DescribeTable is currently hard-coded to return PAY_PER_REQUEST billing
mode. Nevertheless, even in PAY_PER_REQUEST mode, the DescribeTable
operation must return a ProvisionedThroughput structure, listing both
ReadCapacityUnits and WriteCapacityUnits as 0. This requirement is not
stated in some DynamoDB documentation but is explictly mentioned in
https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_ProvisionedThroughput.html
Also in empirically, DynamoDB returns ProvisionedThroughput with zeros
even in PAY_PER_REQUEST mode. We even had an xfailing test to confirm this.
The ProvisionedThroughput structure being missing was a problem for
applications like DynamoDB connectors for Spark, if they implicitly
assume that ProvisionedThroughput is returned by DescribeTable, and
fail (as described in issue #11222) if it's outright missing.
So this patch adds the missing ProvisionedThroughput structure, and
the xfailing test starts to pass.
Note that this patch doesn't change the fact that attempting to set
a table to PROVISIONED billing mode is ignored: DescribeTable continues
to always return PAY_PER_REQUEST as the billing mode and zero as the
provisioned capacities.
Fixes#11222
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11298