AWS API Gateway body mapping template to convert simple JSON into DynamoDB JSON

json-to-dynamodb-json.template

#set($tableName = $input.params("tableName"))
#set($inputRoot = $input.path('$'))
{
    "TableName": "$tableName",
    "Item": {
        "request_id": {
            "S": "$context.requestId"
        },
#foreach($key in $inputRoot.keySet())
#set($value = $inputRoot.get($key))
#set($class = $value.class)
##$class
#if($class == "class java.lang.Integer" 
    || $class == "class java.lang.Double"
    || $class == "class java.lang.Float"
    || $class == "class java.lang.BigDecimal"
    || $class == "class java.lang.BigInteger"
)
#set($type = "N")
#elseif($class == "class java.lang.Boolean")
#set($type = "BOOL")
#else
#set($type = "S")
#end
        "$key": {
            "$type": "$value"
        }#if($foreach.hasNext),#end

#end
    }
}