Add elasticache user and group support

[swhite-oreilly]

This PR includes two new modules for Elasticache Users and User Groups.

Also including a filter update to ignore the default subnet for elasticache.

Testing

Elasticache users and users groups were created. using the setup code mentioned below, and then AWS Nuke was used to clean these resources up, specifying ElasticacheUser and ElasticacheUserGroup. The resources were handle as expected:

...
us-east-1 - ElasticacheUserGroup - myusergroup - would remove
...
us-east-1 - ElasticacheSubnetGroup - default - Cannot delete default subnet group
us-east-1 - ElasticacheSubnetGroup - mygroup - would remove
...
us-east-1 - ElasticacheUser - default - Cannot delete default user
us-east-1 - ElasticacheUser - user1 - would remove

Setup code

# Create a Redis cluster
echo "Creating Redis cluster"
aws elasticache create-cache-cluster \
--cache-cluster-id my-cluster \
--cache-node-type cache.t4g.micro \
--engine redis \
--num-cache-nodes 1 \
--cache-parameter-group default.redis7

# Create a Memcached cluster
echo "Creating Memcached cluster"
aws elasticache create-cache-cluster \
--cache-cluster-id my-memcached-cluster \
--cache-node-type cache.r4.large \
--engine memcached \
--engine-version 1.4.24 \
--cache-parameter-group default.memcached1.4 \
--num-cache-nodes 3

echo "Getting a subnet from the default VPC"
DEFAULT_VPC_ID=$(aws ec2 describe-vpcs --filters "Name=isDefault,Values=true" --query 'Vpcs[0].VpcId' --output text)

SUBNET_ID=$(aws ec2 describe-subnets --filters "Name=vpc-id,Values=$DEFAULT_VPC_ID" "Name=availability-zone,Values=us-east-1*" --query 'Subnets[0].SubnetId' --output text)
echo "Using subnet $SUBNET_ID"

# Create an elasticache subnet group (Note: This command will fail if the subnet does not exist)
echo "Creating elasticache subnet group"
aws elasticache create-cache-subnet-group \
    --cache-subnet-group-name "mygroup" \
    --cache-subnet-group-description "my subnet group" \
    --subnet-ids "$SUBNET_ID"

# Create a elasticache parameter group
echo "Creating elasticache parameter group"
aws elasticache create-cache-parameter-group \
    --cache-parameter-group-family "redis5.0" \
    --cache-parameter-group-name "mygroup" \
    --description "mygroup"

# Create a elasticache user
echo "Creating elasticache user"
aws elasticache create-user \
    --user-id user1 \
    --user-name myUser \
    --passwords PASSWORD_STRING \
    --engine redis \
    --access-string "on ~app::* -@all +@read"

# Create a elasticache user group
echo "Creating elasticache user group"
aws elasticache create-user-group \
    --user-group-id myusergroup \
    --engine redis \
    --user-ids default

[bjoernhaeuser]

This properly needs paging as well, no?

[swhite-oreilly]

@bjoernhaeuser paging added.

[bjoernhaeuser]

This properly needs paging as well, no?

[swhite-oreilly]

@bjoernhaeuser paging added.

[der-eismann]

Sorry for the late reply - would you mind adding properties for both resources as well?

[swhite-oreilly]

@der-eismann I have added properties to both resources. Are these sufficient or are there additional properties you would like to see?

[der-eismann]

No these are fine, thanks!