his patch adds a statistics framework to Alternator: Executor has (for
each shard) a _stats object which contains counters for various events,
and also is in charge of making these counters visible via Scylla's regular
metrics API (http://localhost:9180/metrics).
This patch includes a counter for each of DynamoDB's operation types,
and we increase the ones we support when handled. We also added counters
for total operations and unsupported operations (operation types we don't
yet handle). In the future we can easily add many more counters: Define
the counter in stats.hh, export it in stats.cc, and increment it in
where relevant in executor.cc (or server.cc).
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Instead of blindly returning "localhost:8000" in response to
DescribeEndpoints and for sure causing us problems in the future,
the right thing to do is to return the same domain name which the
user originally used to get to us, be it "localhost:8000" or
"some.domain.name:1234". But how can we know what this domain name
was? Easy - this is why HTTP 1.1 added a mandatory "Host:" header,
and the DynamoDB driver I tested (boto3) adds it as expected,
indeed with the expected value of "localhost:8000" on my local setup.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
DescribeEndpoints is not a very important API (and by default, clients
don't use it) but I wanted to understand how DynamoDB responds to it,
and what better way than to write a test :-)
And then, if we already have a test, let's implement this request in
Scylla as well. This is a silly implementation, which always returns
"localhost:8000". In the future, this will need to be configurable -
we're not supposed here to return *this* server's IP address, but rather
a domain name which can be used to get to all servers.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Add an initial UpdateItem implementation. As PutItem and GetItem we
are still limited to string attributes. This initial implementation
of UpdateItem implements only the "PUT" action (not "DELETE" and
certainly not "ADD") and not any of the more advanced options.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Add an initial implementation of Delete table, enough for making the
pytest --local test_table.py::test_create_and_delete_table
Pass.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
This initial implementation is enough to pass a test of getting a
failure for a non-existant table -
test_table.py::test_describe_table_non_existent_table
and to recognize an existing table. But it's still missing a lot
of fields for an existing table (among others, the schema).
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
The interface works on port 8000 by default and provides
the most basic alternator operations - it's an incomplete
set without validation, meant to allow testing as early as possible.