')
 const aclCheck = require('@solid/acl-check')
 const { version } = require('../package.json')
 
+const { awaitSync } = require('@kaciras/deasync')
+
+const [acceptEvents, events, eventID, prep] = (awaitSync(Promise.all([
+  import('express-accept-events'),
+  import('express-events-negotiate'),
+  import('express-prep/event-id'),
+  import('express-prep')
+]))).map(lib => lib.default)
+
 const corsSettings = cors({
   methods: [
     'OPTIONS', 'HEAD', 'GET', 'PATCH', 'POST', 'PUT', 'DELETE'
@@ -61,6 +70,9 @@ function createApp (argv = {}) {
 
   const app = express()
 
+  // Add PREP support
+  app.use(acceptEvents, events, eventID, prep)
+
   initAppLocals(app, argv, ldp)
   initHeaders(app)
   initViews(app, configPath)

lib/handlers/get.js

@@ -17,6 +17,7 @@ const translate = require('../utils.js').translate
 const error = require('../http-error')
 
 const RDFs = require('../ldp').mimeTypesAsArray()
+const isRdf = require('../ldp').mimeTypeIsRdf
 
 async function handler (req, res, next) {
   const ldp = req.app.locals.ldp
@@ -110,15 +111,39 @@ async function handler (req, res, next) {
   }
 
   // If request accepts the content-type we found
+  // if (stream && negotiator.mediaType([contentType])) {
+  //   res.setHeader('Content-Type', contentType)
+  //   if (contentRange) {
+  //     const headers = { 'Content-Range': contentRange, 'Accept-Ranges': 'bytes', 'Content-Length': chunksize }
+  //     res.writeHead(206, headers)
+  //     return stream.pipe(res)
+  //   } else {
+  //     return stream.pipe(res)
+  //   }
+  // }
+
   if (stream && negotiator.mediaType([contentType])) {
-    res.setHeader('Content-Type', contentType)
+    let headers = {
+      'Content-Type': contentType
+    }
     if (contentRange) {
-      const headers = { 'Content-Range': contentRange, 'Accept-Ranges': 'bytes', 'Content-Length': chunksize }
-      res.writeHead(206, headers)
-      return stream.pipe(res)
-    } else {
-      return stream.pipe(res)
+      headers = {
+        ...headers,
+        'Content-Range': contentRange,
+        'Accept-Ranges': 'bytes',
+        'Content-Length': chunksize
+      }
+      res.statusCode = 206
     }
+
+    // PREP response
+    /* if (isRdf(contentType) && !res.sendEvents({
+      config: { prep: '' },
+      body: stream,
+      headers
+    })) return */
+    res.set(headers)
+    return stream.pipe(res)
   }
 
   // If it is not in our RDFs we can't even translate,
@@ -130,8 +155,16 @@ async function handler (req, res, next) {
     // Translate from the contentType found to the possibleRDFType desired
     const data = await translate(stream, baseUri, contentType, possibleRDFType)
     debug(req.originalUrl + ' translating ' + contentType + ' -> ' + possibleRDFType)
+    const headers = {
+      'Content-Type': possibleRDFType
+    }
+    if (isRdf(contentType) && !res.sendEvents({
+      config: { prep: '' },
+      body: data,
+      headers
+    })) return
     res.setHeader('Content-Type', possibleRDFType)
-    res.send(data)
+    res.write(data) // res.send(data)
     return next()
   } catch (err) {
     debug('error translating: ' + req.originalUrl + ' ' + contentType + ' -> ' + possibleRDFType + ' -- ' + 406 + ' ' + err.message)

lib/handlers/patch.js

@@ -11,6 +11,9 @@ const crypto = require('crypto')
 const { overQuota, getContentType } = require('../utils')
 const withLock = require('../lock')
 
+const { awaitSync } = require('@kaciras/deasync')
+const rfc822Template = awaitSync(import('express-prep/templates')).rfc822
+
 // Patch parsers by request body content type
 const PATCH_PARSERS = {
   'application/sparql-update': require('./patch/sparql-update-parser.js'),
@@ -93,6 +96,10 @@ async function patchHandler (req, res, next) {
 
     // Send the result to the client
     res.send(result)
+    // PREP response
+    res.events.prep.trigger({
+      generateNotifications: () => `\r\n${rfc822Template({ res })}`
+    })
   } catch (err) {
     return next(err)
   }