With this patch, LocalSecondaryIndexes can be added to a table
during its creation. The implementation is heavily shared
with GlobalSecondaryIndexes and as such suffers from the same TODOs:
projections, describing more details in DescribeTable, etc.
This adds a "alternator-address" and "alternator-port" configuration
options to the Docker image, so people can enable Alternator with
"docker run" with:
docker run --name some-scylla -d <image> --alternator-port=8080
Message-Id: <20190902110920.19269-1-penberg@scylladb.com>
The test_gsi_3, involving creating a GSI with two key columns which weren't
previously a base key, now passes, so drop the "xfail" marker.
We still have problems with such materialized views, but not in the simple
scenario tested by test_gsi_3.
Later we should create a new test for the scenario which still fails, if
any.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Creating an underlying materialized view with 2 regular base columns
is risky in Scylla, as second's column liveness will not be correctly
taken into account when ensuring view row liveness.
Still, in case specific conditions are met:
* the regular base column value is always present in the base row
* no TTLs are involved
then the materialized view will behave as expected.
Creating a GSI with 2 base regular columns issues a warning,
as it should be performed with care.
Message-Id: <5ce8642c1576529d43ea05e5c4bab64d122df829.1567159633.git.sarna@scylladb.com>
It is important that BillingMode should default to PROVISIONED, as it
does on DynamoDB. This allows old clients, which don't specify
BillingMode at all, to specify ProvisionedThroughput as allowed with
PROVISIONED.
Also added a test case for this case (where BillingMode is absent).
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190829193027.7982-1-nyh@scylladb.com>
When querying on a missing index, DynamoDB returns different errors in
case the entire table is missing (ResourceNotFoundException) or the table
exists and just the index is missing (ValidationException). We didn't
make this distinction, and always returned ValidationException, but this
confuses clients that expect ResourceNotFoundException - e.g., Amazon's
Tic-Tac-Toe demo.
This patch adds a test for the first case (the completely missing table) -
we already had a test for the second case - and returns the correct
error codes. As usual the test passes against DynamoDB as well as Alternator,
ensure they behave the same.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190829174113.5558-1-nyh@scylladb.com>
We needlessly split the trace-level log message for the request to two
messages - one containing just the operation's name, and one with the
parameters. Moreover we printed them in the opposite order (parameters
first, then the operation). So this patch combines them into one log
message.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190829165341.3600-1-nyh@scylladb.com>
Alternator puts in the Scylla table a column called "attrs" for all the
non-key attributes. If the user happens to choose the same name, "attrs",
for one of the key columns, the result of writing two different columns
with the same name is a mess and corrupt sstables.
This test reproduces this bug (and works against DynamoDB of course).
Because the test doesn't cleanly fail, but rather leaves Scylla in a bad
state from which it can't fully recover, the test is marked as "skip"
until we fix this bug.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190828135644.23248-1-nyh@scylladb.com>
Updating key columns is not allowed in UpdateItem requests,
but the series introducing GSI support for regular columns
also introduced redundant duplicates checks of this kind.
This condition is already checked in resolve_update_path helper function
and existing test_update_expression_cannot_modify_key test makes sure that
the condition is checked.
Message-Id: <00f83ab631f93b263003fb09cd7b055bee1565cd.1567086111.git.sarna@scylladb.com>
The test test_update_expression_cannot_modify_key() verifies that an
update expression cannot modify one of the key columns. The existing
test only tried the SET and REMOVE actions - this patch makes the
test more complete by also testing the ADD and DELETE actions.
This patch also makes the expected exception more picky - we now
expect that the exception message contains the word "key" (as it,
indeed, does on both DynamoDB and Alternator). If we get any other
exception, there may be a problem.
The test passed before this patch, and passes now as well - it's just
stricter now.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190829135650.30928-1-nyh@scylladb.com>
Merged patch series from Piotr Sarna:
This miniseries fixes a bug in clustering key deserialization in
alternator and provides a test case for it.
The bug was exposed only if an index (GSI or LSI) was created on a table
with both hash and sort keys defined. The test was checked both locally
and remotely.
Tests: alternator(local, remote)
Piotr Sarna (2):
alternator: use from_single_value instead of from_singular in ck
alternator-test: add test case for GSI with both keys
alternator-test/test_gsi.py | 40 +++++++++++++++++++++++++++++++++++++
alternator/executor.cc | 6 +++---
2 files changed, 43 insertions(+), 3 deletions(-)
The code previously used clustering_key::from_singular() to compute
a clustering key value. It works fine, but has two issues:
1. involves one redundant deserialization stage compared to
from_single_value
2. does not work with compound clustering keys, which can appear
when using indexes
Merged patch series from Piotr Sarna:
This series allows creating Global Secondary Indexes during alternator
table creation. If a regular column is used in the GSI key, it is
included into underlying base table schema together with its type,
as was previously done only for hash and sort keys.
Creating a global index that uses regular base columns for both
hash and sort key is still prohibited, as it's not allowed to create
such materialized views in Scylla and the underlying implementation
of alternator's GSI is based on Scylla's materialized views.
Tests: alternator(local)
Piotr Sarna (8):
alternator: avoid creating empty collection mutations
alternator: start fetching all regular columns
alternator: change attrs column name to :attrs
alternator: add handling regular columns with schema definitions
alternator: allow adding GSI-related regular columns to schema
alternator: add describing GSI in DescribeTable
alternator: Add 'mismatch' to serialization error message
alternator-test: enable passing tests
alternator-test/test_gsi.py | 8 +--
alternator/executor.cc | 120 ++++++++++++++++++++++++++++--------
alternator/executor.hh | 2 +-
alternator/serialization.cc | 2 +-
4 files changed, 99 insertions(+), 33 deletions(-)
With more GSI features implemented, tests with XPASS status are promoted
to being enabled.
One test case (test_gsi_describe) is partially done as DescribeTable
now contains index names, but we could try providing more attributes
(e.g. IndexSizeBytes and ItemCount from the test case), so the test
is left in the XFAIL state.
The DescribeTable request now contains the list of index names
as well. None of the attributes of the list are marked as 'required'
in the documentation, so currently the implementation provides
index names only.
In order to be able to create a Global Secondary Index over a regular
column, this column is upgraded from being a map entry to being a full
member of the schema. As such, it's possible to use this column
definition in the underlying materialized view's key.
In order to prepare alternator for adding regular columns to schema,
i.e. in order to create a materialized view over them,
the code is changed so that updating no longer assumes that only keys
are included in the table schema.
Since in the future we may want to have more regular columns
in alternator tables' schemas, the code is changed accordingly,
so all regular columns will be fetched instead of just the attribute
map.
If no regular column attributes are passed to PutItem, the attr
collector serializes an empty collection mutation nonetheless
and sends it. It's redundant, so instead, if the attr colector
is empty, the collection does not get serialized and sent to replicas.
Keeping an instance of client_state is a convenient way of being able
to use tracing for alternator. It's also currently used in paging,
so adding a client state to executor removes the need of keeping
a dummy value.
String views used in JSON serialization should use not only the pointer
returned by rapidjson, but also the string length, as it may contain
\0 characters.
Additionally, one unnecessary copy is elided.
Add a link to a longer document (currently, around 40 pages) about
DynamoDB's features and how we implemented or may implement them in
Alternator.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190825121201.31747-2-nyh@scylladb.com>
If a user tries to create a table with a unsupported feature -
a local secondary index, a used-defined encryption key or supporting
streams (CDC), let's refuse the table creation, so the application
doesn't continue thinking this feature is available to it.
The "Tags" feature is also not supported, but it is more harmless
(it is used mostly for accounting purposes) so we do not fail the
table creation because of it.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190818125528.9091-1-nyh@scylladb.com>
In CQL, before a user can create a table, they must create a keyspace to
contain this table and, among other things, specify this keyspace's RF.
But in the DynamoDB API, there is no "create keyspace" operation - the
user just creates a table, and there is no way, and no opportunity,
to specify the requested RF. Presumably, Amazon always uses the same
RF for all tables, most likely 3, although this is not officially
documented anywhere.
The existing code creates the keyspace during Scylla boot, with RF=1.
This RF=1 always works, and is a good choice for a one-node test run,
but was a really bad choice for a real cluster with multiple nodes, so
this patch fixes this choice:
With this patch, the keyspace creation is delayed - it doesn't happen
when the first node of the cluster boots, but only when the user creates
the first table. Presumably, at that time, the cluster is already up,
so at that point we can make the obvious choice automatically: a one-node
cluster will get RF=1, a >=3 node cluster will get RF=3. The choice of
RF is logged - and the choice of RF=1 is considered a warning.
Note that with this patch, keyspace creation is still automatic as it
was before. The user may manually create the keyspace via CQL, to
override this automatic choice. In the future we may also add additional
keyspace configuration options via configuration flags or new REST
requests, and the keyspace management code will also likely change
as we start to support clusters with multiple regions and global
tables. But for now, I think the automatic method is easiest for
users who want to test-drive Alternator without reading lengthy
instructions on how to set up the keyspace.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190820180610.5341-1-nyh@scylladb.com>
In the new code, write and read queries take a "service permit" which they
hold for the duration of the query, to help limit the load on the machine.
Alternator doesn't yet participate in this feature, so for now let's just
use empty_service_permit() meaning the queries don't hold on to any permit.
We can fix this later to use real permits.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
We allow BillingMode to be set to either PAY_PER_REQUEST (the default)
or PROVISIONED, although neither mode is fully implemented: In the former
case the payment isn't accounted, and in the latter case the throughput
limits are not enforced.
But other settings for BillingMode are now refused, and we add a new test
to verify that.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190818122919.8431-1-nyh@scylladb.com>
The alternator tests want to exercise many of the DynamoDB API features,
so they need a recent enough version of the client libraries, boto3
and botocore. In particular, only in botocore 1.12.54, released a year
ago, was support for BillingMode added - and we rely on this to create
pay-per-request tables for our tests.
Instead of letting the user run with an old version of this library and
get dozens of mysterious errors, in this patch we add a test to conftest.py
which cleanly aborts the test if the libraries aren't new enough, and
recommends a "pip" command to upgrade these libraries.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190819121831.26101-1-nyh@scylladb.com>
The DescribeTable operation was currently implemented to return the
minimal information that libraries and applications usually need from
it, namely verifying that some table exists. However, this operation
is actually supposed to return a lot more information fields (e.g.,
the size of the table, its creation date, and more) which we currently
don't return.
This patch adds a new test file, test_describe_table.py, testing all
these additional attributes that DescribeTable is supposed to return.
Several of the tests are marked xfail (expected to fail) because we
did not implement these attributes yet.
The test is exhaustive except for attributes that have to do with four
major features which will be tested together with these features: GSI,
LSI, streams (CDC), and backup/restore.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190816132546.2764-1-nyh@scylladb.com>
Currently Alternator starts all Scylla requests (including both reads
and writes) without any timeout set. Because of bugs and/or network
problems, Requests can theoretically hang and waste Scylla request for
hours, long after the client has given up on them and closed their
connection.
The DynamoDB protocol doesn't let a user specify which timeout to use,
so we should just use something "reasonable", in this patch 10 seconds.
Remember that all DynamoDB read and write requests are small (even scans
just scan a small piece), so 10 seconds should be above and beyond
anything we actually expect to see in practice.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190812105132.18651-1-nyh@scylladb.com>
So far we had the "--alternator-port" option allowing to configure the port
on which the Alternator server listens on, but the server always listened
to any address. It is important to also be able to configure the listen
address - it is useful in tests running several instances of Scylla on
the same machine, and useful in multi-homed machines with several interfaces.
So this patch adds the "--alternator-address" option, defaulting to 0.0.0.0
(to listen on all interfaces). It works like the many other "--*-address"
options that Scylla already has.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190808204641.28648-1-nyh@scylladb.com>
It turns out that recent rjson patches introduced some buggy
tabs instead of spaces due to bad IDE configuration. The indentation
is restored to spaces.
Until now, filtering in alternator was possible only for non-key
column equality relations. This commit adds support for equality
relations for key columns.
Alternator allows passing hash and sort key restrictions
as filters - it is, however, better to incorporate these restrictions
directly into partition and clustering ranges, if possible.
It's also necessary, as optimizations inside restrictions_filter
assume that it will not be fed unneeded rows - e.g. if filtering
is not needed on partition key restrictions, they will not be checked.
