Object Preview service

2021-04-29 15:11:22 +03:00
parent fb96e49852
commit 93edc65f66
30 changed files with 18312 additions and 5 deletions
@@ -27,13 +27,13 @@ workflows:
              only: /^v.*/
            branches:
              ignore: /.*/
-  test-test:
+  cristi-ci-test:
    jobs:
      - docker_build_and_deploy:
          context: main-builds
          filters:
            branches:
-              only: cristi/ci-test-deployment
+              only: cristi/ci-test

 jobs:
  test_server:
@@ -86,7 +86,10 @@ jobs:
          name: Build Server
          command: env SPECKLE_SERVER_PACKAGE=server ./.circleci/build.sh
      - run:
-          name: Deploy Frontend and Server
+          name: Build Object Preview Service
+          command: env SPECKLE_SERVER_PACKAGE=preview-service ./.circleci/build.sh
+      - run:
+          name: Deploy
          command: ./.circleci/deploy.sh
      - run:
          name: Test deployment
@@ -28,6 +28,13 @@ echo "$K8S_CLUSTER_CERTIFICATE" | base64 --decode > k8s_cert.crt
  --token=$K8S_TOKEN \
  set image deployment/$TARGET_SPECKLE_DEPLOYMENT-server main=$DOCKER_IMAGE_TAG-server:$IMAGE_VERSION_TAG

+./kubectl \
+  --kubeconfig=/dev/null \
+  --server=$K8S_SERVER \
+  --certificate-authority=k8s_cert.crt \
+  --token=$K8S_TOKEN \
+  set image deployment/$TARGET_SPECKLE_DEPLOYMENT-preview-service main=$DOCKER_IMAGE_TAG-preview-service:$IMAGE_VERSION_TAG
+

 # Wait for rollout to complete
 ./kubectl \
@@ -43,3 +50,10 @@ echo "$K8S_CLUSTER_CERTIFICATE" | base64 --decode > k8s_cert.crt
  --certificate-authority=k8s_cert.crt \
  --token=$K8S_TOKEN \
  rollout status -w deployment/$TARGET_SPECKLE_DEPLOYMENT-server --timeout=1m
+
+./kubectl \
+  --kubeconfig=/dev/null \
+  --server=$K8S_SERVER \
+  --certificate-authority=k8s_cert.crt \
+  --token=$K8S_TOKEN \
+  rollout status -w deployment/$TARGET_SPECKLE_DEPLOYMENT-preview-service --timeout=1m
@@ -0,0 +1,41 @@
+{
+  "env": {
+    "browser": true,
+    "commonjs": true,
+    "es2020": true
+  },
+  "parserOptions": {
+    "ecmaVersion": 11
+  },
+  "ignorePatterns": ["node_modules/*"],
+  "rules": {
+    "arrow-spacing": [
+      2,
+      {
+        "before": true,
+        "after": true
+      }
+    ],
+    "array-bracket-spacing": [2, "always"],
+    "object-curly-spacing": [1, "always"],
+    "block-spacing": [2, "always"],
+    "camelcase": [
+      1,
+      {
+        "properties": "always"
+      }
+    ],
+    "space-in-parens": [2, "always"],
+    "keyword-spacing": 2,
+    "semi": [1, "never"],
+    "quotes": [1, "single"],
+    "indent": ["error", 2],
+    "space-unary-ops": [
+      2,
+      {
+        "words": true,
+        "nonwords": false
+      }
+    ]
+  }
+}
@@ -0,0 +1,44 @@
+# NOTE: Docker context should be set to git root directory, to include the viewer
+
+FROM node:14.16.0-buster-slim as node
+
+RUN apt-get update && apt-get install -y \
+  tini \
+  && rm -rf /var/lib/apt/lists/*
+
+# chromium dependencies
+RUN apt-get update && apt-get install -y \
+  ca-certificates fonts-liberation libappindicator3-1 libasound2 libatk-bridge2.0-0 libatk1.0-0 libc6 libcairo2 libcups2 libdbus-1-3 libexpat1 libfontconfig1 libgbm1 libgcc1 libglib2.0-0 libgtk-3-0 libnspr4 libnss3 libpango-1.0-0 libpangocairo-1.0-0 libstdc++6 libx11-6 libx11-xcb1 libxcb1 libxcomposite1 libxcursor1 libxdamage1 libxext6 libxfixes3 libxi6 libxrandr2 libxrender1 libxss1 libxtst6 lsb-release wget xdg-utils \
+  && rm -rf /var/lib/apt/lists/*
+
+
+ARG NODE_ENV=production
+ENV NODE_ENV=${NODE_ENV}
+WORKDIR /app
+
+
+WORKDIR /opt/objectloader
+COPY packages/objectloader/package*.json ./
+RUN npm install --production=false
+COPY packages/objectloader .
+# RUN npm run build
+
+WORKDIR /opt/viewer
+COPY packages/viewer/package*.json ./
+RUN npm install ../objectloader
+# Install dependencies and devDependencies
+RUN npm install --production=false
+COPY packages/viewer .
+RUN npm run build
+
+WORKDIR /opt/preview-service
+COPY packages/preview-service/package*.json ./
+RUN npm install ../objectloader
+RUN npm install ../viewer
+RUN npm ci --production=false
+COPY packages/preview-service .
+RUN npm run build-fe
+
+
+ENTRYPOINT [ "tini", "--" ]
+CMD ["node", "bin/www"]
@@ -0,0 +1,40 @@
+'use strict'
+
+var createError = require( 'http-errors' )
+var express = require( 'express' )
+var path = require( 'path' )
+var cookieParser = require( 'cookie-parser' )
+var logger = require( 'morgan' )
+
+var indexRouter = require( './routes/index' )
+var previewRouter = require( './routes/preview' )
+var objectsRouter = require( './routes/objects' )
+
+var app = express()
+
+app.use( logger( 'dev' ) )
+app.use( express.json() )
+app.use( express.urlencoded( { extended: false } ) )
+app.use( cookieParser() )
+app.use( express.static( path.join( __dirname, 'public' ) ) )
+
+app.use( '/', indexRouter )
+app.use( '/preview', previewRouter )
+app.use( '/objects', objectsRouter )
+
+// catch 404 and forward to error handler
+app.use( function( req, res, next ) {
+  next( createError( 404 ) )
+} )
+
+// error handler
+app.use( function( err, req, res, next ) {
+  let errorText = err.message
+  if ( req.app.get( 'env' ) === 'development' ) {
+    errorText = `<html><body><pre>${err.message}: ${err.status}\n${err.stack}</pre></body></html>`
+  }
+  res.status( err.status || 500 )
+  res.send( errorText )
+} )
+
+module.exports = app
@@ -0,0 +1,86 @@
+'use strict'
+
+const crypto = require( 'crypto' )
+const knex = require( '../knex' )
+const fetch = require( 'node-fetch' )
+const ObjectPreview = ( ) => knex( 'object_preview' )
+const Previews = ( ) => knex( 'previews' )
+
+async function startTask() {
+  let { rows } = await knex.raw( `
+    UPDATE object_preview
+    SET 
+      "previewStatus" = 1,
+      "lastUpdate" = NOW()
+    FROM (
+      SELECT "streamId", "objectId" FROM object_preview
+      WHERE "previewStatus" = 0 OR ("previewStatus" = 1 AND "lastUpdate" < NOW() - INTERVAL '1 HOUR')
+      ORDER BY "priority" ASC, "lastUpdate" ASC
+      LIMIT 1
+    ) as task
+    WHERE object_preview."streamId" = task."streamId" AND object_preview."objectId" = task."objectId"
+    RETURNING object_preview."streamId", object_preview."objectId"
+  ` )
+  return rows[0]
+}
+
+async function doTask( task ) {
+  
+  let previewUrl = `http://127.0.0.1:3001/preview/${task.streamId}/${task.objectId}`
+  let res = await fetch( previewUrl )
+  res = await res.json()
+  // let imgBuffer = await res.buffer()  // this gets the binary response body
+
+  let metadata = {}
+
+  for ( let angle in res ) {
+    const imgBuffer = new Buffer.from( res[angle].replace( /^data:image\/\w+;base64,/, '' ), 'base64' )
+    let previewId = crypto.createHash( 'md5' ).update( imgBuffer ).digest( 'hex' )
+
+    // Save preview image
+    let insertionObject = { id: previewId, data: imgBuffer }
+    //await Previews().insert( insertionObject )
+    //let dbQuery = Previews().insert( insertionObject ).toString( ) + ' on conflict do nothing'
+    await knex.raw( 'INSERT INTO "previews" (id, data) VALUES (?, ?) ON CONFLICT DO NOTHING', [ previewId, imgBuffer ] )
+
+    metadata[angle] = previewId
+  }
+
+  // Update preview metadata
+  await knex.raw( `
+    UPDATE object_preview
+    SET
+      "previewStatus" = 2,
+      "lastUpdate" = NOW(),
+      "preview" = ?
+    WHERE "streamId" = ? AND "objectId" = ?
+  `, [ metadata, task.streamId, task.objectId ] )
+
+
+}
+
+async function tick() {
+  try {
+    let task = await startTask()
+    if ( !task ) {
+      setTimeout( tick, 1000 )
+      return
+    }
+
+    doTask( task )
+
+    // Check for another task very soon
+    setTimeout( tick, 10 )
+  } catch ( err ) {
+    console.log( 'Error executing task: ', err )
+    setTimeout( tick, 5000 )
+  }
+}
+
+async function startPreviewService() {
+  console.log( '📸 Started Preview Service' )
+
+  tick()
+}
+
+module.exports = { startPreviewService }
@@ -0,0 +1,94 @@
+#!/usr/bin/env node
+
+/**
+ * Module dependencies.
+ */
+
+var app = require( '../app' )
+var debug = require( 'debug' )( 'preview-service:server' )
+var http = require( 'http' )
+var { startPreviewService } = require( '../bg_service' )
+
+/**
+ * Get port from environment and store in Express.
+ */
+
+var port = normalizePort( process.env.PORT || '3001' )
+app.set( 'port', port )
+
+/**
+ * Create HTTP server.
+ */
+
+var server = http.createServer( app )
+
+/**
+ * Listen on provided port, on all network interfaces.
+ */
+
+server.listen( port, '127.0.0.1' )
+server.on( 'error', onError )
+server.on( 'listening', onListening )
+
+/**
+ * Normalize a port into a number, string, or false.
+ */
+
+function normalizePort( val ) {
+  var port = parseInt( val, 10 )
+
+  if ( isNaN( port ) ) {
+    // named pipe
+    return val
+  }
+
+  if ( port >= 0 ) {
+    // port number
+    return port
+  }
+
+  return false
+}
+
+/**
+ * Event listener for HTTP server "error" event.
+ */
+
+function onError( error ) {
+  if ( error.syscall !== 'listen' ) {
+    throw error
+  }
+
+  var bind = typeof port === 'string'
+    ? 'Pipe ' + port
+    : 'Port ' + port
+
+  // handle specific listen errors with friendly messages
+  switch ( error.code ) {
+  case 'EACCES':
+    console.error( bind + ' requires elevated privileges' )
+    process.exit( 1 )
+    break
+  case 'EADDRINUSE':
+    console.error( bind + ' is already in use' )
+    process.exit( 1 )
+    break
+  default:
+    throw error
+  }
+}
+
+/**
+ * Event listener for HTTP server "listening" event.
+ */
+
+function onListening() {
+  var addr = server.address()
+  var bind = typeof addr === 'string'
+    ? 'pipe ' + addr
+    : 'port ' + addr.port
+  debug( 'Listening on ' + bind )
+
+
+  startPreviewService()
+}
@@ -0,0 +1,8 @@
+'use strict'
+
+module.exports = require( 'knex' )( {
+  client: 'pg',
+  connection: process.env.PG_CONNECTION_STRING || 'postgres://speckle:speckle@localhost/speckle',
+  pool: { min: 1, max: 1 }
+  // migrations are in managed in the server package
+} )
@@ -0,0 +1,44 @@
+{
+  "name": "@speckle/preview-service",
+  "version": "2.0.0",
+  "description": "Generate PNG previews of Speckle objects by using a headless viewer",
+  "main": "index.js",
+  "homepage": "https://speckle.systems",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/specklesystems/speckle-server.git",
+    "directory": "packages/preview-service"
+  },
+  "scripts": {
+    "dev": "DEBUG='preview-service:*' nodemon ./bin/www",
+    "build-fe": "webpack --env dev --config webpack.config.render_page.js && webpack --env build --config webpack.config.render_page.js"
+  },
+  "dependencies": {
+    "@speckle/objectloader": "file:../objectloader",
+    "@speckle/viewer": "file:../viewer",
+    "cookie-parser": "~1.4.4",
+    "crypto": "^1.0.1",
+    "debug": "~2.6.9",
+    "express": "~4.16.1",
+    "file-type": "^16.3.0",
+    "http-errors": "~1.6.3",
+    "jade": "~1.11.0",
+    "knex": "^0.95.4",
+    "morgan": "~1.9.1",
+    "node-fetch": "^2.6.1",
+    "pg": "^8.6.0",
+    "pg-query-stream": "^4.1.0",
+    "puppeteer": "^9.0.0",
+    "zlib": "^1.0.5"
+  },
+  "devDependencies": {
+    "@babel/core": "^7.13.16",
+    "babel-loader": "^8.2.2",
+    "clean-webpack-plugin": "^4.0.0-alpha.0",
+    "html-webpack-plugin": "^5.3.1",
+    "nodemon": "^2.0.7",
+    "webpack": "^5.35.0",
+    "webpack-cli": "^4.6.0",
+    "webpack-dev-server": "^3.11.2"
+  }
+}
@@ -0,0 +1 @@
+Speckle Object Preview Service
@@ -0,0 +1,12 @@
+<!doctype html><html><head><meta charset="utf-8"/><title>Speckle Viewer</title><meta name="viewport" content="width=device-width,initial-scale=1"><style>body{
+        font-family: 'Space Mono', monospace !important;
+        margin: 0px;
+      }
+      button {
+        font-family: 'Space Mono', monospace !important;
+        border-color: #0A66FF;
+      }
+      #renderer{
+        height: 400px;
+        width: 700px;
+      }</style><script defer="defer" src="viewer.min.js"></script></head><body><div id="renderer"></div></body></html>
@@ -0,0 +1 @@
+/*! For license information please see Speckle.js.LICENSE.txt */
@@ -0,0 +1,19 @@
+
+import { Viewer, Converter } from '@speckle/viewer'
+import ObjectLoader from '@speckle/objectloader'
+
+let v = new Viewer( { container: document.getElementById( 'renderer' ), showStats: false } )
+// v.on( 'load-progress', args => console.log( args ) )
+
+window.v = v
+
+window.LoadData = async function LoadData( url ) {
+  await v.loadObject( url, token )
+}
+
+window.onload = (event) => {
+  let testUrl = window.location.hash.substr(1);
+  if (testUrl) {
+    LoadData(testUrl);
+  };
+};
@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+ <html>
+   <head>
+     <meta charset="utf-8" />
+     <title>Speckle Viewer</title>
+     <meta name="viewport" content="width=device-width, initial-scale=1">
+<!--
+     <link rel="preconnect" href="https://fonts.gstatic.com">
+      <link href="https://fonts.googleapis.com/css2?family=Space+Mono:ital,wght@0,400;0,700;1,700&display=swap" rel="stylesheet">
+     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/skeleton/2.0.4/skeleton.min.css" integrity="sha512-EZLkOqwILORob+p0BXZc+Vm3RgJBOe1Iq/0fiI7r/wJgzOFZMlsqTa29UEl6v6U6gsV4uIpsNZoV32YZqrCRCQ==" crossorigin="anonymous" />
+-->
+     <style type="text/css">
+      body{
+        font-family: 'Space Mono', monospace !important;
+        margin: 0px;
+      }
+      button {
+        font-family: 'Space Mono', monospace !important;
+        border-color: #0A66FF;
+      }
+      #renderer{
+        height: 400px;
+        width: 700px;
+      }
+    </style>
+   </head>
+   <body>
+    <div id="renderer"></div>
+   </body>
+ </html>
@@ -0,0 +1,10 @@
+'use strict'
+
+var express = require( 'express' )
+var router = express.Router()
+
+router.get( '/', function( req, res, next ) {
+  res.send( 'Speckle Object Preview Service' )
+} )
+
+module.exports = router
@@ -0,0 +1,103 @@
+'use strict'
+
+const zlib = require( 'zlib' )
+var express = require( 'express' )
+var { getObject, getObjectChildrenStream } = require( './services/objects_utils' )
+
+var router = express.Router()
+
+
+// This method was copy-pasted from the server method, without authentication/authorization (this web service is an internal one)
+router.get( '/:streamId/:objectId', async function( req, res, next ) {
+
+  // Populate first object (the "commit")
+  let obj = await getObject( { streamId: req.params.streamId, objectId: req.params.objectId } )
+
+  if ( !obj ) {
+    return res.status( 404 ).send( `Failed to find object ${req.params.objectId}.` )
+  }
+
+  obj = obj.data
+
+  let simpleText = req.headers.accept === 'text/plain'
+
+  let dbStream = await getObjectChildrenStream( { streamId: req.params.streamId, objectId: req.params.objectId } )
+
+  let currentChunkSize = 0
+  let maxChunkSize = 50000
+  let chunk = simpleText ? '' : [ ]
+  let isFirst = true
+
+  res.writeHead( 200, { 'Content-Encoding': 'gzip', 'Content-Type': simpleText ? 'text/plain' : 'application/json' } )
+
+  const gzip = zlib.createGzip( )
+
+  if ( !simpleText ) gzip.write( '[' )
+
+  // helper func to flush the gzip buffer
+  const writeBuffer = ( addTrailingComma ) => {
+    // console.log( `writing buff ${currentChunkSize}` )
+    if ( simpleText ) {
+      gzip.write( chunk )
+    } else {
+      gzip.write( chunk.join( ',' ) )
+      if ( addTrailingComma ) {
+        gzip.write( ',' )
+      }
+    }
+    gzip.flush( )
+    chunk = simpleText ? '' : [ ]
+  }
+
+  var objString = JSON.stringify( obj )
+  if ( simpleText ) {
+    chunk += `${obj.id}\t${objString}\n`
+  } else {
+    chunk.push( objString )
+  }
+  writeBuffer( true )
+
+  let k = 0
+  let requestDropped = false
+  dbStream.on( 'data', row => {
+    try {
+      let data = JSON.stringify( row.data )
+      currentChunkSize += Buffer.byteLength( data, 'utf8' )
+      if ( simpleText ) {
+        chunk += `${row.data.id}\t${data}\n`
+      } else {
+        chunk.push( data )
+      }
+      if ( currentChunkSize >= maxChunkSize ) {
+        currentChunkSize = 0
+        writeBuffer( true )
+      }
+      k++
+    } catch ( e ) {
+      requestDropped = true
+      debug( 'speckle:error' )( `'Failed to find object, or object is corrupted.' ${req.params.objectId}` )
+      return
+    }
+  } )
+
+  dbStream.on( 'error', err => {
+    console.log("DB ERROR ",err)
+    debug( 'speckle:error' )( `Error in streaming object children for ${req.params.objectId}: ${err}` )
+    requestDropped = true
+    return
+  } )
+
+  dbStream.on( 'end', ( ) => {
+    if ( currentChunkSize !== 0 ) {
+      writeBuffer( false )
+      if ( !simpleText ) gzip.write( ']' )
+    }
+    gzip.end( )
+  } )
+
+  // 🚬
+  gzip.pipe( res )
+
+} )
+
+module.exports = router
@@ -0,0 +1,113 @@
+'use strict'
+
+var express = require( 'express' )
+var router = express.Router()
+const puppeteer = require( 'puppeteer' )
+
+function sleep( ms ) {
+  return new Promise( ( resolve ) => {
+    setTimeout( resolve, ms )
+  } )
+}
+
+async function getScreenshot( objectUrl ) {
+  const browser = await puppeteer.launch( { args: [ '--no-sandbox', '--disable-setuid-sandbox' ] } )
+  const page = await browser.newPage()
+  await page.goto( 'http://127.0.0.1:3001/render/' )
+
+  console.log("Page loaded")
+
+  console.time( 'lo' )
+  const scr = await page.evaluate( async ( objectUrl ) => {
+    waitForAnimation = async ( ms=70 ) => await new Promise( ( resolve ) => {
+      setTimeout( resolve, ms )
+    } )
+    let scr = {}
+    let stepAngle = 0.261799
+    v.postprocessing = false
+    v.sceneManager.skipPostLoad = true
+    await v.loadObject( objectUrl, '' )
+    v.interactions.zoomExtents( 0.95, false )
+    await waitForAnimation()
+    scr['0'] = v.interactions.screenshot()
+
+    for ( let i = 1; i < 3; i++ ) {
+      v.interactions.rotateCamera( stepAngle, undefined, false )
+      await waitForAnimation()
+      scr[( -1 * i ) + ''] = v.interactions.screenshot()
+    }
+    v.interactions.rotateCamera( -2 * stepAngle, undefined, false )
+    await waitForAnimation()
+    for ( let i = 1; i < 3; i++ ) {
+      v.interactions.rotateCamera( -1 * stepAngle, undefined, false )
+      await waitForAnimation()
+      scr[i + ''] = v.interactions.screenshot()
+    }
+    /*
+    v.interactions.rotateCamera( 2 * stepAngle, transition=false )
+    await waitForAnimation( 500 )
+
+    let dirArray = [ 'top', 'bottom', 'front', 'back', 'left', 'right' ]
+    for ( let i in dirArray ) {
+      let d = dirArray[i]
+      v.interactions.rotateTo( d )
+      await waitForAnimation()
+      scr[d] = v.interactions.screenshot()
+    }
+    */
+    return scr
+  }, objectUrl )
+
+  
+  return scr
+
+  return `
+  <html><body>
+  <img height="200px" src="${scr['-2']}" /><br />
+  <img height="200px" src="${scr['-1']}" /><br />
+  <img height="200px" src="${scr['0']}" /><br />
+  <img height="200px" src="${scr['1']}" /><br />
+  <img height="200px" src="${scr['2']}" /><br />
+  </body></html>
+  `
+
+  const imageBuffer = new Buffer.from( b64Image.replace( /^data:image\/\w+;base64,/, '' ), 'base64' )
+
+  console.timeEnd( 'lo' )
+
+  // await page.waitForTimeout(500);
+  //var response = await page.screenshot({
+  //  type: 'png',
+  //  clip: {x: 0, y: 0, width: 800, height: 800}
+  //});
+
+  // Don't await for cleanup
+  browser.close()
+
+  return imageBuffer
+};
+
+
+router.get( '/:streamId/:objectId', async function( req, res, next ) {
+  let objectUrl = `http://127.0.0.1:3001/streams/${req.params.streamId}/objects/${req.params.objectId}`
+  /*
+  let authToken = ''
+  let authorizationHeader = req.header( 'Authorization' )
+  if ( authorizationHeader && authorizationHeader.toLowerCase().startsWith( 'bearer ' ) ) {
+    authToken = authorizationHeader.Substring( 'Bearer '.Length ).Trim()
+  }
+  // useful for testing (not the recommended way of passing the auth token)
+  if ( req.query.authToken ) {
+    authToken = req.query.authToken
+  }
+  */
+
+  console.log( objectUrl )
+  console.time( 'test' )
+  let scr = await getScreenshot( objectUrl )
+  console.timeEnd( 'test' )
+  // res.setHeader( 'content-type', 'image/png' )
+  res.send( scr )
+} )
+
+module.exports = router
@@ -0,0 +1,32 @@
+'use strict'
+
+let debug = require( 'debug' )( 'speckle:services' )
+const knex = require( '../../knex' )
+
+const Objects = ( ) => knex( 'objects' )
+const Closures = ( ) => knex( 'object_children_closure' )
+
+module.exports = {
+
+  async getObject( { streamId, objectId } ) {
+    let res = await Objects( ).where( { streamId: streamId, id: objectId } ).select( '*' ).first( )
+    if ( !res ) return null
+    res.data.totalChildrenCount = res.totalChildrenCount
+    delete res.streamId
+    return res
+  },
+
+  async getObjectChildrenStream( { streamId, objectId } ) {
+    let q = Closures( )
+    q.select( 'id' )
+    q.select( 'data' )
+    q.rightJoin( 'objects', function() {
+      this.on( 'objects.streamId', '=', 'object_children_closure.streamId' )
+        .andOn( 'objects.id', '=', 'object_children_closure.child' )
+    } )
+      .where( knex.raw( 'object_children_closure."streamId" = ? AND parent = ?', [ streamId, objectId ] ) )
+      .orderBy( 'objects.id' )
+    return q.stream( )
+  }
+
+}
@@ -0,0 +1,57 @@
+/* global __dirname, require, module*/
+const HtmlWebpackPlugin = require( 'html-webpack-plugin' )
+const { CleanWebpackPlugin } = require( 'clean-webpack-plugin' )
+const path = require( 'path' )
+const yargs = require( 'yargs' )
+const env = yargs.argv.env
+
+let filename = 'viewer'
+
+let outputFile, mode
+
+if ( env === 'build' ) {
+  mode = 'production'
+  outputFile = filename + '.min.js'
+} else {
+  mode = 'development'
+  outputFile = filename + '.js'
+}
+
+const config = {
+  mode: mode,
+  entry: path.resolve( __dirname + '/render_page/src/app.js' ),
+  target: 'web',
+  devtool: 'source-map',
+  output: {
+    path: path.resolve( __dirname + '/public/render' ) ,
+    filename: outputFile,
+  },
+  module: {
+    rules: [
+      {
+        test: /(\.jsx|\.js|\.ts|\.tsx)$/,
+        use: {
+          loader: 'babel-loader',
+        },
+        exclude: /(node_modules|bower_components)/,
+      },
+    ],
+  },
+  plugins: [
+    new CleanWebpackPlugin( { cleanStaleWebpackAssets: false } ),
+    new HtmlWebpackPlugin( { title: 'Speckle Viewer Example', template: 'render_page/src/example.html', filename: 'index.html' } )
+  ],
+  resolve: {
+    modules: [ path.resolve( './node_modules' ), path.resolve( '.render_page/src' ) ],
+    extensions: [ '.json', '.js' ],
+  },
+  devServer: {
+    contentBase: path.join( __dirname, 'example' ),
+    compress: false,
+    port: 9000,
+    serveIndex: true,
+    writeToDisk: true
+  }
+}
+
+module.exports = config
@@ -56,6 +56,7 @@ module.exports = {
    connection: connectionUri,
    migrations: {
      directory: migrationDirs
-    }
+    },
+    pool: { min: 2, max: 4 }
  }
 }
@@ -11,7 +11,7 @@ const { scalarResolvers, scalarSchemas } = require( './core/graph/scalars' )
 exports.init = async ( app ) => {
  let dirs = fs.readdirSync( `${appRoot}/modules` )

-  let moduleDirs = [ './core', './auth', './apiexplorer', './emails', './pwdreset', './serverinvites' ] // TODO: add './invites'
+  let moduleDirs = [ './core', './auth', './apiexplorer', './emails', './pwdreset', './serverinvites', './previews' ] // TODO: add './invites'

  // Stage 1: initialise all modules
  for ( let dir of moduleDirs ){
@@ -0,0 +1,102 @@
+/* istanbul ignore file */
+'use strict'
+
+const debug = require( 'debug' )
+const express = require( 'express' )
+const appRoot = require( 'app-root-path' )
+
+const cors = require( 'cors' )
+const { matomoMiddleware } = require( `${appRoot}/logging/matomoHelper` )
+const { contextMiddleware, validateScopes, authorizeResolver } = require( `${appRoot}/modules/shared` )
+
+const { getStream } = require( '../core/services/streams' )
+const { getObject } = require( '../core/services/objects' )
+const { getPreviewImage, createObjectPreview, getObjectPreviewInfo } = require( './services/previews' )
+
+exports.init = ( app, options ) => {
+  if ( process.env.DISABLE_PREVIEWS ) {
+    debug( 'speckle:modules' )( '📸 Object preview module is DISABLED' )
+  } else {
+    debug( 'speckle:modules' )( '📸 Init object preview module' )
+  }
+
+  let sendObjectPreview = async ( req, res, streamId, objectId ) => {
+    if ( process.env.DISABLE_PREVIEWS ) {
+      return res.sendFile( `${appRoot}/modules/previews/assets/no_preview.png` )
+    }
+
+    // Check if objectId is valid
+    const dbObj = await getObject( { streamId, objectId } )
+    if ( !dbObj ) {
+      return res.sendFile( `${appRoot}/modules/previews/assets/preview_error.png` )
+    }
+
+    // Get existing preview metadata
+    let previewInfo = await getObjectPreviewInfo( { streamId, objectId } )
+    if ( !previewInfo ) {
+      await createObjectPreview( { streamId, objectId, priority: 0 } )
+    }
+
+    let timestampStart = Date.now()
+
+    // Try for 10 sec of wall-clock to get the image (wait for preview generation)
+    while ( Date.now() < timestampStart + 10*1000 ) {
+      previewInfo = await getObjectPreviewInfo( { streamId, objectId } )
+      if ( previewInfo.previewStatus == 2 && previewInfo.preview ) {
+        break
+      }
+      await new Promise( ( resolve ) => {
+        setTimeout( resolve, 500 )
+      } )
+    }
+
+    if ( previewInfo.previewStatus != 2 || !previewInfo.preview ) {
+      return res.sendFile( `${appRoot}/modules/previews/assets/no_preview.png` )
+    }
+
+    let previewImgId = previewInfo.preview[req.params.angle]
+    if ( !previewImgId ) {
+      debug( 'speckle:errors' )( `Error: Preview angle '${req.params.angle}' not found for object ${streamId}:${objectId}` )
+      return res.sendFile( `${appRoot}/modules/previews/assets/preview_error.png` )
+    }
+    let previewImg = await getPreviewImage( { previewId: previewImgId } )
+    if ( !previewImg ) {
+      debug( 'speckle:errors' )( `Error: Preview image not found: ${previewImgId}` )
+      return res.sendFile( `${appRoot}/modules/previews/assets/preview_error.png` )
+    }
+
+    res.contentType( 'image/png' )
+    res.send( previewImg )
+  }
+
+  app.get( '/preview/:streamId/objects/:objectId/:angle', contextMiddleware, matomoMiddleware, async ( req, res ) => {
+
+    const stream = await getStream( { streamId: req.params.streamId, userId: req.context.userId } )
+
+    if ( !stream ) {
+      return res.status( 404 ).end()
+    }
+
+    if ( !stream.isPublic && req.context.auth === false ) {
+      return res.status( 401 ).end( )
+    }
+
+    if ( !stream.isPublic ) {
+      try {
+        await validateScopes( req.context.scopes, 'streams:read' )
+      } catch ( err ) {
+        return res.status( 401 ).end( )
+      }
+
+      try {
+        await authorizeResolver( req.context.userId, req.params.streamId, 'stream:reviewer' )
+      } catch ( err ) {
+        return res.status( 401 ).end( )
+      }
+    }
+
+    return sendObjectPreview( req, res, req.params.streamId, req.params.objectId )
+  } )
+}
+
+exports.finalize = () => {}
@@ -0,0 +1,25 @@
+/* istanbul ignore file */
+'use strict'
+
+exports.up = async knex => {
+  await knex.schema.createTable( 'object_preview', table => {
+    table.string( 'streamId', 10 ).references( 'id' ).inTable( 'streams' ).onDelete( 'cascade' )
+    table.string( 'objectId' ).notNullable( )
+    table.integer( 'previewStatus' ).notNullable( ).defaultTo( 0 )
+    table.integer( 'priority' ).notNullable( ).defaultTo( 1 )
+    table.timestamp( 'lastUpdate' ).notNullable( ).defaultTo( knex.fn.now( ) )
+    table.jsonb( 'preview' )
+    table.primary( [ 'streamId', 'objectId' ] )
+    table.index( [ 'previewStatus', 'priority', 'lastUpdate' ] )
+  } )
+
+  await knex.schema.createTable( 'previews', table => {
+    table.string( 'id' ).primary( )
+    table.binary( 'data' )
+  } )
+}
+
+exports.down = async knex => {
+  await knex.schema.dropTableIfExists( 'object_preview' )
+  await knex.schema.dropTableIfExists( 'previews' )
+}
@@ -0,0 +1,35 @@
+/* istanbul ignore file */
+'use strict'
+
+const appRoot = require( 'app-root-path' )
+const { async } = require('crypto-random-string')
+const knex = require( `${appRoot}/db/knex` )
+
+const ObjectPreview = ( ) => knex( 'object_preview' )
+const Previews = ( ) => knex( 'previews' )
+
+module.exports = {
+
+  async getObjectPreviewInfo( { streamId, objectId } ) {
+    return await ObjectPreview( ).select( '*' ).where( { streamId, objectId } ).first( )
+  },
+
+  async createObjectPreview ( { streamId, objectId, priority } ) {
+    let insertionObject = {
+      streamId,
+      objectId,
+      priority,
+      previewStatus: 0
+    }
+    let sqlQuery = ObjectPreview( ).insert( insertionObject ).toString( ) + ' on conflict do nothing'
+    await knex.raw( sqlQuery )
+  },
+
+  async getPreviewImage( { previewId } ) {
+    let previewRow = await Previews( ).where( { id: previewId } ).first( ).select( '*' )
+    if ( !previewRow ) {
+      return null
+    }
+    return previewRow.data
+  }
+}
				`@@ -0,0 +1 @@`
				`/! For license information please see Speckle.js.LICENSE.txt /`