Files
scylla/db/legacy_schema_migrator.cc
Yaniv Kaul c658bdb150 Typos: fix typos in comments
Fixes some typos as found by codespell run on the code.
In this commit, I was hoping to fix only comments, not user-visible alerts, output, etc.
Follow-up commits will take care of them.

Refs: https://github.com/scylladb/scylladb/issues/16255
Signed-off-by: Yaniv Kaul <yaniv.kaul@scylladb.com>
2023-12-02 22:37:22 +02:00

608 lines
28 KiB
C++

/*
* Modified by ScyllaDB
* Copyright (C) 2017-present ScyllaDB
*/
/*
* SPDX-License-Identifier: (AGPL-3.0-or-later and Apache-2.0)
*/
// Since Scylla 2.0, we use system tables whose schemas were introduced in
// Cassandra 3. If Scylla boots to find a data directory with system tables
// with older schemas - produced by pre-2.0 Scylla or by pre-3.0 Cassandra,
// we need to migrate these old tables to the new format.
//
// We provide here a function, db::legacy_schema_migrator::migrate(),
// for a one-time migration from old to new system tables. The function
// reads old system tables, write them back in the new format, and finally
// delete the old system tables. Scylla's main should call this function and
// wait for the returned future, before starting to serve the database.
#include <boost/iterator/filter_iterator.hpp>
#include <seastar/core/future-util.hh>
#include <seastar/util/log.hh>
#include <map>
#include <unordered_set>
#include <chrono>
#include "replica/database.hh"
#include "legacy_schema_migrator.hh"
#include "system_keyspace.hh"
#include "schema_tables.hh"
#include "schema/schema_builder.hh"
#include "service/storage_proxy.hh"
#include "utils/rjson.hh"
#include "utils/fmt-compat.hh"
#include "cql3/query_processor.hh"
#include "cql3/untyped_result_set.hh"
#include "cql3/util.hh"
#include "types/user.hh"
static seastar::logger mlogger("legacy_schema_migrator");
namespace db {
namespace legacy_schema_migrator {
// local data carriers
class migrator {
public:
static const std::unordered_set<sstring> legacy_schema_tables;
migrator(sharded<service::storage_proxy>& sp, sharded<replica::database>& db, sharded<db::system_keyspace>& sys_ks, cql3::query_processor& qp)
: _sp(sp), _db(db), _sys_ks(sys_ks), _qp(qp) {
}
migrator(migrator&&) = default;
typedef db_clock::time_point time_point;
// TODO: we don't support triggers.
// this is a placeholder.
struct trigger {
time_point timestamp;
sstring name;
std::unordered_map<sstring, sstring> options;
};
struct table {
time_point timestamp;
schema_ptr metadata;
std::vector<trigger> triggers;
};
struct type {
time_point timestamp;
user_type metadata;
};
struct function {
time_point timestamp;
sstring ks_name;
sstring fn_name;
std::vector<sstring> arg_names;
std::vector<sstring> arg_types;
sstring return_type;
bool called_on_null_input;
sstring language;
sstring body;
};
struct aggregate {
time_point timestamp;
sstring ks_name;
sstring fn_name;
std::vector<sstring> arg_names;
std::vector<sstring> arg_types;
sstring return_type;
sstring final_func;
sstring initcond;
sstring state_func;
sstring state_type;
};
struct keyspace {
time_point timestamp;
sstring name;
bool durable_writes;
std::map<sstring, sstring> replication_params;
std::vector<table> tables;
std::vector<type> types;
std::vector<function> functions;
std::vector<aggregate> aggregates;
};
class unsupported_feature : public std::runtime_error {
public:
using runtime_error::runtime_error;
};
static sstring fmt_query(const char* fmt, const char* table) {
return fmt::format(fmt::runtime(fmt), db::system_keyspace::NAME, table);
}
typedef ::shared_ptr<cql3::untyped_result_set> result_set_type;
typedef const cql3::untyped_result_set::row row_type;
future<> read_table(keyspace& dst, sstring cf_name, time_point timestamp) {
auto fmt = "SELECT * FROM {}.{} WHERE keyspace_name = ? AND columnfamily_name = ?";
auto tq = fmt_query(fmt, db::system_keyspace::legacy::COLUMNFAMILIES);
auto cq = fmt_query(fmt, db::system_keyspace::legacy::COLUMNS);
auto zq = fmt_query(fmt, db::system_keyspace::legacy::TRIGGERS);
typedef std::tuple<future<result_set_type>, future<result_set_type>, future<result_set_type>, future<db::schema_tables::legacy::schema_mutations>> result_tuple;
return when_all(_qp.execute_internal(tq, { dst.name, cf_name }, cql3::query_processor::cache_internal::yes),
_qp.execute_internal(cq, { dst.name, cf_name }, cql3::query_processor::cache_internal::yes),
_qp.execute_internal(zq, { dst.name, cf_name }, cql3::query_processor::cache_internal::yes),
db::schema_tables::legacy::read_table_mutations(_sp, dst.name, cf_name, db::system_keyspace::legacy::column_families()))
.then([&dst, cf_name, timestamp](result_tuple&& t) {
result_set_type tables = std::get<0>(t).get0();
result_set_type columns = std::get<1>(t).get0();
result_set_type triggers = std::get<2>(t).get0();
db::schema_tables::legacy::schema_mutations sm = std::get<3>(t).get0();
row_type& td = tables->one();
auto ks_name = td.get_as<sstring>("keyspace_name");
auto cf_name = td.get_as<sstring>("columnfamily_name");
auto id = table_id(td.get_or("cf_id", generate_legacy_id(ks_name, cf_name).uuid()));
schema_builder builder(dst.name, cf_name, id);
builder.with_version(sm.digest());
cf_type cf = sstring_to_cf_type(td.get_or("type", sstring("standard")));
if (cf == cf_type::super) {
fail(unimplemented::cause::SUPER);
}
auto comparator = td.get_as<sstring>("comparator");
bool is_compound = cell_comparator::check_compound(comparator);
builder.set_is_compound(is_compound);
cell_comparator::read_collections(builder, comparator);
bool filter_sparse = false;
data_type default_validator = {};
if (td.has("default_validator")) {
default_validator = db::schema_tables::parse_type(td.get_as<sstring>("default_validator"));
if (default_validator->is_counter()) {
builder.set_is_counter(true);
}
builder.set_default_validation_class(default_validator);
}
/*
* Determine whether or not the table is *really* dense
* We cannot trust is_dense value of true (see CASSANDRA-11502, that fixed the issue for 2.2 only, and not retroactively),
* but we can trust is_dense value of false.
*/
auto is_dense = td.get_opt<bool>("is_dense");
if (!is_dense || *is_dense) {
is_dense = [&] {
/*
* As said above, this method is only here because we need to deal with thrift upgrades.
* Once a CF has been "upgraded", i.e. we've rebuilt and save its CQL3 metadata at least once,
* then we'll have saved the "is_dense" value and will be good to go.
*
* But non-upgraded thrift CF (and pre-7744 CF) will have no value for "is_dense", so we need
* to infer that information without relying on it in that case. And for the most part this is
* easy, a CF that has at least one REGULAR definition is not dense. But the subtlety is that not
* having a REGULAR definition may not mean dense because of CQL3 definitions that have only the
* PRIMARY KEY defined.
*
* So we need to recognize those special case CQL3 table with only a primary key. If we have some
* clustering columns, we're fine as said above. So the only problem is that we cannot decide for
* sure if a CF without REGULAR columns nor CLUSTERING_COLUMN definition is meant to be dense, or if it
* has been created in CQL3 by say:
* CREATE TABLE test (k int PRIMARY KEY)
* in which case it should not be dense. However, we can limit our margin of error by assuming we are
* in the latter case only if the comparator is exactly CompositeType(UTF8Type).
*/
std::optional<column_id> max_cl_idx;
const cql3::untyped_result_set::row * regular = nullptr;
for (auto& row : *columns) {
auto kind_str = row.get_as<sstring>("type");
if (kind_str == "compact_value") {
continue;
}
auto kind = db::schema_tables::deserialize_kind(kind_str);
if (kind == column_kind::regular_column) {
if (regular != nullptr) {
return false;
}
regular = &row;
continue;
}
if (kind == column_kind::clustering_key) {
max_cl_idx = std::max(column_id(row.get_or("component_index", 0)), max_cl_idx.value_or(column_id()));
}
}
auto is_cql3_only_pk_comparator = [](const sstring& comparator) {
if (!cell_comparator::check_compound(comparator)) {
return false;
}
// CMH. We don't have composites, nor a parser for it. This is a simple way of c
// checking the same.
auto comma = comparator.find(',');
if (comma != sstring::npos) {
return false;
}
auto off = comparator.find('(');
auto end = comparator.find(')');
return comparator.compare(off, end - off, utf8_type->name()) == 0;
};
if (max_cl_idx) {
auto n = std::count(comparator.begin(), comparator.end(), ','); // num comp - 1
return *max_cl_idx == n;
}
if (regular) {
return false;
}
return !is_cql3_only_pk_comparator(comparator);
}();
// now, if switched to sparse, remove redundant compact_value column and the last clustering column,
// directly copying CASSANDRA-11502 logic. See CASSANDRA-11315.
filter_sparse = !*is_dense;
}
builder.set_is_dense(*is_dense);
auto is_cql = !*is_dense && is_compound;
auto is_static_compact = !*is_dense && !is_compound;
// org.apache.cassandra.schema.LegacySchemaMigrator#isEmptyCompactValueColumn
auto is_empty_compact_value = [](const cql3::untyped_result_set::row& column_row) {
auto kind_str = column_row.get_as<sstring>("type");
// Cassandra only checks for "compact_value", but Scylla generates "regular" instead (#2586)
return (kind_str == "compact_value" || kind_str == "regular")
&& column_row.get_as<sstring>("column_name").empty();
};
for (auto& row : *columns) {
auto kind_str = row.get_as<sstring>("type");
auto kind = db::schema_tables::deserialize_kind(kind_str);
auto component_index = kind > column_kind::clustering_key ? 0 : column_id(row.get_or("component_index", 0));
auto name = row.get_or<sstring>("column_name", sstring());
auto validator = db::schema_tables::parse_type(row.get_as<sstring>("validator"));
if (is_empty_compact_value(row)) {
continue;
}
if (filter_sparse) {
if (kind_str == "compact_value") {
continue;
}
if (kind == column_kind::clustering_key) {
if (cf == cf_type::super && component_index != 0) {
continue;
}
if (cf != cf_type::super && !is_compound) {
continue;
}
}
}
std::optional<index_metadata_kind> index_kind;
sstring index_name;
index_options_map options;
if (row.has("index_type")) {
index_kind = schema_tables::deserialize_index_kind(row.get_as<sstring>("index_type"));
}
if (row.has("index_name")) {
index_name = row.get_as<sstring>("index_name");
}
if (row.has("index_options")) {
sstring index_options_str = row.get_as<sstring>("index_options");
options = rjson::parse_to_map<index_options_map>(std::string_view(index_options_str));
sstring type;
auto i = options.find("index_keys");
if (i != options.end()) {
options.erase(i);
type = "KEYS";
}
i = options.find("index_keys_and_values");
if (i != options.end()) {
options.erase(i);
type = "KEYS_AND_VALUES";
}
if (type.empty()) {
if (validator->is_collection() && validator->is_multi_cell()) {
type = "FULL";
} else {
type = "VALUES";
}
}
auto column = cql3::util::maybe_quote(name);
options["target"] = validator->is_collection()
? type + "(" + column + ")"
: column;
}
if (index_kind) {
// Origin assumes index_name is always set, so let's do the same
builder.with_index(index_metadata(index_name, options, *index_kind, index_metadata::is_local_index::no));
}
data_type column_name_type = [&] {
if (is_static_compact && kind == column_kind::regular_column) {
return db::schema_tables::parse_type(comparator);
}
return utf8_type;
}();
auto column_name = [&] {
try {
return column_name_type->from_string(name);
} catch (marshal_exception&) {
// #2597: Scylla < 2.0 writes names in serialized form, try to recover
column_name_type->validate(to_bytes_view(name));
return to_bytes(name);
}
}();
builder.with_column_ordered(column_definition(std::move(column_name), std::move(validator), kind, component_index));
}
if (is_static_compact) {
builder.set_regular_column_name_type(db::schema_tables::parse_type(comparator));
}
if (td.has("read_repair_chance")) {
builder.set_read_repair_chance(td.get_as<double>("read_repair_chance"));
}
if (td.has("local_read_repair_chance")) {
builder.set_dc_local_read_repair_chance(td.get_as<double>("local_read_repair_chance"));
}
if (td.has("gc_grace_seconds")) {
builder.set_gc_grace_seconds(td.get_as<int32_t>("gc_grace_seconds"));
}
if (td.has("min_compaction_threshold")) {
builder.set_min_compaction_threshold(td.get_as<int32_t>("min_compaction_threshold"));
}
if (td.has("max_compaction_threshold")) {
builder.set_max_compaction_threshold(td.get_as<int32_t>("max_compaction_threshold"));
}
if (td.has("comment")) {
builder.set_comment(td.get_as<sstring>("comment"));
}
if (td.has("memtable_flush_period_in_ms")) {
builder.set_memtable_flush_period(td.get_as<int32_t>("memtable_flush_period_in_ms"));
}
if (td.has("caching")) {
builder.set_caching_options(caching_options::from_sstring(td.get_as<sstring>("caching")));
}
if (td.has("default_time_to_live")) {
builder.set_default_time_to_live(gc_clock::duration(td.get_as<int32_t>("default_time_to_live")));
}
if (td.has("speculative_retry")) {
builder.set_speculative_retry(td.get_as<sstring>("speculative_retry"));
}
if (td.has("compaction_strategy_class")) {
auto strategy = td.get_as<sstring>("compaction_strategy_class");
try {
builder.set_compaction_strategy(sstables::compaction_strategy::type(strategy));
} catch (const exceptions::configuration_exception& e) {
// If compaction strategy class isn't supported, fallback to size tiered.
mlogger.warn("Falling back to size-tiered compaction strategy after the problem: {}", e.what());
builder.set_compaction_strategy(sstables::compaction_strategy_type::size_tiered);
}
}
if (td.has("compaction_strategy_options")) {
sstring strategy_options_str = td.get_as<sstring>("compaction_strategy_options");
builder.set_compaction_strategy_options(rjson::parse_to_map<std::map<sstring, sstring>>(std::string_view(strategy_options_str)));
}
auto comp_param = td.get_as<sstring>("compression_parameters");
compression_parameters cp(rjson::parse_to_map<std::map<sstring, sstring>>(std::string_view(comp_param)));
builder.set_compressor_params(cp);
if (td.has("min_index_interval")) {
builder.set_min_index_interval(td.get_as<int32_t>("min_index_interval"));
} else if (td.has("index_interval")) { // compatibility
builder.set_min_index_interval(td.get_as<int32_t>("index_interval"));
}
if (td.has("max_index_interval")) {
builder.set_max_index_interval(td.get_as<int32_t>("max_index_interval"));
}
if (td.has("bloom_filter_fp_chance")) {
builder.set_bloom_filter_fp_chance(td.get_as<double>("bloom_filter_fp_chance"));
} else {
builder.set_bloom_filter_fp_chance(builder.get_bloom_filter_fp_chance());
}
if (td.has("dropped_columns")) {
auto map = td.get_map<sstring, int64_t>("dropped_columns");
for (auto&& e : map) {
builder.without_column(e.first, api::timestamp_type(e.second));
};
}
// ignore version. we're transient
if (!triggers->empty()) {
throw unsupported_feature("triggers");
}
dst.tables.emplace_back(table{timestamp, builder.build() });
});
}
future<> read_tables(keyspace& dst) {
auto query = fmt_query("SELECT columnfamily_name, writeTime(type) AS timestamp FROM {}.{} WHERE keyspace_name = ?",
db::system_keyspace::legacy::COLUMNFAMILIES);
return _qp.execute_internal(query, {dst.name}, cql3::query_processor::cache_internal::yes).then([this, &dst](result_set_type result) {
return parallel_for_each(*result, [this, &dst](row_type& row) {
return read_table(dst, row.get_as<sstring>("columnfamily_name"), row.get_as<time_point>("timestamp"));
}).finally([result] {});
});
}
future<time_point> read_type_timestamp(keyspace& dst, sstring type_name) {
// TODO: Unfortunately there is not a single REGULAR column in system.schema_usertypes, so annoyingly we cannot
// use the writeTime() CQL function, and must resort to a lower level.
// Origin digs up the actual cells of target partition and gets timestamp from there.
// We should do the same, but g-dam that's messy. Lets give back dung value for now.
return make_ready_future<time_point>(dst.timestamp);
}
future<> read_types(keyspace& dst) {
auto query = fmt_query("SELECT * FROM {}.{} WHERE keyspace_name = ?", db::system_keyspace::legacy::USERTYPES);
return _qp.execute_internal(query, {dst.name}, cql3::query_processor::cache_internal::yes).then([this, &dst](result_set_type result) {
return parallel_for_each(*result, [this, &dst](row_type& row) {
auto name = row.get_blob("type_name");
auto columns = row.get_list<bytes>("field_names");
auto types = row.get_list<sstring>("field_types");
std::vector<data_type> field_types;
for (auto&& value : types) {
field_types.emplace_back(db::schema_tables::parse_type(value));
}
auto ut = user_type_impl::get_instance(dst.name, name, columns, field_types, false);
return read_type_timestamp(dst, value_cast<sstring>(utf8_type->deserialize(name))).then([ut = std::move(ut), &dst](time_point timestamp) {
dst.types.emplace_back(type{timestamp, ut});
});
}).finally([result] {});
});
}
future<> read_functions(keyspace& dst) {
auto query = fmt_query("SELECT * FROM {}.{} WHERE keyspace_name = ?", db::system_keyspace::legacy::FUNCTIONS);
return _qp.execute_internal(query, {dst.name}, cql3::query_processor::cache_internal::yes).then([](result_set_type result) {
if (!result->empty()) {
throw unsupported_feature("functions");
}
});
}
future<> read_aggregates(keyspace& dst) {
auto query = fmt_query("SELECT * FROM {}.{} WHERE keyspace_name = ?", db::system_keyspace::legacy::AGGREGATES);
return _qp.execute_internal(query, {dst.name}, cql3::query_processor::cache_internal::yes).then([](result_set_type result) {
if (!result->empty()) {
throw unsupported_feature("aggregates");
}
});
}
future<keyspace> read_keyspace(sstring ks_name, bool durable_writes, sstring strategy_class, sstring strategy_options, time_point timestamp) {
auto map = rjson::parse_to_map<std::map<sstring, sstring>>(std::string_view(strategy_options));
map.emplace("class", std::move(strategy_class));
auto ks = ::make_lw_shared<keyspace>(keyspace{timestamp, std::move(ks_name), durable_writes, std::move(map) });
return read_tables(*ks).then([this, ks] {
//Collection<Type> types = readTypes(keyspaceName);
return read_types(*ks);
}).then([this, ks] {
return read_functions(*ks);
}).then([this, ks] {
return read_aggregates(*ks);
}).then([ks] {
return make_ready_future<keyspace>(std::move(*ks));
});
}
future<> read_all_keyspaces() {
static auto ks_filter = [](row_type& row) {
auto ks_name = row.get_as<sstring>("keyspace_name");
return ks_name != db::system_keyspace::NAME && ks_name != db::schema_tables::v3::NAME;
};
auto query = fmt_query("SELECT keyspace_name, durable_writes, strategy_options, strategy_class, writeTime(durable_writes) AS timestamp FROM {}.{}",
db::system_keyspace::legacy::KEYSPACES);
return _qp.execute_internal(query, cql3::query_processor::cache_internal::yes).then([this](result_set_type result) {
auto i = boost::make_filter_iterator(ks_filter, result->begin(), result->end());
auto e = boost::make_filter_iterator(ks_filter, result->end(), result->end());
return parallel_for_each(i, e, [this](row_type& row) {
return read_keyspace(row.get_as<sstring>("keyspace_name")
, row.get_as<bool>("durable_writes")
, row.get_as<sstring>("strategy_class")
, row.get_as<sstring>("strategy_options")
, row.get_as<db_clock::time_point>("timestamp")
).then([this](keyspace ks) {
_keyspaces.emplace_back(std::move(ks));
});
}).finally([result] {});
});
}
future<> drop_legacy_tables() {
mlogger.info("Dropping legacy schema tables");
auto with_snapshot = !_keyspaces.empty();
return parallel_for_each(legacy_schema_tables, [this, with_snapshot](const sstring& cfname) {
return replica::database::drop_table_on_all_shards(_db, _sys_ks, db::system_keyspace::NAME, cfname, with_snapshot);
});
}
future<> store_keyspaces_in_new_schema_tables() {
mlogger.info("Moving {} keyspaces from legacy schema tables to the new schema keyspace ({})",
_keyspaces.size(), db::schema_tables::v3::NAME);
std::vector<mutation> mutations;
for (auto& ks : _keyspaces) {
auto ksm = ::make_lw_shared<keyspace_metadata>(ks.name
, ks.replication_params["class"] // TODO, make ksm like c3?
, ks.replication_params
, ks.durable_writes);
// we want separate time stamps for tables/types, so cannot bulk them into the ksm.
for (auto&& m : db::schema_tables::make_create_keyspace_mutations(schema_features::full(), ksm, ks.timestamp.time_since_epoch().count(), false)) {
mutations.emplace_back(std::move(m));
}
for (auto& t : ks.tables) {
db::schema_tables::add_table_or_view_to_schema_mutation(t.metadata, t.timestamp.time_since_epoch().count(), true, mutations);
}
for (auto& t : ks.types) {
db::schema_tables::add_type_to_schema_mutation(t.metadata, t.timestamp.time_since_epoch().count(), mutations);
}
}
return _qp.proxy().mutate_locally(std::move(mutations), tracing::trace_state_ptr());
}
future<> flush_schemas() {
auto& db = _qp.db().real_database().container();
return replica::database::flush_tables_on_all_shards(db, db::schema_tables::NAME, db::schema_tables::all_table_names(schema_features::full()));
}
future<> migrate() {
return read_all_keyspaces().then([this]() {
// write metadata to the new schema tables
return store_keyspaces_in_new_schema_tables()
.then(std::bind(&migrator::flush_schemas, this))
.then(std::bind(&migrator::drop_legacy_tables, this))
.then([] { mlogger.info("Completed migration of legacy schema tables"); });
});
}
sharded<service::storage_proxy>& _sp;
sharded<replica::database>& _db;
sharded<db::system_keyspace>& _sys_ks;
cql3::query_processor& _qp;
std::vector<keyspace> _keyspaces;
};
const std::unordered_set<sstring> migrator::legacy_schema_tables = {
db::system_keyspace::legacy::KEYSPACES,
db::system_keyspace::legacy::COLUMNFAMILIES,
db::system_keyspace::legacy::COLUMNS,
db::system_keyspace::legacy::TRIGGERS,
db::system_keyspace::legacy::USERTYPES,
db::system_keyspace::legacy::FUNCTIONS,
db::system_keyspace::legacy::AGGREGATES,
};
}
}
future<>
db::legacy_schema_migrator::migrate(sharded<service::storage_proxy>& sp, sharded<replica::database>& db, sharded<db::system_keyspace>& sys_ks, cql3::query_processor& qp) {
return do_with(migrator(sp, db, sys_ks, qp), std::bind(&migrator::migrate, std::placeholders::_1));
}