Add updateAccountBalance

TODO.md

@@ -44,11 +44,16 @@ X Rearchitect updatePositions/updateBalances to use AppSync JS Resolvers
 
 ##### Current Task
 
-- On PositionUpdatedEvent, update account balance with Position.marketvalue
-- On BankTransactionSavedEvent, update account balance with Transaction.amount
+X On PositionUpdatedEvent, update account balance with Position.marketvalue
+X On BankTransactionSavedEvent, update account balance with Transaction.amount
+-- Create new DLQ for updateAccountBalance
+
+- review bookValue formula should be = price \* shares + commission
+- Draw diagram
 
 ##### Future Task
 
+- hide dropdowns after creating a new symbol, payee, category, etc
 - add tests to updatePosition Lambda
 - Update dashboard to pull positions and totals - requires new API getPositions(userId)
 - create L3 constructs for AppSync CDK

backend/lib/api-stack.ts

@@ -597,6 +597,31 @@ export class ApiStack extends Stack {
       })
     );
 
+    const updateAccountBalanceFunction = new NodejsFunction(this, 'UpdateAccountBalance', {
+      runtime: Runtime.NODEJS_22_X,
+      functionName: `${props.appName}-${props.envName}-UpdateAccountBalance`,
+      handler: 'handler',
+      entry: path.resolve(__dirname, '../src/lambda/updateAccountbalance/main.ts'),
+      memorySize: 384,
+      timeout: Duration.seconds(5),
+      tracing: Tracing.ACTIVE,
+      layers: [adotJavscriptLayer],
+      environment: {
+        REGION: Stack.of(this).region,
+        DATA_TABLE_NAME: dataTable.tableName,
+        AWS_LAMBDA_EXEC_WRAPPER: '/opt/otel-handler',
+      },
+      deadLetterQueue: updatePositionDLQ,
+    });
+    // Add permissions to call DynamoDB
+    updateAccountBalanceFunction.addToRolePolicy(
+      new PolicyStatement({
+        effect: Effect.ALLOW,
+        actions: ['dynamodb:UpdateItem'],
+        resources: [dataTable.tableArn],
+      })
+    );
+
     /***
      *** AWS EventBridge - Event Bus Rules
      ***/
@@ -613,12 +638,27 @@ export class ApiStack extends Stack {
     });
     investmentTransactionSavedRule.addTarget(
       new LambdaFunction(updatePositionFunction, {
-        //deadLetterQueue: SqsQueue,
         maxEventAge: Duration.hours(2),
         retryAttempts: 2,
       })
     );
 
+    // EventBus Rule - PositionUpdatedEvent and BankTransactionSavedEvent
+    const transactionUpdatedEventRule = new Rule(this, 'PositionUpdatedEvent', {
+      ruleName: `${props.appName}-TransactionUpdatedEvent-${props.envName}`,
+      description: 'TransactionUdpatedEvent',
+      eventBus: eventBus,
+      eventPattern: {
+        source: ['custom.pecuniary'],
+        detailType: ['PositionUpdatedEvent', 'BankTransactionSavedEvent'],
+      },
+    });
+    transactionUpdatedEventRule.addTarget(
+      new LambdaFunction(updateAccountBalanceFunction, {
+        maxEventAge: Duration.hours(2),
+        retryAttempts: 2,
+      })
+    );
     /***
      *** Outputs
      ***/
@@ -640,6 +680,9 @@ export class ApiStack extends Stack {
     new CfnOutput(this, 'InvestmentTransactionSavedRuleArn', {
       value: investmentTransactionSavedRule.ruleArn,
     });
+    new CfnOutput(this, 'TransactionUpdatedEventRule', {
+      value: transactionUpdatedEventRule.ruleArn,
+    });
 
     // Lambda functions
     new CfnOutput(this, 'UpdatePositionFunctionArn', {

backend/src/lambda/updateAccountBalance/main.ts

@@ -0,0 +1,46 @@
+import { EventBridgeEvent } from 'aws-lambda';
+import { UpdateItemCommandInput, UpdateItemCommand } from '@aws-sdk/client-dynamodb';
+import { marshall } from '@aws-sdk/util-dynamodb';
+import dynamoDbCommand from './utils/dynamoDbClient';
+
+type EventData = {
+  accountId: string;
+  amount: number;
+};
+
+const handler = async (event: EventBridgeEvent<string, EventData>) => {
+  const data = parseEvent(event);
+
+  console.log(`🔔 Received event: ${JSON.stringify(data)}`);
+
+  if (!data || !data.accountId || !data.amount) {
+    throw new Error(`🛑 No data found in event ${data}`);
+  }
+
+  // update dynamodb account
+  const params: UpdateItemCommandInput = {
+    TableName: process.env.DATA_TABLE_NAME,
+    Key: marshall({ pk: `acc#${data.accountId}` }),
+    UpdateExpression: 'SET balance = balance + :amount, updatedAt = :updatedAt',
+    ExpressionAttributeValues: marshall({
+      ':amount': data.amount,
+      ':updatedAt': new Date().toISOString(),
+    }),
+    ReturnValues: 'UPDATED_NEW',
+  };
+  const result = await dynamoDbCommand(new UpdateItemCommand(params));
+
+  if (result.$metadata.httpStatusCode !== 200) {
+    throw new Error(`🛑 Could not update account ${data.accountId}`);
+  }
+};
+
+function parseEvent(event: EventBridgeEvent<string, EventData>): EventData {
+  const eventString: string = JSON.stringify(event);
+
+  console.debug(`🕧 Received event: ${eventString}`);
+
+  return JSON.parse(eventString).detail;
+}
+
+module.exports = { handler };