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Co-authored-by: Andrew Meyer <[email protected]>
Co-authored-by: LJ <[email protected]>

examples/example-node-telemetry/README.md

@@ -1,27 +1,55 @@
-# Telemetry demo app using data ingest and Atlas Charts
+# Telemetry demo app using Data Ingest and Atlas Charts
 
-A [node.js](https://nodejs.org) application to demonstrate how to use [Atlas Device Sync](https://www.mongodb.com/atlas/app-services/device-sync) and [Realm JavaScript](https://github.com/realm/realm-js) to read sensor data, store the data in [Atlas](https://www.mongodb.com/atlas), and visualize it with [Charts](https://www.mongodb.com/products/charts).
+A [Node.js](https://nodejs.org) application to demonstrate how to use [Atlas Device Sync](https://www.mongodb.com/atlas/app-services/device-sync) and the [Realm Node.js SDK](https://www.mongodb.com/docs/realm/sdk/node/) to read sensor data, store the data in [Atlas](https://www.mongodb.com/atlas), and visualize it with [Atlas Charts](https://www.mongodb.com/products/charts). [Data Ingest](https://www.mongodb.com/docs/atlas/app-services/sync/configure/sync-settings/#data-ingest) is enabled since this app uses insert-only workloads.
 
-The file structure is as follows:
+## Project Structure
+
+The following shows the project structure and the most relevant files.
 
 ```
-├── README.md
-├── package.json
 ├── src
-│   ├── app.ts
-│   ├── config.ts
-│   └── models
-│       ├── machine_info.ts
-│       └── sensor_reading.ts
+│   ├── models
+│   │   ├── machine_info.ts
+│   │   └── sensor_reading.ts
+│   ├── app.ts
+│   └── config.ts
+├── package.json
+└── README.md
 ```
 
 * `src/app.ts` - the actual application
-* `src/config.ts` - contains the configuration (app id)
+* `src/config.ts` - contains the configuration (Atlas App ID)
 * `src/models/` - the model classes
 
-## Altas App Services
+## Use Cases
+
+This app focuses on showing how to use Data Ingest for heavy client-side insert-only workloads. It specifically addresses the following points:
+
+* Using the Data Ingest sync strategy via asymmetric Realm objects.
+* Reading sensor data (system load averages, uptime, and free memory).
+* Inserting sensor data every few seconds and syncing it to Atlas.
+* (The data in Atlas can be visualized via Atlas Charts, but since this is a Node.js app, the visualization is not shown.)
+
+### Realm Details
+
+* RealmJS version: ^12.1.0
+* Device Sync type: [Flexible](https://www.mongodb.com/docs/realm/sdk/node/sync/flexible-sync/) with [Data Ingest](https://www.mongodb.com/docs/atlas/app-services/sync/configure/sync-settings/#data-ingest)
+
+## Getting Started
+
+### Prerequisites
+
+* [Node.js](https://nodejs.org/)
+
+### Set Up an Atlas App Services App
+
+To sync Realm data you must first:
+
+1. [Create an App Services App](https://www.mongodb.com/docs/atlas/app-services/manage-apps/create/create-with-ui/)
+2. [Enable Anonymous Authentication](https://www.mongodb.com/docs/atlas/app-services/authentication/anonymous/)
+3. [Enable Flexible Sync](https://www.mongodb.com/docs/atlas/app-services/sync/configure/enable-sync/) with **Development Mode** on.
 
-To use the app together with Atlas App Services, you need to create an Atlas database and collection. Moreover, you need to create App service and enable Device Sync. 
+After running the client and seeing the available collection in Atlas, [set write permissions](https://www.mongodb.com/docs/atlas/app-services/rules/roles/#define-roles---permissions) for the collection.
 
 The schema to use (App Services / Data Access / Schema):
 

examples/example-node-telemetry/package.json

@@ -3,10 +3,11 @@
   "private": true,
   "version": "0.1.0",
   "description": "A demonstration of how to use data ingest to store and visualize sensor data",
-  "main": "index.js",
+  "main": "src/app.ts",
   "scripts": {
     "build": "tsc -p tsconfig.build.json",
     "lint": "eslint --ext .js,.mjs,.ts .",
+    "start": "npm run build && node dist/app.js",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "keywords": [],
@@ -22,6 +23,7 @@
     "realm": "^12.1.0"
   },
   "devDependencies": {
+    "@types/debug": "^4.1.8",
     "@types/node": "^20.5.7",
     "eslint": "^8.48.0",
     "typescript": "^4.9.5"

examples/example-node-telemetry/src/app.ts

@@ -16,7 +16,7 @@
 //
 ////////////////////////////////////////////////////////////////////////////
 
-import * as os from "os";
+import os from "node:os";
 import { machineId } from "node-machine-id";
 
 import createDebug from "debug";
@@ -53,15 +53,19 @@ async function readMachineInfo() {
 }
 
 async function main() {
-  // Initialize the app using the app id. You need to copy it from https://realm.mongodb.com
+  // Initialize the app using the App ID. To copy it, see:
+  // https://www.mongodb.com/docs/atlas/app-services/apps/metadata/#std-label-find-your-app-id
   const app = new Realm.App(config.appId);
   debug(`App ${config.appId} has been initiated`);
-  // We are using an anonymous user, and you can switch to any auth provider if needed
+
+  // We are using an anonymous user for this example app, but you can modify this to
+  // use any of the available auth providers.
   debug(`Logging in`);
   const user = await app.logIn(Realm.Credentials.anonymous());
   debug(`User ${user.id} has been logged in`);
-  // For data ingest (`asymmetric: true` in `SensorReading`) you don't need any
-  // subscriptions for flexible sync
+
+  // For Data Ingest (`asymmetric: true` in the `SensorReading` schema) you don't need
+  // to set up any subscriptions for flexible sync since no data will be synced to the device.
   debug("Opening Realm");
   const realm = await Realm.open({
     schema: [SensorReading, MachineInfo],
@@ -71,18 +75,18 @@ async function main() {
     },
   });
 
-  // The metadata about the computer will not change
+  // The metadata about the computer will not change, thus we only read it once.
   const machineInfo = await readMachineInfo();
   const intervalId = setInterval(() => {
     const now = new Date();
     const measurement = readSensorData();
-    const obj = {
+    const obj: SensorReading = {
       timestamp: now,
       machineInfo,
       ...measurement,
     };
     debug("Writing new sensor reading");
-    realm.write(() => realm.create(SensorReading.name, obj));
+    realm.write(() => realm.create(SensorReading, obj));
   }, tenSeconds);
 
   // Catch CTRL-C in a nice way
@@ -93,7 +97,7 @@ async function main() {
     clearInterval(intervalId);
     debug("Sync any outstanding changes");
     await realm.syncSession?.uploadAllLocalChanges();
-    debug("Cloing Realm");
+    debug("Closing Realm");
     realm.close();
     debug(`Logging out user ${user.id}`);
     await user.logOut();

examples/example-node-telemetry/src/models/sensor_reading.ts

@@ -24,19 +24,19 @@ export class SensorReading extends Realm.Object {
   timestamp!: Date;
   uptime!: number;
   freemem!: number;
-  loadAvg!: [number];
+  loadAvg!: Realm.List<number>;
   machineInfo!: MachineInfo;
 
   static schema: ObjectSchema = {
     name: "SensorReading",
     asymmetric: true,
     primaryKey: "_id",
     properties: {
-      _id: { type: "objectId", default: () => new BSON.ObjectID() },
-      timestamp: { type: "date", optional: false, default: () => new Date() },
+      _id: { type: "objectId", default: () => new BSON.ObjectId() },
+      timestamp: "date",
       uptime: "float",
       freemem: "int",
-      loadAvg: { type: "list", objectType: "float" },
+      loadAvg: "float[]",
       machineInfo: "MachineInfo",
     },
   };

examples/example-node-telemetry/tsconfig.json

@@ -1,5 +1,4 @@
 {
-	"extends": "../../tsconfig.json",
 	"compilerOptions": {
 		"target": "es2018",
 		"moduleResolution": "node",