ClickHouse/src/Storages/StorageURL.h
Azat Khuzhin 4e76629aaf Fixes for -Wshorten-64-to-32
- lots of static_cast
- add safe_cast
- types adjustments
  - config
  - IStorage::read/watch
  - ...
- some TODO's (to convert types in future)

P.S. That was quite a journey...

v2: fixes after rebase
v3: fix conflicts after #42308 merged
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
2022-10-21 13:25:19 +02:00

222 lines
7.4 KiB
C++

#pragma once
#include <Storages/IStorage.h>
#include <Poco/URI.h>
#include <Processors/Sinks/SinkToStorage.h>
#include <Formats/FormatSettings.h>
#include <IO/CompressionMethod.h>
#include <IO/ReadWriteBufferFromHTTP.h>
#include <Storages/StorageFactory.h>
#include <Storages/ExternalDataSourceConfiguration.h>
#include <Storages/Cache/SchemaCache.h>
namespace DB
{
class IOutputFormat;
using OutputFormatPtr = std::shared_ptr<IOutputFormat>;
struct ConnectionTimeouts;
/**
* This class represents table engine for external urls.
* It sends HTTP GET to server when select is called and
* HTTP POST when insert is called. In POST request the data is send
* using Chunked transfer encoding, so server have to support it.
*/
class IStorageURLBase : public IStorage
{
public:
Pipe read(
const Names & column_names,
const StorageSnapshotPtr & storage_snapshot,
SelectQueryInfo & query_info,
ContextPtr context,
QueryProcessingStage::Enum processed_stage,
size_t max_block_size,
size_t num_streams) override;
SinkToStoragePtr write(const ASTPtr & query, const StorageMetadataPtr & /*metadata_snapshot*/, ContextPtr context) override;
bool supportsPartitionBy() const override { return true; }
static ColumnsDescription getTableStructureFromData(
const String & format,
const String & uri,
CompressionMethod compression_method,
const ReadWriteBufferFromHTTP::HTTPHeaderEntries & headers,
const std::optional<FormatSettings> & format_settings,
ContextPtr context);
static SchemaCache & getSchemaCache(const ContextPtr & context);
protected:
IStorageURLBase(
const String & uri_,
ContextPtr context_,
const StorageID & id_,
const String & format_name_,
const std::optional<FormatSettings> & format_settings_,
const ColumnsDescription & columns_,
const ConstraintsDescription & constraints_,
const String & comment,
const String & compression_method_,
const ReadWriteBufferFromHTTP::HTTPHeaderEntries & headers_ = {},
const String & method_ = "",
ASTPtr partition_by = nullptr);
String uri;
CompressionMethod compression_method;
String format_name;
// For URL engine, we use format settings from server context + `SETTINGS`
// clause of the `CREATE` query. In this case, format_settings is set.
// For `url` table function, we use settings from current query context.
// In this case, format_settings is not set.
std::optional<FormatSettings> format_settings;
ReadWriteBufferFromHTTP::HTTPHeaderEntries headers;
String http_method; /// For insert can choose Put instead of default Post.
ASTPtr partition_by;
virtual std::string getReadMethod() const;
virtual std::vector<std::pair<std::string, std::string>> getReadURIParams(
const Names & column_names,
const StorageSnapshotPtr & storage_snapshot,
const SelectQueryInfo & query_info,
ContextPtr context,
QueryProcessingStage::Enum & processed_stage,
size_t max_block_size) const;
virtual std::function<void(std::ostream &)> getReadPOSTDataCallback(
const Names & column_names,
const ColumnsDescription & columns_description,
const SelectQueryInfo & query_info,
ContextPtr context,
QueryProcessingStage::Enum & processed_stage,
size_t max_block_size) const;
bool supportsSubsetOfColumns() const override;
private:
virtual Block getHeaderBlock(const Names & column_names, const StorageSnapshotPtr & storage_snapshot) const = 0;
static std::optional<ColumnsDescription> tryGetColumnsFromCache(
const Strings & urls,
const ReadWriteBufferFromHTTP::HTTPHeaderEntries & headers,
const Poco::Net::HTTPBasicCredentials & credentials,
const String & format_name,
const std::optional<FormatSettings> & format_settings,
const ContextPtr & context);
static void addColumnsToCache(
const Strings & urls,
const ColumnsDescription & columns,
const String & format_name,
const std::optional<FormatSettings> & format_settings,
const ContextPtr & context);
static std::optional<time_t> getLastModificationTime(
const String & url,
const ReadWriteBufferFromHTTP::HTTPHeaderEntries & headers,
const Poco::Net::HTTPBasicCredentials & credentials,
const ContextPtr & context);
};
class StorageURLSink : public SinkToStorage
{
public:
StorageURLSink(
const String & uri,
const String & format,
const std::optional<FormatSettings> & format_settings,
const Block & sample_block,
ContextPtr context,
const ConnectionTimeouts & timeouts,
CompressionMethod compression_method,
const String & method = Poco::Net::HTTPRequest::HTTP_POST);
std::string getName() const override { return "StorageURLSink"; }
void consume(Chunk chunk) override;
void onCancel() override;
void onException() override;
void onFinish() override;
private:
void finalize();
std::unique_ptr<WriteBuffer> write_buf;
OutputFormatPtr writer;
std::mutex cancel_mutex;
bool cancelled = false;
};
class StorageURL : public IStorageURLBase
{
public:
StorageURL(
const String & uri_,
const StorageID & table_id_,
const String & format_name_,
const std::optional<FormatSettings> & format_settings_,
const ColumnsDescription & columns_,
const ConstraintsDescription & constraints_,
const String & comment,
ContextPtr context_,
const String & compression_method_,
const ReadWriteBufferFromHTTP::HTTPHeaderEntries & headers_ = {},
const String & method_ = "",
ASTPtr partition_by_ = nullptr);
String getName() const override
{
return "URL";
}
Block getHeaderBlock(const Names & /*column_names*/, const StorageSnapshotPtr & storage_snapshot) const override
{
return storage_snapshot->metadata->getSampleBlock();
}
static FormatSettings getFormatSettingsFromArgs(const StorageFactory::Arguments & args);
static URLBasedDataSourceConfiguration getConfiguration(ASTs & args, ContextPtr context);
static ASTs::iterator collectHeaders(ASTs & url_function_args, URLBasedDataSourceConfiguration & configuration, ContextPtr context);
};
/// StorageURLWithFailover is allowed only for URL table function, not as a separate storage.
class StorageURLWithFailover final : public StorageURL
{
public:
StorageURLWithFailover(
const std::vector<String> & uri_options_,
const StorageID & table_id_,
const String & format_name_,
const std::optional<FormatSettings> & format_settings_,
const ColumnsDescription & columns_,
const ConstraintsDescription & constraints_,
ContextPtr context_,
const String & compression_method_);
Pipe read(
const Names & column_names,
const StorageSnapshotPtr & storage_snapshot,
SelectQueryInfo & query_info,
ContextPtr context,
QueryProcessingStage::Enum processed_stage,
size_t max_block_size,
size_t num_streams) override;
struct Configuration
{
String url;
String compression_method = "auto";
std::vector<std::pair<String, String>> headers;
};
private:
std::vector<String> uri_options;
};
}