fix(lwm2m): table with objects is not needed

cdk/backend.ts

@@ -13,7 +13,6 @@ const packagesInLayer: string[] = [
 	'@nordicsemiconductor/timestream-helpers',
 	'@hello.nrfcloud.com/proto-lwm2m',
 	'jsonata',
-	'ulid',
 ]
 const pack = async (
 	id: string,

cdk/resources/LwM2M.ts

@@ -1,7 +1,5 @@
 import { Construct } from 'constructs'
 import {
-	aws_dynamodb as DynamoDB,
-	RemovalPolicy,
 	Duration,
 	aws_iam as IAM,
 	aws_iot as IoT,
@@ -15,7 +13,6 @@ import type { PackedLambda } from '../backend'
  * Contains resources that provide LwM2M based data for devices
  */
 export class LwM2M extends Construct {
-	public readonly table: DynamoDB.ITable
 	constructor(
 		parent: Construct,
 		{
@@ -30,16 +27,6 @@ export class LwM2M extends Construct {
 	) {
 		super(parent, 'LwM2M')
 
-		this.table = new DynamoDB.Table(this, 'table', {
-			billingMode: DynamoDB.BillingMode.PAY_PER_REQUEST,
-			partitionKey: {
-				name: 'id',
-				type: DynamoDB.AttributeType.STRING,
-			},
-			timeToLiveAttribute: 'ttl',
-			removalPolicy: RemovalPolicy.DESTROY,
-		})
-
 		const fn = new Lambda.Function(this, 'updatesToLwM2M', {
 			handler: lambdaSources.updatesToLwM2M.handler,
 			architecture: Lambda.Architecture.ARM_64,
@@ -52,7 +39,6 @@ export class LwM2M extends Construct {
 			layers: [baseLayer],
 			environment: {
 				VERSION: this.node.tryGetContext('version'),
-				TABLE_NAME: this.table.tableName,
 			},
 			initialPolicy: [
 				new IAM.PolicyStatement({
@@ -63,8 +49,6 @@ export class LwM2M extends Construct {
 			logRetention: Logs.RetentionDays.ONE_WEEK,
 		})
 
-		this.table.grantWriteData(fn)
-
 		const ruleRole = new IAM.Role(this, 'ruleRole', {
 			assumedBy: new IAM.ServicePrincipal(
 				'iot.amazonaws.com',

cdk/stacks/BackendStack.ts

@@ -97,7 +97,7 @@ export class BackendStack extends Stack {
 			lambdaSources,
 		})
 
-		const lwm2m = new LwM2M(this, {
+		new LwM2M(this, {
 			lambdaSources,
 			baseLayer,
 		})
@@ -128,11 +128,6 @@ export class BackendStack extends Stack {
 			value: userAuthentication.identityPool.ref,
 			exportName: `${this.stackName}:identityPoolId`,
 		})
-
-		new CfnOutput(this, 'lwm2mTableName', {
-			value: lwm2m.table.tableName,
-			exportName: `${this.stackName}:lwm2mTableName`,
-		})
 	}
 }
 

lambda/updatesToLwM2M.ts

@@ -1,75 +1,19 @@
-import {
-	AttributeValue,
-	BatchWriteItemCommand,
-	DynamoDBClient,
-} from '@aws-sdk/client-dynamodb'
 import {
 	IoTDataPlaneClient,
 	UpdateThingShadowCommand,
 } from '@aws-sdk/client-iot-data-plane'
-import { fromEnv } from '@nordicsemiconductor/from-env'
 import { transformShadowUpdateToLwM2M } from '../lwm2m/transformShadowUpdateToLwM2M.js'
 import {
 	models,
 	type LwM2MObjectInstance,
 } from '@hello.nrfcloud.com/proto-lwm2m'
-import { ulid } from 'ulid'
 import { objectsToShadow } from '../lwm2m/objectsToShadow.js'
 
-const { tableName } = fromEnv({
-	tableName: 'TABLE_NAME',
-})(process.env)
-
-const db = new DynamoDBClient({})
 const iotData = new IoTDataPlaneClient({})
 const transformUpdate = transformShadowUpdateToLwM2M(
 	models['asset_tracker_v2+AWS'].transforms,
 )
 
-const persist = async (
-	deviceId: string,
-	objects: LwM2MObjectInstance[],
-): Promise<void> => {
-	await db.send(
-		new BatchWriteItemCommand({
-			RequestItems: {
-				[tableName]: objects.map((object) => ({
-					PutRequest: {
-						Item: {
-							id: { S: ulid() },
-							deviceId: { S: deviceId },
-							ObjectId: { N: object.ObjectID.toString() },
-							ObjectVersion:
-								object.ObjectVersion !== undefined
-									? { S: object.ObjectVersion }
-									: { S: '1.0' },
-							Resources: {
-								M: Object.entries(object.Resources).reduce(
-									(map, [k, v]) => ({
-										...map,
-										[k]: convertValue(v),
-									}),
-									{},
-								),
-							},
-							ttl: {
-								N: Math.round(Date.now() / 1000 + 30 * 24 * 60 * 60).toString(),
-							},
-						},
-					},
-				})),
-			},
-		}),
-	)
-}
-
-const convertValue = (v: string | number | boolean | Date): AttributeValue => {
-	if (typeof v === 'number') return { N: v.toString() }
-	if (typeof v === 'boolean') return { BOOL: v }
-	if (typeof v === 'object' && v instanceof Date) return { S: v.toISOString() }
-	return { S: v }
-}
-
 const updateShadow = async (
 	deviceId: string,
 	objects: LwM2MObjectInstance[],
@@ -111,6 +55,5 @@ export const handler = async (event: {
 		}),
 	)
 
-	void persist(deviceId, objects)
 	void updateShadow(deviceId, objects)
 }

package.json

@@ -91,7 +91,6 @@
     "@nordicsemiconductor/timestream-helpers": "6.0.1",
     "@sinclair/typebox": "0.31.23",
     "ajv": "8.12.0",
-    "jsonata": "2.0.3",
-    "ulid": "2.3.0"
+    "jsonata": "2.0.3"
   }
 }