ClickHouse/src/Functions/filesystem.cpp
2023-04-29 18:55:19 +02:00

123 lines
4.1 KiB
C++

#include <Columns/ColumnString.h>
#include <Columns/ColumnVector.h>
#include <DataTypes/DataTypesNumber.h>
#include <Disks/IDisk.h>
#include <Functions/FunctionFactory.h>
#include <Functions/IFunction.h>
#include <Interpreters/Context.h>
#include <Poco/Util/AbstractConfiguration.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_COLUMN;
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
extern const int UNKNOWN_DISK;
}
namespace
{
struct FilesystemAvailable
{
static constexpr auto name = "filesystemAvailable";
static UInt64 get(const DiskPtr & disk) { return disk->getAvailableSpace().value_or(std::numeric_limits<UInt64>::max()); }
};
struct FilesystemUnreserved
{
static constexpr auto name = "filesystemUnreserved";
static UInt64 get(const DiskPtr & disk) { return disk->getUnreservedSpace().value_or(std::numeric_limits<UInt64>::max()); }
};
struct FilesystemCapacity
{
static constexpr auto name = "filesystemCapacity";
static UInt64 get(const DiskPtr & disk) { return disk->getTotalSpace().value_or(std::numeric_limits<UInt64>::max()); }
};
template <typename Impl>
class FilesystemImpl : public IFunction
{
public:
static constexpr auto name = Impl::name;
static FunctionPtr create(ContextPtr context_) { return std::make_shared<FilesystemImpl<Impl>>(context_); }
explicit FilesystemImpl(ContextPtr context_) : context(context_) { }
bool useDefaultImplementationForConstants() const override { return true; }
bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override
{
return false;
}
String getName() const override { return name; }
bool isVariadic() const override { return true; }
size_t getNumberOfArguments() const override { return 0; }
bool isDeterministic() const override { return false; }
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
if (arguments.size() > 1)
{
throw Exception(ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH, "Arguments size of function {} should be 0 or 1", getName());
}
if (arguments.size() == 1 && !isStringOrFixedString(arguments[0]))
{
throw Exception(ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT, "Arguments of function {} should be String or FixedString",
getName());
}
return std::make_shared<DataTypeUInt64>();
}
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t input_rows_count) const override
{
if (arguments.empty())
{
auto disk = context->getDisk("default");
return DataTypeUInt64().createColumnConst(input_rows_count, Impl::get(disk));
}
else
{
auto col = arguments[0].column;
if (const ColumnString * col_str = checkAndGetColumn<ColumnString>(col.get()))
{
auto disk_map = context->getDisksMap();
auto col_res = ColumnVector<UInt64>::create(col_str->size());
auto & data = col_res->getData();
for (size_t i = 0; i < col_str->size(); ++i)
{
auto disk_name = col_str->getDataAt(i).toString();
if (auto it = disk_map.find(disk_name); it != disk_map.end())
data[i] = Impl::get(it->second);
else
throw Exception(ErrorCodes::UNKNOWN_DISK, "Unknown disk name {} while execute function {}", disk_name, getName());
}
return col_res;
}
throw Exception(ErrorCodes::ILLEGAL_COLUMN, "Illegal column {} of argument of function {}",
arguments[0].column->getName(), getName());
}
}
private:
ContextPtr context;
};
}
REGISTER_FUNCTION(Filesystem)
{
factory.registerFunction<FilesystemImpl<FilesystemAvailable>>();
factory.registerFunction<FilesystemImpl<FilesystemCapacity>>();
factory.registerFunction<FilesystemImpl<FilesystemUnreserved>>();
}
}