Add a size check for BatchItemWrite command - if the item count is
bigger than configuration value `alternator_maximum_batch_write_size`,
an error will be raised and no modification will happen.
This is done to synchronize with DynamoDB, where maximum size of
BatchItemWrite is 25. To avoid complaints from clients, who use
our feature of BatchWriteItem being limitless we set default value
to 100.
Fixes#5057Closesscylladb/scylladb#23232
In commit c24bc3b we decided that creating a new table in Alternator
will by default use vnodes - not tablets - because of all the missing
features in our tablets implementation that are important for
Alternator, namely - LWT, CDC and Alternator TTL.
We never documented this, or the fact that we support a tag
`experimental:initial_tablets` which allows to override this decision
and create an Alternator table using tablets. We also never documented
what exactly doesn't work when Alternator uses tablet.
This patch adds the missing documentation in docs/alternator/new-apis.md
(which is a good place for describing the `experimental:initial_tablets`
tag). The patch also adds a new test file, test_tablets.py, which
includes tests for all the statements made in the document regarding
how `experimental:initial_tablets` works and what works or doesn't
work when tablets are enabled.
Two existing tests - for TTL and Streams non-support with tablets -
are moved to the new test file.
When the tablets feature will finally be completed, both the document
and the tests will need to be modified (some of the tests should be
outright deleted). But it seems this will not happen for at least
several months, and that is too long to wait without accurate
documentation.
Fixes#21629
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#22462
The previous patches implemented issue #11567 - adding a GSI to a
pre-existing table. So we can finally remove the mention of this
feature as an "unimplemented feature" in docs/alternator/compatibility.md.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Two new features were added to DynamoDB this month - MultiRegionConsistency
and WarmThroughput. Document them as unimplemented - and link to the
relevant issue in our bug tracker - in docs/alternator/compatibility.md.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
I reread the "ScyllaDB Alternator for DynamoDB users" document
(alternator/compatibility.md) and improved various places that I thought
needed improvement.
Two of the more significant changes is moving the not-really-important
"Scan ordering" section much lower in the document and explaining it
better, and improving the "provisioning" section to focus on the available
and missing functionality, and not on minor API details.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#21605
In this patch we add to docs/new-apis.md (Alternator-specific API)
a description of the service discovery HTTP requests - `/` and
`/localnodes` that was previously not documented except in a design
document that is unfortunately no longer available publically.
The description also includes the recently added `dc` and `rack`
parameters for the `/localnodes` request.
Fixes#20989
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Before this patch, the documentation of Alternator-specific APIs (APIs
which are unique to Alternator and don't exist in DynamoDB) appear as
a section of the main document alternator.md. In the next patch we
want to describe yet another Alternator feature and make this section
even longer. But there is growing sentiment that the Alternator
documentation should be split into more, shorter, pages (Refs #19822)
so this patch splits the Alternator-specific API documentation into a
new file, new-apis.md.
There is no new content in the patch - just movement of existing content
plus a reference to the new page.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
When users create a table using the Alternator API, they can decide if the billing is PROVISIONED of PAY_PER_REQUEST.
If the billing is set to PROVISIONED, they need to set the ProvisionedThroughput ReadCapacityUnits (RCU) and WriteCapacityUnits (WCU).
This series adds support for getting and setting the ProvisionedThroughput. The values will be stored as table extension tags.
Following how TTL is stored within the Alternator, we will use ```system:rcu_attribute``` and ```system:wcu_attribute``` for the labels.
The series adds a test that sets ProvisionedThroughput and validates that it gets the value back. It was tested with both Alternator and AWS.
This series is part of the effort to monitor, limit, and bill Alternator operations.
New code, no need to backport.
Closesscylladb/scylladb#20056
* github.com:scylladb/scylladb:
docs/alternator/compatibility.md: explain the consumed capacity provisioned
Add test/alternator/test_provisioned_throughput.py
test/alternator/util.py: Allow override BillingMode
alternator/executor.cc: Store ProvisionedThroughput
This commit hides the ToC, as we don't need it, especially at the end of the page.
The ToC must be hidden rather than removed because removing it would, in turn,
remove the "Getting Started With ScyllaDB Alternator" and "ScyllaDB Alternator for DynamoDB users"
from the page tree and make them inaccessible.
This patch change the alternator documentation to express that the
provisoned units are stored and return but Alternator ignores them.
Signed-off-by: Amnon Heiman <amnon@scylladb.com>
In docs/alternator/compatibility.md we said that although Alternator
supports authentication, it doesn't support authorization (access
control). Now it does, so the relevant text needs to be corrected
to fit what we have today.
It's still in the compatibility.md document because it's not the same
API as DynamoDB's, so users with existing applications may need to be
aware of this difference.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
This commit removes the 5.4-to-6.0 upgrade guide and all references to it.
It mainly removes references to the Enable Consistent Topology Updates page,
which was added as enabling the feature was optional.
In rare cases, when a reference to that page is necessary,
the internal link is replaced with an external link to version 6.0.
Especially the Handling Cluster Membership Change Failures page was modified
for troubleshooting purposes rather than removed.
There's already a page which lists which features are not working with
tablets: architecture/tablets.html#limitations-and-unsupported-features,
but it's also helpful for users to be warned about this when visiting a
specific feature doc page.
Separate keyspace which also behaves as system brings
little benefit while creating some compatibility problems
like schema digest mismatch during rollback. So we decided
to move auth tables into system keyspace.
Fixes https://github.com/scylladb/scylladb/issues/18098Closesscylladb/scylladb#18769
This commit includes updates related to replacing system_auth with system_auth_v2.
- The keyspace name system_auth is renamed to system_auth_v2.
- The procedures are updated to account for system_auth_v2.
- No longer required system_auth RF changes are removed from procedures.
- The information is added that if the consistent topology updates feature
was not enabled upon upgrade from 5.4, there are limitations or additional
steps to do (depending on the procedure).
The files with that kind of information are to be found in _common folders
and included as needed.
- The upgrade guide has been updated to reflect system_auth_v2 and related impacts.
Closesscylladb/scylladb#18077
This patch adds to docs/alternator/compatibility.md mentions of three
recently-added DynamoDB features (ReturnValuesOnConditionCheckFailure,
DeletionProtectionEnabled and TableClass) which Alternator does not yet
support.
Each of these mentions also links to the github issue we have on each
feature - issues #14481, #14482 and #10431 respectively.
During a review of this patch, the reviewers didn't like that I used
words like "recent" and "new" to describe recently-added DynamoDB
features, and asked that I use specific dates instead. So this is what
I do in this patch for the new features - and I also went back and
fixed a few pre-existing references to "recent" and "new" features,
and added the dates.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#14483
In issue #5283 we noted that the auto_snapshot option is not useful
in Alternator (as we don't offer any API to restore the snapshot...),
and suggested that we should automatically disable this option for
Alternator tables. However, this issue has been open for more than three
years, and we never changed this default.
So until we solve that issue - if we ever do - let's add a paragraph
in docs/alternator/alternator.md recommending to the user to disable
this option in the configuration themselves. The text explains why,
and also provides a link to the issue.
Refs #5283
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#13103
docs/alternator/compatibility.md mentions a known problem that
Alternator Streams are divided into too many "shards". This patch
add a link to a github issue to track our work on this issue - like
we did for most other differences mentioned in compatibility.md.
Refs #13080
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#13081
This PR adds a note to the Alternator TTL section to specify in which Open Source and Enterprise versions the feature was promoted from experimental to non-experimental.
The challenge here is that OSS and Enterprise are (still) **documented together**, but they're **not in sync** in promoting the TTL feature: it's still experimental in 5.1 (released) but no longer experimental in 2022.2 (to be released soon).
We can take one of the following approaches:
a) Merge this PR with master and ask the 2022.2 users to refer to master.
b) Merge this PR with master and then backport to branch-5.1. If we choose this approach, it is necessary to backport https://github.com/scylladb/scylladb/pull/11997 beforehand to avoid conflicts.
I'd opt for a) because it makes more sense from the OSS perspective and helps us avoid mess and backporting.
Closes#12295
* github.com:scylladb/scylladb:
doc: fix the version in the comment on removing the note
doc: specify the versions where Alternator TTL is no longer experimental
The docs/alternator/compatibility.md file links to various open issues
on unimplemented features. One of the links was to an already-closed
issue. Replace it by a link to an open issue that was missing.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12649
The alternator compatibility.md document mentions the missing ACL
(access control) feature, but unlike other missing features we
forgot to link to the open issue about this missing feature.
So let's add that link.
Refs #5047.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12399
In August 2022, DynamoDB added a "S3 Import" feature, which we don't yet
support - so let's document this missing feature in the compatibility
document.
Refs #11739.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11740
Update several aspects of the alternator/getting-started.md which were
not up-to-date:
* When the documented was written, Alternator was moving quickly so we
recommended running a nightly version. This is no longer the case, so
we should recommend running the latest stable build.
* The link to the download link is no longer helpful for getting Docker
instructions (it shows some generic download options). Instead point to
our dockerhub page.
* Replace mentions of "Scylla" by the new official name, "ScyllaDB".
* Miscelleneous copy-edits.
Fixes#11218
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11605
In compatibility.md where we refer to the missing ability to add a GSI
to an existing table - let's refer to a new issue specifically about this
feature, instead of the old bigger issue about UpdateItem.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11568
The directory that used to be called alternator-test is now (and has
been for a long time) really test/alternator. So let's fix the
references to it in docs/alternator/alternator.md.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
This commit introduces the following changes to Alternator compability doc:
* As of https://github.com/scylladb/scylladb/pull/11298 Alternator will return ProvisionedThroughput in DescribeTable API calls. We add the fact that tables will default to a BillingMode of PAY_PER_REQUEST (this wasn't made explicit anywhere in the docs), and that the values for RCUs/WCUs are hardcoded to 0.
* Mention the fact that ScyllaDB (thus Alternator) hashing function is different than AWS proprietary implementation for DynamoDB. This is mostly of an implementation aspect rather than a bug, but it may cause user confusion when/if comparing the ResultSet between DynamoDB and Alternator returned from Table Scans.
Refs: https://github.com/scylladb/scylladb/issues/11222
Fixes: https://github.com/scylladb/scylladb/issues/11315Closes#11360
In issue #10966, a user noticed that Alternator writes may be reordered
(a later write to an item is ignored with the earlier write to the same
item "winning") if Scylla nodes do not have synchronized time and if
always_use_lwt write isolation mode is not used.
In this patch I add to docs/alternator/compatibility.md a section about
this issue, what causes it, and how to solve or at least mitigate it.
Fixes#10966
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11094
Currently in docs/alternator/compatibility.md experimental features
and unimplemented features are bunched together under one heading
("unimplemented features"). In this patch we separate them into two
sections. This makes the "unimplemented features" section shorter,
and also allows us to link to the new "experimental features" section
separately.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#10893
This patch implements the previously-unimplemented Select option of the
Query and Scan operators.
The most interesting use case of this option is Select=COUNT which means
we should only count the items, without returning their actual content.
But there are actually four different Select settings: COUNT,
ALL_ATTRIBUTES, SPECIFIC_ATTRIBUTES, and ALL_PROJECTED_ATTRIBUTES.
Five previously-failing tests now pass, and their xfail mark is removed:
* test_query.py::test_query_select
* test_scan.py::test_scan_select
* test_query_filter.py::test_query_filter_and_select_count
* test_filter_expression.py::test_filter_expression_and_select_count
* test_gsi.py::test_gsi_query_select_1
These tests cover many different cases of successes and errors, including
combination of Select and other options. E.g., combining Select=COUNT
with filtering requires us to get the parts of the items needed for the
filtering function - even if we don't need to return them to the user
at the end.
Because we do not yet support GSI/LSI projection (issue #5036), the
support for ALL_PROJECTED_ATTRIBUTES is a bit simpler than it will need
to be in the future, but we can only finish that after #5036 is done.
Fixes#5058.
The most intrusive part of this patch is a change from attrs_to_get -
a map of top-level attributes that a read needs to fetch - to an
optional<attrs_to_get>. This change is needed because we also need
to support the case that we want to read no attributes (Select=COUNT),
and attrs_to_get.empty() used to mean that we want to read *all*
attributes, not no attributes. After this patch, an unset
optional<attrs_to_get> means read *all* attributes, a set but empty
attrs_to_get means read *no* attributes, and a set and non-empty
attrs_to_get means read those specific attributes.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20220405113700.9768-2-nyh@scylladb.com>
The document docs/alternator/compatibility.md suggested that Alternator
does not support the TTL feature at all. The real situation is more
optimistic - this feature is supported, but as experimental feature.
So let's update compatibility.md with the real status of this feature.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Now that issues #7586 and #9487 were fixed, reverse queries - even in
long partitions - work well, we can drop the claim in
alternator/docs/compatibility.md that reverse queries are buggy for
large partitions.
We can also remove the "xfail" mark from the tes that checks this
feature, as it now passes.
Refs #7586
Refs #9487
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#9831
