542b2ed0de
The class was introduced to facilitate path and query parameters parsing from requests, but in fact it's mostly dead code. First, the class introduces the concept of "mandatory" parameters which are seastar path params. If missing, the parameter validation throws, but in all cases where this option is used in scylla it's impossible to get empty path param -- if the parameter is missing seastar returns 404 (not found) before calling handler. Second, the req_params::get<T>() doesn't work for anything but string argument (or types such that optional<T> can be implicitly casted to optional<sstring>). And it's in fact only used to get sstrings, so it compiles and works so far. The remaining ability to parse bool from string is partially duplicated by the validate_bool() method. Using plain method to parse string to bool is less code than req_params introduce. One (arguably) useful thing req_params do it validate the incoming request _not_ to contain unknown query parameters. However, quite a few endpoints use this, most of them just cherry-pick parameters they want and ignore the others. There's already a comprehensive description of accepted parameters for each endpoint in api-doc/ and req_params duplicate it. Good validation code should rely on api-doc/, not on its partial copy. Having said that, this PR introduces validate_bool_x() helper to do req_params-like parsing of strings to bools, patches existing handlers to use existing parameters parsing facilities (such as validate_keyspace() and parse_table_infos()) and drops the req_params. Closes scylladb/scylladb#24159 * github.com:scylladb/scylladb: api: Drop class req_params api: Stop using req_params in parse_scrub_options api: Stop using req_params in tasks::force_keyspace_compaction_async api: Stop using req_params in ss::force_keyspace_compaction api: Stop using req_params in ss::force_compaction api: Stop using req_params in cf::force_major_compaction api: Add validate_bool_x() helper
Scylla
What is Scylla?
Scylla is the real-time big data database that is API-compatible with Apache Cassandra and Amazon DynamoDB. Scylla embraces a shared-nothing approach that increases throughput and storage capacity to realize order-of-magnitude performance improvements and reduce hardware costs.
For more information, please see the ScyllaDB web site.
Build Prerequisites
Scylla is fairly fussy about its build environment, requiring very recent versions of the C++23 compiler and of many libraries to build. The document HACKING.md includes detailed information on building and developing Scylla, but to get Scylla building quickly on (almost) any build machine, Scylla offers a frozen toolchain, This is a pre-configured Docker image which includes recent versions of all the required compilers, libraries and build tools. Using the frozen toolchain allows you to avoid changing anything in your build machine to meet Scylla's requirements - you just need to meet the frozen toolchain's prerequisites (mostly, Docker or Podman being available).
Building Scylla
Building Scylla with the frozen toolchain dbuild is as easy as:
$ git submodule update --init --force --recursive
$ ./tools/toolchain/dbuild ./configure.py
$ ./tools/toolchain/dbuild ninja build/release/scylla
For further information, please see:
- Developer documentation for more information on building Scylla.
- Build documentation on how to build Scylla binaries, tests, and packages.
- Docker image build documentation for information on how to build Docker images.
Running Scylla
To start Scylla server, run:
$ ./tools/toolchain/dbuild ./build/release/scylla --workdir tmp --smp 1 --developer-mode 1
This will start a Scylla node with one CPU core allocated to it and data files stored in the tmp directory.
The --developer-mode is needed to disable the various checks Scylla performs at startup to ensure the machine is configured for maximum performance (not relevant on development workstations).
Please note that you need to run Scylla with dbuild if you built it with the frozen toolchain.
For more run options, run:
$ ./tools/toolchain/dbuild ./build/release/scylla --help
Testing
See test.py manual.
Scylla APIs and compatibility
By default, Scylla is compatible with Apache Cassandra and its API - CQL. There is also support for the API of Amazon DynamoDB™, which needs to be enabled and configured in order to be used. For more information on how to enable the DynamoDB™ API in Scylla, and the current compatibility of this feature as well as Scylla-specific extensions, see Alternator and Getting started with Alternator.
Documentation
Documentation can be found here. Seastar documentation can be found here. User documentation can be found here.
Training
Training material and online courses can be found at Scylla University. The courses are free, self-paced and include hands-on examples. They cover a variety of topics including Scylla data modeling, administration, architecture, basic NoSQL concepts, using drivers for application development, Scylla setup, failover, compactions, multi-datacenters and how Scylla integrates with third-party applications.
Contributing to Scylla
If you want to report a bug or submit a pull request or a patch, please read the contribution guidelines.
If you are a developer working on Scylla, please read the developer guidelines.
Contact
- The community forum and Slack channel are for users to discuss configuration, management, and operations of ScyllaDB.
- The developers mailing list is for developers and people interested in following the development of ScyllaDB to discuss technical topics.