AWS SDK for Go Code Examples for Amazon DynamoDB

Purpose

These examples demonstrates how to perform several DynamoDB operations.

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

CreateTable/CreateTable.go

This example creates a DynamoDB table.

go run CreateTable.go -t TABLE

TABLE is the name of the table.

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

The table has two attributes:

Year is an integer.
Title is a string.

CreateTableItem/CreateTableItem.go

Creates a new item in a DynamoDB table.

go run CreateTableItem -d TABLE -y YEAR -t TITLE -p PLOT -r RATING

TABLE is the name of the table.
YEAR is the year that the movie was released.
TITLE is the title of the movie.
PLOT is the plot of the movie.
RATING is the rating, from 0.0 to 10.0, of the movie.

The unit test accepts similar values in config.json.

DeleteItem/DeleteItem.go

This example deletes an item from a DynamoDB table.

go run DeleteTable.go -t TABLE -m MOVIE -y YEAR

TABLE is the name of the table containing the item to delete.
MOVIE is the name of the movie item to delete.
YEAR is when the movie was released.

The unit test mocks the DynamoDB service and the DeleteItem function.

GetItem/GetItem.go

This example retrieves an item from a DynamoDB table.

go run GetItem.go -t TABLE -n NAME -y YEAR

TABLE is the name of the table.
NAME is the name of the movie.
YEAR is when the movie was released.

The unit test mocks the DynamoDB service and GetItem function.

ListTables/ListTables.go

This example lists your DynamoDB tables.

go run ListTables.go [-l LIMIT]

LIMIT is how many tables to show. The default is 100. If this value is less than zero, it is set to 10.

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

LoadTableItems/LoadTableItems.go

This example adds items from a JSON file to a table.

go run LoadTableItems.go -j JSON-FILE -d TABLE

JSON-FILE is the name of the JSON file containing the items to load into the table.
TABLE is the name of the table.

The unit test accepts similar values in config.json.

ScanItems/ScanItems.go

This example uses the Expression Builder package to scan a table for items that fit the criteria.

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

TABLE is the name of the table.
RATING is the minimum rating, from 0.0 to 1.0, given to the movies to retrieve.
YEAR is the year when the movies were released.

The unit test mocks the DynamoDB service and Scan function.

UpdateItem/UpdateItem.go

This example updates the year and rating of a movie in a table.

go run UpdateItem.go -t TABLE -m MOVIE -y YEAR -r RATING

TABLE is the name of the table.
MOVIE is the name of the movie.
YEAR is the year the movie was released.
RATING is the rating, from 0.0 to 1.0.

The unit test accepts similar values from config.json.

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 -test.v

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