ClickHouse/src/Dictionaries/XDBCDictionarySource.h
2021-06-10 11:34:57 +03:00

94 lines
2.4 KiB
C++

#pragma once
#include <IO/ConnectionTimeouts.h>
#include <Poco/Data/SessionPool.h>
#include <Poco/URI.h>
#include <Bridge/XDBCBridgeHelper.h>
#include "DictionaryStructure.h"
#include "ExternalQueryBuilder.h"
#include "IDictionarySource.h"
namespace Poco
{
namespace Util
{
class AbstractConfiguration;
}
class Logger;
}
namespace DB
{
/// Allows loading dictionaries from a XDBC source via bridges
class XDBCDictionarySource final : public IDictionarySource, WithContext
{
public:
struct Configuration
{
const std::string db;
const std::string schema;
const std::string table;
const std::string where;
const std::string invalidate_query;
const std::string update_field;
const UInt64 update_lag;
};
XDBCDictionarySource(
const DictionaryStructure & dict_struct_,
const Configuration & configuration_,
const Block & sample_block_,
ContextConstPtr context_,
BridgeHelperPtr bridge);
/// copy-constructor is provided in order to support cloneability
XDBCDictionarySource(const XDBCDictionarySource & other);
XDBCDictionarySource & operator=(const XDBCDictionarySource &) = delete;
BlockInputStreamPtr loadAll() override;
BlockInputStreamPtr loadUpdatedAll() override;
BlockInputStreamPtr loadIds(const std::vector<UInt64> & ids) override;
BlockInputStreamPtr loadKeys(const Columns & key_columns, const std::vector<size_t> & requested_rows) override;
bool isModified() const override;
bool supportsSelectiveLoad() const override;
bool hasUpdateField() const override;
DictionarySourcePtr clone() const override;
std::string toString() const override;
private:
std::string getUpdateFieldAndDate();
// execute invalidate_query. expects single cell in result
std::string doInvalidateQuery(const std::string & request) const;
BlockInputStreamPtr loadFromQuery(const Poco::URI & url, const Block & required_sample_block, const std::string & query) const;
Poco::Logger * log;
std::chrono::time_point<std::chrono::system_clock> update_time;
const DictionaryStructure dict_struct;
const Configuration configuration;
Block sample_block;
ExternalQueryBuilder query_builder;
const std::string load_all_query;
mutable std::string invalidate_query_response;
BridgeHelperPtr bridge_helper;
Poco::URI bridge_url;
ConnectionTimeouts timeouts;
};
}