ClickHouse/src/Dictionaries/FileDictionarySource.cpp

#include "FileDictionarySource.h"

#include <filesystem>

#include <Poco/File.h>

#include <common/logger_useful.h>
#include <Common/StringUtils/StringUtils.h>
#include <Common/filesystemHelpers.h>
#include <DataStreams/OwningBlockInputStream.h>
#include <IO/ReadBufferFromFile.h>
#include <Interpreters/Context.h>
#include "DictionarySourceFactory.h"
#include "DictionaryStructure.h"
#include "registerDictionaries.h"
#include "DictionarySourceHelpers.h"

namespace fs = std::filesystem;

namespace DB
{
static const UInt64 max_block_size = 8192;

namespace ErrorCodes
{
    extern const int LOGICAL_ERROR;
    extern const int PATH_ACCESS_DENIED;
}


FileDictionarySource::FileDictionarySource(
    const std::string & filepath_, const std::string & format_,
    Block & sample_block_, ContextPtr context_, bool created_from_ddl)
    : filepath{filepath_}
    , format{format_}
    , sample_block{sample_block_}
    , context(context_)
{
    if (created_from_ddl && !pathStartsWith(filepath, context->getUserFilesPath()))
        throw Exception(ErrorCodes::PATH_ACCESS_DENIED, "File path {} is not inside {}", filepath, context->getUserFilesPath());
}


FileDictionarySource::FileDictionarySource(const FileDictionarySource & other)
    : filepath{other.filepath}
    , format{other.format}
    , sample_block{other.sample_block}
    , context(Context::createCopy(other.context))
    , last_modification{other.last_modification}
{
}


BlockInputStreamPtr FileDictionarySource::loadAll()
{
    LOG_TRACE(&Poco::Logger::get("FileDictionary"), "loadAll {}", toString());
    auto in_ptr = std::make_unique<ReadBufferFromFile>(filepath);
    auto stream = context->getInputFormat(format, *in_ptr, sample_block, max_block_size);
    last_modification = getLastModification();

    return std::make_shared<OwningBlockInputStream<ReadBuffer>>(stream, std::move(in_ptr));
}


std::string FileDictionarySource::toString() const
{
    return fmt::format("File: {}, {}", filepath, format);
}


Poco::Timestamp FileDictionarySource::getLastModification() const
{
    fs::file_time_type fs_time = fs::last_write_time(filepath);
    auto micro_sec = std::chrono::duration_cast<std::chrono::microseconds>(fs_time.time_since_epoch());
    return Poco::Timestamp(micro_sec.count());
}


void registerDictionarySourceFile(DictionarySourceFactory & factory)
{
    auto create_table_source = [=](const DictionaryStructure & dict_struct,
                                 const Poco::Util::AbstractConfiguration & config,
                                 const std::string & config_prefix,
                                 Block & sample_block,
                                 ContextPtr context,
                                 const std::string & /* default_database */,
                                 bool created_from_ddl) -> DictionarySourcePtr
    {
        if (dict_struct.has_expressions)
            throw Exception(ErrorCodes::LOGICAL_ERROR, "Dictionary source of type `file` does not support attribute expressions");

        const auto filepath = config.getString(config_prefix + ".file.path");
        const auto format = config.getString(config_prefix + ".file.format");

        auto context_local_copy = copyContextAndApplySettings(config_prefix, context, config);

        return std::make_unique<FileDictionarySource>(filepath, format, sample_block, context_local_copy, created_from_ddl);
    };

    factory.registerSource("file", create_table_source);
}

}