mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-18 13:42:02 +00:00
131 lines
4.1 KiB
C++
131 lines
4.1 KiB
C++
#pragma once
|
|
|
|
#include <DB/Dictionaries/IDictionarySource.h>
|
|
#include <DB/Dictionaries/DictionaryStructure.h>
|
|
#include <DB/Dictionaries/ExternalQueryBuilder.h>
|
|
#include <DB/Client/ConnectionPool.h>
|
|
#include <DB/DataStreams/RemoteBlockInputStream.h>
|
|
#include <DB/Interpreters/executeQuery.h>
|
|
#include <DB/Common/isLocalAddress.h>
|
|
#include <ext/range.hpp>
|
|
#include <Poco/Util/AbstractConfiguration.h>
|
|
#include "writeParenthesisedString.h"
|
|
|
|
|
|
namespace DB
|
|
{
|
|
|
|
namespace ErrorCodes
|
|
{
|
|
extern const int UNSUPPORTED_METHOD;
|
|
}
|
|
|
|
|
|
const auto max_connections = 16;
|
|
|
|
/** Allows loading dictionaries from local or remote ClickHouse instance
|
|
* @todo use ConnectionPoolWithFailover
|
|
* @todo invent a way to keep track of source modifications
|
|
*/
|
|
class ClickHouseDictionarySource final : public IDictionarySource
|
|
{
|
|
public:
|
|
ClickHouseDictionarySource(const DictionaryStructure & dict_struct_,
|
|
const Poco::Util::AbstractConfiguration & config,
|
|
const std::string & config_prefix,
|
|
const Block & sample_block, Context & context)
|
|
: dict_struct{dict_struct_},
|
|
host{config.getString(config_prefix + ".host")},
|
|
port(config.getInt(config_prefix + ".port")),
|
|
user{config.getString(config_prefix + ".user", "")},
|
|
password{config.getString(config_prefix + ".password", "")},
|
|
db{config.getString(config_prefix + ".db", "")},
|
|
table{config.getString(config_prefix + ".table")},
|
|
where{config.getString(config_prefix + ".where", "")},
|
|
query_builder{dict_struct, db, table, where},
|
|
sample_block{sample_block}, context(context),
|
|
is_local{isLocalAddress({ host, port })},
|
|
pool{is_local ? nullptr : std::make_unique<ConnectionPool>(
|
|
max_connections, host, port, db, user, password,
|
|
"ClickHouseDictionarySource")
|
|
},
|
|
load_all_query{query_builder.composeLoadAllQuery()}
|
|
{}
|
|
|
|
/// copy-constructor is provided in order to support cloneability
|
|
ClickHouseDictionarySource(const ClickHouseDictionarySource & other)
|
|
: dict_struct{other.dict_struct},
|
|
host{other.host}, port{other.port}, user{other.user}, password{other.password},
|
|
db{other.db}, table{other.table},
|
|
where{other.where},
|
|
query_builder{dict_struct, db, table, where},
|
|
sample_block{other.sample_block}, context(other.context),
|
|
is_local{other.is_local},
|
|
pool{is_local ? nullptr : std::make_unique<ConnectionPool>(
|
|
max_connections, host, port, db, user, password,
|
|
"ClickHouseDictionarySource")},
|
|
load_all_query{other.load_all_query}
|
|
{}
|
|
|
|
BlockInputStreamPtr loadAll() override
|
|
{
|
|
/** Query to local ClickHouse is marked internal in order to avoid
|
|
* the necessity of holding process_list_element shared pointer.
|
|
*/
|
|
if (is_local)
|
|
return executeQuery(load_all_query, context, true).in;
|
|
return new RemoteBlockInputStream{pool.get(), load_all_query, nullptr};
|
|
}
|
|
|
|
BlockInputStreamPtr loadIds(const std::vector<std::uint64_t> & ids) override
|
|
{
|
|
return createStreamForSelectiveLoad(
|
|
query_builder.composeLoadIdsQuery(ids));
|
|
}
|
|
|
|
BlockInputStreamPtr loadKeys(
|
|
const ConstColumnPlainPtrs & key_columns, const std::vector<std::size_t> & requested_rows) override
|
|
{
|
|
return createStreamForSelectiveLoad(
|
|
query_builder.composeLoadKeysQuery(
|
|
key_columns, requested_rows, ExternalQueryBuilder::IN_WITH_TUPLES));
|
|
}
|
|
|
|
bool isModified() const override { return true; }
|
|
bool supportsSelectiveLoad() const override { return true; }
|
|
|
|
DictionarySourcePtr clone() const override { return std::make_unique<ClickHouseDictionarySource>(*this); }
|
|
|
|
std::string toString() const override
|
|
{
|
|
return "ClickHouse: " + db + '.' + table + (where.empty() ? "" : ", where: " + where);
|
|
}
|
|
|
|
private:
|
|
|
|
BlockInputStreamPtr createStreamForSelectiveLoad(const std::string query)
|
|
{
|
|
if (is_local)
|
|
return executeQuery(query, context, true).in;
|
|
return new RemoteBlockInputStream{pool.get(), query, nullptr};
|
|
}
|
|
|
|
|
|
const DictionaryStructure dict_struct;
|
|
const std::string host;
|
|
const UInt16 port;
|
|
const std::string user;
|
|
const std::string password;
|
|
const std::string db;
|
|
const std::string table;
|
|
const std::string where;
|
|
ExternalQueryBuilder query_builder;
|
|
Block sample_block;
|
|
Context & context;
|
|
const bool is_local;
|
|
std::unique_ptr<ConnectionPool> pool;
|
|
const std::string load_all_query;
|
|
};
|
|
|
|
}
|