ClickHouse/dbms/src/Storages/StorageFile.cpp
alexey-milovidov fafecb3c25
Better modularity of formats. (#2492)
* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development): removed very old tests #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447

* Formats: better modularity (development) #2447
2018-06-10 22:22:49 +03:00

335 lines
11 KiB
C++

#include <Storages/StorageFile.h>
#include <Storages/StorageFactory.h>
#include <Interpreters/Context.h>
#include <Interpreters/evaluateConstantExpression.h>
#include <Parsers/ASTLiteral.h>
#include <Parsers/ASTIdentifier.h>
#include <IO/ReadBufferFromFile.h>
#include <IO/WriteBufferFromFile.h>
#include <IO/WriteHelpers.h>
#include <Formats/FormatFactory.h>
#include <DataStreams/IProfilingBlockInputStream.h>
#include <DataStreams/IBlockOutputStream.h>
#include <Common/escapeForFileName.h>
#include <Common/typeid_cast.h>
#include <fcntl.h>
#include <Poco/Path.h>
#include <Poco/File.h>
namespace DB
{
namespace ErrorCodes
{
extern const int CANNOT_WRITE_TO_FILE_DESCRIPTOR;
extern const int CANNOT_SEEK_THROUGH_FILE;
extern const int DATABASE_ACCESS_DENIED;
extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
extern const int UNKNOWN_IDENTIFIER;
extern const int INCORRECT_FILE_NAME;
extern const int FILE_DOESNT_EXIST;
extern const int EMPTY_LIST_OF_COLUMNS_PASSED;
};
static std::string getTablePath(const std::string & db_dir_path, const std::string & table_name, const std::string & format_name)
{
return db_dir_path + escapeForFileName(table_name) + "/data." + escapeForFileName(format_name);
}
/// Both db_dir_path and table_path must be converted to absolute paths (in particular, path cannot contain '..').
static void checkCreationIsAllowed(Context & context_global, const std::string & db_dir_path, const std::string & table_path, int table_fd)
{
if (context_global.getApplicationType() != Context::ApplicationType::SERVER)
return;
if (table_fd >= 0)
throw Exception("Using file descriptor as source of storage isn't allowed for server daemons", ErrorCodes::DATABASE_ACCESS_DENIED);
else if (!startsWith(table_path, db_dir_path))
throw Exception("Part path " + table_path + " is not inside " + db_dir_path, ErrorCodes::DATABASE_ACCESS_DENIED);
Poco::File table_path_poco_file = Poco::File(table_path);
if (!table_path_poco_file.exists())
throw Exception("File " + table_path + " is not exist", ErrorCodes::FILE_DOESNT_EXIST);
else if (table_path_poco_file.isDirectory())
throw Exception("File " + table_path + " must not be a directory", ErrorCodes::INCORRECT_FILE_NAME);
}
StorageFile::StorageFile(
const std::string & table_path_,
int table_fd_,
const std::string & db_dir_path,
const std::string & table_name_,
const std::string & format_name_,
const ColumnsDescription & columns_,
Context & context_)
: IStorage(columns_),
table_name(table_name_), format_name(format_name_), context_global(context_), table_fd(table_fd_)
{
if (table_fd < 0) /// Will use file
{
use_table_fd = false;
if (!table_path_.empty()) /// Is user's file
{
Poco::Path poco_path = Poco::Path(table_path_);
if (poco_path.isRelative())
poco_path = Poco::Path(db_dir_path, poco_path);
path = poco_path.absolute().toString();
checkCreationIsAllowed(context_global, db_dir_path, path, table_fd);
is_db_table = false;
}
else /// Is DB's file
{
if (db_dir_path.empty())
throw Exception("Storage " + getName() + " requires data path", ErrorCodes::INCORRECT_FILE_NAME);
path = getTablePath(db_dir_path, table_name, format_name);
is_db_table = true;
Poco::File(Poco::Path(path).parent()).createDirectories();
}
}
else /// Will use FD
{
checkCreationIsAllowed(context_global, db_dir_path, path, table_fd);
is_db_table = false;
use_table_fd = true;
/// Save initial offset, it will be used for repeating SELECTs
/// If FD isn't seekable (lseek returns -1), then the second and subsequent SELECTs will fail.
table_fd_init_offset = lseek(table_fd, 0, SEEK_CUR);
}
}
class StorageFileBlockInputStream : public IProfilingBlockInputStream
{
public:
StorageFileBlockInputStream(StorageFile & storage_, const Context & context, size_t max_block_size)
: storage(storage_)
{
if (storage.use_table_fd)
{
storage.rwlock.lock();
/// We could use common ReadBuffer and WriteBuffer in storage to leverage cache
/// and add ability to seek unseekable files, but cache sync isn't supported.
if (storage.table_fd_was_used) /// We need seek to initial position
{
if (storage.table_fd_init_offset < 0)
throw Exception("File descriptor isn't seekable, inside " + storage.getName(), ErrorCodes::CANNOT_SEEK_THROUGH_FILE);
/// ReadBuffer's seek() doesn't make sence, since cache is empty
if (lseek(storage.table_fd, storage.table_fd_init_offset, SEEK_SET) < 0)
throwFromErrno("Cannot seek file descriptor, inside " + storage.getName(), ErrorCodes::CANNOT_SEEK_THROUGH_FILE);
}
storage.table_fd_was_used = true;
read_buf = std::make_unique<ReadBufferFromFileDescriptor>(storage.table_fd);
}
else
{
storage.rwlock.lock_shared();
read_buf = std::make_unique<ReadBufferFromFile>(storage.path);
}
reader = FormatFactory::instance().getInput(storage.format_name, *read_buf, storage.getSampleBlock(), context, max_block_size);
}
~StorageFileBlockInputStream() override
{
if (storage.use_table_fd)
storage.rwlock.unlock();
else
storage.rwlock.unlock_shared();
}
String getName() const override
{
return storage.getName();
}
Block readImpl() override
{
return reader->read();
}
Block getHeader() const override { return reader->getHeader(); }
void readPrefixImpl() override
{
reader->readPrefix();
}
void readSuffixImpl() override
{
reader->readSuffix();
}
private:
StorageFile & storage;
Block sample_block;
std::unique_ptr<ReadBufferFromFileDescriptor> read_buf;
BlockInputStreamPtr reader;
};
BlockInputStreams StorageFile::read(
const Names & /*column_names*/,
const SelectQueryInfo & /*query_info*/,
const Context & context,
QueryProcessingStage::Enum & /*processed_stage*/,
size_t max_block_size,
unsigned /*num_streams*/)
{
return BlockInputStreams(1, std::make_shared<StorageFileBlockInputStream>(*this, context, max_block_size));
}
class StorageFileBlockOutputStream : public IBlockOutputStream
{
public:
explicit StorageFileBlockOutputStream(StorageFile & storage_)
: storage(storage_), lock(storage.rwlock)
{
if (storage.use_table_fd)
{
/** NOTE: Using real file binded to FD may be misleading:
* SELECT *; INSERT insert_data; SELECT *; last SELECT returns initil_fd_data + insert_data
* INSERT data; SELECT *; last SELECT returns only insert_data
*/
storage.table_fd_was_used = true;
write_buf = std::make_unique<WriteBufferFromFileDescriptor>(storage.table_fd);
}
else
{
write_buf = std::make_unique<WriteBufferFromFile>(storage.path, DBMS_DEFAULT_BUFFER_SIZE, O_WRONLY | O_APPEND | O_CREAT);
}
writer = FormatFactory::instance().getOutput(storage.format_name, *write_buf, storage.getSampleBlock(), storage.context_global);
}
Block getHeader() const override { return storage.getSampleBlock(); }
void write(const Block & block) override
{
writer->write(block);
}
void writePrefix() override
{
writer->writePrefix();
}
void writeSuffix() override
{
writer->writeSuffix();
}
void flush() override
{
writer->flush();
}
private:
StorageFile & storage;
std::unique_lock<std::shared_mutex> lock;
std::unique_ptr<WriteBufferFromFileDescriptor> write_buf;
BlockOutputStreamPtr writer;
};
BlockOutputStreamPtr StorageFile::write(
const ASTPtr & /*query*/,
const Settings & /*settings*/)
{
return std::make_shared<StorageFileBlockOutputStream>(*this);
}
void StorageFile::drop()
{
/// Extra actions are not required.
}
void StorageFile::rename(const String & new_path_to_db, const String & /*new_database_name*/, const String & new_table_name)
{
if (!is_db_table)
throw Exception("Can't rename table '" + table_name + "' binded to user-defined file (or FD)", ErrorCodes::DATABASE_ACCESS_DENIED);
std::unique_lock<std::shared_mutex> lock(rwlock);
std::string path_new = getTablePath(new_path_to_db, new_table_name, format_name);
Poco::File(Poco::Path(path_new).parent()).createDirectories();
Poco::File(path).renameTo(path_new);
path = std::move(path_new);
}
void registerStorageFile(StorageFactory & factory)
{
factory.registerStorage("File", [](const StorageFactory::Arguments & args)
{
ASTs & engine_args = args.engine_args;
if (!(engine_args.size() == 1 || engine_args.size() == 2))
throw Exception(
"Storage File requires 1 or 2 arguments: name of used format and source.",
ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
engine_args[0] = evaluateConstantExpressionOrIdentifierAsLiteral(engine_args[0], args.local_context);
String format_name = static_cast<const ASTLiteral &>(*engine_args[0]).value.safeGet<String>();
int source_fd = -1;
String source_path;
if (engine_args.size() >= 2)
{
/// Will use FD if engine_args[1] is int literal or identifier with std* name
if (const ASTIdentifier * identifier = typeid_cast<const ASTIdentifier *>(engine_args[1].get()))
{
if (identifier->name == "stdin")
source_fd = STDIN_FILENO;
else if (identifier->name == "stdout")
source_fd = STDOUT_FILENO;
else if (identifier->name == "stderr")
source_fd = STDERR_FILENO;
else
throw Exception("Unknown identifier '" + identifier->name + "' in second arg of File storage constructor",
ErrorCodes::UNKNOWN_IDENTIFIER);
}
else if (const ASTLiteral * literal = typeid_cast<const ASTLiteral *>(engine_args[1].get()))
{
auto type = literal->value.getType();
if (type == Field::Types::Int64)
source_fd = static_cast<int>(literal->value.get<Int64>());
else if (type == Field::Types::UInt64)
source_fd = static_cast<int>(literal->value.get<UInt64>());
else if (type == Field::Types::String)
source_path = literal->value.get<String>();
}
}
return StorageFile::create(
source_path, source_fd,
args.data_path,
args.table_name, format_name, args.columns,
args.context);
});
}
}