dynamodb/

README

AWS SDK for Go V2 code examples for Amazon DynamoDB

Purpose

These examples demonstrates how to perform several DynamoDB operations using version 2 of the AWS SDK for Go.

Prerequisites

You must have an AWS account, and have your default credentials and AWS Region configured as described in Configuring the AWS SDK for Go in the AWS SDK for Go Developer Guide.

Running the code

DescribeTable/DescribeTablev2.go

This example lists the following properties of a DynamoDB table.

• Number of items
• Size, in bytes
• Status, such as Active

go run DescribeTablev2.go -t TABLE

• TABLE is the name of the table.

The unit test accepts a similar value in config.json.

ScanItems/ScanItemsv2.go

This example retrieves the Amazon DynamoDB items with a rating above a specified value in a specified year.

go run ScanItemsv2.go -t TABLE -r RATING -y YEAR

• TABLE is the name of the table.
• RATING is the rating of the item, from 0.0 to 10.0.
• YEAR is the year of the item, which must be greater than 1900.

The unit test accepts similar values in config.json.

Using Amazon DynamoDB local

You can test your Go code against a local version of Amazon DynamoDB. Doing so elimiates the possibility of incurring charges against your Amazon account.

For information on installing the local version of Amazon DynamoDB, see Setting Up DynamoDB Local (Downloadable Version) in the Amazon DynamoDB Developer Guide.

To run the local version of Amazon DynamoDB, perform the following steps:

1. Navigate to where you've installed the local version of Amazon DynamoDB.
2. Run the following command:

   java -Djava.library.path=./DynamoDBLocal_lib -jar DynamoDBLocal.jar -sharedDb
   

If you don't care whether any information is saved between session, add the -inMemory flag.

In your Go code, change the config object you create from:

cfg, err := config.LoadDefaultConfig(context.TODO())

to:

cfg, err := config.LoadDefaultConfig(context.TODO(),
    config.WithEndpointResolver(aws.EndpointResolverFunc(
        func(service, region string) (aws.Endpoint, error) {
            return aws.Endpoint{URL: "https://localhost:8000"}, nil
    })),
)

Notes

• We recommend that you grant this code least privilege, or at most the minimum permissions required to perform the task. For more information, see Grant Least Privilege in the AWS Identity and Access Management User Guide.
• This code has not been tested in all AWS Regions. Some AWS services are available only in specific Regions.
• Running this code might result in charges to your AWS account.

Running the unit tests

Unit tests should delete any resources they create. However, they might result in charges to your AWS account.

To run a unit test, enter:

go test

You should see something like the following, where PATH is the path to the folder containing the Go files:

PASS
ok      PATH 6.593s

If you want to see any log messages, enter:

go test -v

You should see some additional log messages. The last two lines should be similar to the previous output shown.

Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. SPDX-License-Identifier: Apache-2.0