func main()

in DynamoDB-SDK-Examples/golang/WorkingWithItems/updateItemConditional.go [25:76]

35 lines of code
4 McCabe index (conditional complexity)


func main() {
  
	// Create Session
    sess, err := session.NewSession(&aws.Config{
        Region: aws.String("eu-west-1")},
    )

    // Create DynamoDB client
    svc := dynamodb.New(sess)

	// Attribute to update
	address := Address{
			Road: "8123 Updated Rd, Main St, Hereville",
			Country: "USA",
	}

	// Keys for item
    item := Item{
        Pk: "jose.schneller@somewhere.com",
        Sk: "metadata",
    }

	// Marshal 
    expr, err := dynamodbattribute.MarshalMap(address)
    if err != nil {
        log.Fatalf("Got error marshalling item: %s", err)
    }

    key, err := dynamodbattribute.MarshalMap(item)
    if err != nil {
        log.Fatalf("Got error marshalling item: %s", err)
    }

    // Update Road Only if Country = USA
    input := &dynamodb.UpdateItemInput{
        TableName:                 aws.String("RetailDatabase"),
        Key:                       key,
        UpdateExpression:          aws.String("set address.road = :r"),
		ExpressionAttributeValues: expr,
		ReturnValues:              aws.String("UPDATED_NEW"),
		ConditionExpression: aws.String("address.country = :c"),
    }

	// Update item
    _, err = svc.UpdateItem(input)

    if err != nil {
        log.Fatalf("Got error calling UpdateItem: %s", err)
    }

    fmt.Println("Successfully updated item")
}