feat(start_driver_trip): validate no in progress trip

start_driver_trip.js

@@ -2,9 +2,14 @@ const aws = require('aws-sdk');
 const moment = require('moment');
 
 const TripsTableName = process.env.dynamodb_trips_table_name;
+const TripsIndexName = process.env.dynamodb_trips_index_name;
 
 const dynamoDB = new aws.DynamoDB.DocumentClient();
 
+function isEmpty(obj) {
+  return Object.keys(obj).length === 0 && obj.constructor === Object;
+}
+
 async function startTrip(tripId, userId) {
   const timestamp = moment().format('YYYY-MM-DDTHH:mm:ss-04:00');
   const newStatus = 'in_progress';
@@ -15,11 +20,11 @@ async function startTrip(tripId, userId) {
       trip_id: tripId
     },
     UpdateExpression:
-      'set trip_status = :new_status, current_point = :val, updated_at = :now',
+      'set trip_status = :new_status, current_point = :zero, updated_at = :now',
     ConditionExpression:
       'trip_status = :expected_status and driver_id = :self',
     ExpressionAttributeValues: {
-      ':val': 0,
+      ':zero': 0,
       ':new_status': newStatus,
       ':now': timestamp,
       ':expected_status': expectedStatus,
@@ -31,10 +36,37 @@ async function startTrip(tripId, userId) {
   return data.Attributes;
 }
 
+async function getTripInProgress(userId) {
+  const params = {
+    TableName: TripsTableName,
+    IndexName: TripsIndexName,
+    KeyConditionExpression: 'driver_id = :userId',
+    FilterExpression:
+      'trip_status = :expectedStatus',
+    ExpressionAttributeValues: {
+      ':userId': userId,
+      ':expectedStatus': 'in_progress'
+    }
+  };
+  const data = await dynamoDB.query(params).promise();
+  return data.Items[0];
+}
+
 exports.handler = async (event) => {
   const userId = event.requestContext.authorizer.user_id;
   const tripId = event.pathParameters.trip;
 
+  const tripInProgress = await getTripInProgress(userId);
+  if (tripInProgress && !isEmpty(tripInProgress)) {
+    return {
+      statusCode: 409,
+      headers: { 'Access-Control-Allow-Origin': '*' },
+      body: JSON.stringify({
+        action: 'start', success: false, resource: 'trip', message: 'Trip in progress conflict'
+      })
+    };
+  }
+
   await startTrip(tripId, userId);
   const responseBody = {
     action: 'start',