Add stl download for OpenSCAD and CadQuery IDEs

Resolves #330.

app/web/src/helpers/cadPackages/common.js

@@ -1,3 +1,40 @@
+import { STLLoader } from 'three/examples/jsm/loaders/STLLoader'
+
 export const lambdaBaseURL =
   process.env.CAD_LAMBDA_BASE_URL ||
   'https://2inlbple1b.execute-api.us-east-1.amazonaws.com/prod2'
+
+export const stlToGeometry = (url) =>
+  new Promise((resolve, reject) => {
+    new STLLoader().load(url, resolve, null, reject)
+  })
+
+export function createHealthyResponse({ date, data, consoleMessage, type }) {
+  return {
+    status: 'healthy',
+    objectData: {
+      type,
+      data: data,
+    },
+    message: {
+      type: 'message',
+      message: consoleMessage,
+      time: date,
+    },
+  }
+}
+
+export function createUnhealthyResponse(date, message = 'network issue') {
+  // TODO handle errors better
+  // I think we should display something overlayed on the viewer window something like "network issue try again"
+  // and in future I think we need timeouts differently as they maybe from a user trying to render something too complex
+  // or something with minkowski in it :/ either way something like "render timed out, try again or here are tips to reduce part complexity" with a link talking about $fn and minkowski etc
+  return {
+    status: 'error',
+    message: {
+      type: 'error',
+      message,
+      time: date,
+    },
+  }
+}