How to Create Dynamodb Global Secondary Index using AWS CLI?

Question

The AWS CLI for Dynamodb create-table is a little bit confusion when it comes to create global secondary index. In the CLI document, it says global secondary index could be expressed with the following expression (shorthand):

IndexName=string,KeySchema=[{AttributeName=string,KeyType=string},{AttributeName=string,KeyType=string}],Projection={ProjectionType=string,NonKeyAttributes=[string,string]},ProvisionedThroughput={ReadCapacityUnits=long,WriteCapacityUnits=long} ...

My interpretation is, I should do

--global-secondary-indexes IndexName=requesterIndex,Projection={ProjectionType=ALL},ProvisionedThroughput={ReadCapacityUnits=1,WriteCapacityUnits=1}

Note that I am not including KeySchema here to deduce complexity. The console gives me the following error:

Parameter validation failed:
Missing required parameter in GlobalSecondaryIndexes[0]: "KeySchema"
Unknown parameter in GlobalSecondaryIndexes[0]: "WriteCapacityUnits", must be one of: IndexName, KeySchema, Projection, ProvisionedThroughput
Invalid type for parameter GlobalSecondaryIndexes[0].ProvisionedThroughput, value: ReadCapacityUnits=1, type: <class 'str'>, valid types: <class 'dict'>

So somehow AWS CLI does not recognize the map expression for ProvisionedThroughput. I tried several ways to express it and could not make it work. I also failed to find any web page in Google describing how to do it.

Answer 1

• Define the table structure in a JSON file, including the index structures. Use following to create a template structure. aws dynamodb create-table --generate-cli-skeleton

• Run the cli command with the table definition input json aws dynamodb create-table --cli-input-json file://path-to-yourtable-definition.json

Answer 2

This is the cli call I used to create the Reply sample in the aws documentation from the command line. The $EP i used at the end can be set in the environment to EP="--endpoint-url http://localhost:8000" to create the table on your local dynamodb instead of aws.

aws dynamodb create-table --table-name Reply --attribute-definitions \
AttributeName=Id,AttributeType=S AttributeName=ReplyDateTime,AttributeType=S \
AttributeName=PostedBy,AttributeType=S AttributeName=Message,AttributeType=S \
--key-schema AttributeName=Id,KeyType=HASH \
AttributeName=ReplyDateTime,KeyType=RANGE --global-secondary-indexes \
IndexName=PostedBy-Message-Index,KeySchema=["\
{AttributeName=PostedBy,KeyType=HASH}","\
{AttributeName=Message,KeyType=RANGE}"],Projection="{ProjectionType=INCLUDE \
,NonKeyAttributes=["ReplyDateTime"]}",ProvisionedThroughput="\
{ReadCapacityUnits=10,WriteCapacityUnits=10}" --provisioned-throughput \
ReadCapacityUnits=5,WriteCapacityUnits=4 $EP

Answer 3

Read through AWS CLI source code on Github, it could parse double quote content. So adding double quote in the script solved the issue. There is the new code -

--global-secondary-indexes IndexName=requesterIndex,Projection={ProjectionType=ALL},ProvisionedThroughput="{ReadCapacityUnits=${CURRENT_READUNIT},WriteCapacityUnits=${CURRENT_WRITEUNIT}}"