In this part we get the data from DynamoDB And return it.

Back in our query.js file we need to import the DynamoDB wrapper at the top of the file:

import * as dynamoDBLib from "../../libs/dynamodb-lib"

Next up we can create the parameters for our DynamoDB operation:

const params = {
  TableName: process.env.ListingsDB || "dev-listings",
}

Just a simple object that has the tablename. reason why we have the or operator is for when we test, Jest cannot pickup the .env file.

Next we have a try catch block that will help us fetch the data and return it:

try {
  const result = await dynamoDBLib.call("scan", params)

  if (result.Items.length === 0) {
    return "You have no listings"
  } else {
    return result.Items.map(i => ({
      listingId: i.listingId,
      coverPhoto: i.coverPhoto,
      listingName: i.listingName,
      listingDescription: i.listingDescription,
      listingType: i.listingType.map(m => ({
        name: m,
      })),
      listingLocation: i.listingLocation,
      listingActivities: i.listingActivities.map(k => ({
        name: k,
      })),
      specialType: i.specialType,
      specialAmount: i.specialAmount,
      rating: i.rating,
      guide: {
        Name: i.guide.name,
        Bio: i.guide.bio,
        Avatar: i.guide.avatar,
      },
      price: i.price,
      numberOfDays: i.numberOfDays,
    }))
  }

  // return result;
} catch (e) {
  return {
    message: e.message,
    code: "500x",
  }
}

🔋First we return a promise and execute a scan on Dynamo and pass through our params object.

🔋We have an if-else block to check if the is no listings, if they are, return all the listings

🔋Because we are returning an array we need to map over each element in the array and returning each field in the object.

🔋In the case of the ListingType & ListingActivies these are nested arrays within the listing object itself, which we look over to return each element in the array.

🔋 In the case of the guide all we are doing is returning back the properties in the guide object.

🔋 Lastly we return an error message and code in the case anything fails.

Next lets now go to Playground and test the query by executing the following query:

{
  getAllListings{
    listingId
    listingName
    listingLocation
    rating
    listingType{
      name
    }
  }
}

Now the function returns our data as we have shaped it: