add directory watcher

src/CMakeLists.txt

@@ -104,7 +104,11 @@ if (USE_HDFS)
     add_headers_and_sources(dbms Disks/HDFS)
 endif()
 
-add_headers_and_sources(dbms Storages/FileLog)
+set (USE_FILELOG 1)
+
+if(USE_FILELOG)
+    add_headers_and_sources(dbms Storages/FileLog)
+endif()
 
 list (APPEND clickhouse_common_io_sources ${CONFIG_BUILD})
 list (APPEND clickhouse_common_io_headers ${CONFIG_VERSION} ${CONFIG_COMMON})

src/Core/config_core.h.in

@@ -15,3 +15,4 @@
 #cmakedefine01 USE_LIBPQXX
 #cmakedefine01 USE_NURAFT
 #cmakedefine01 USE_KRB5
+#cmakedefine01 USE_FILELOG

src/Storages/FileLog/FileLogBlockInputStream.cpp

@@ -15,10 +15,6 @@ namespace ErrorCodes
     extern const int LOGICAL_ERROR;
 }
 
-// with default poll timeout (500ms) it will give about 5 sec delay for doing 10 retries
-// when selecting from empty topic
-const auto MAX_FAILED_POLL_ATTEMPTS = 10;
-
 FileLogBlockInputStream::FileLogBlockInputStream(
     StorageFileLog & storage_,
     const StorageMetadataPtr & metadata_snapshot_,
@@ -55,15 +51,10 @@ void FileLogBlockInputStream::readPrefixImpl()
 
 Block FileLogBlockInputStream::readImpl()
 {
-    if (!buffer || finished)
+    if (!buffer)
         return Block();
 
-    finished = true;
-    // now it's one-time usage InputStream
-    // one block of the needed size (or with desired flush timeout) is formed in one internal iteration
-    // otherwise external iteration will reuse that and logic will became even more fuzzy
     MutableColumns result_columns  = non_virtual_header.cloneEmptyColumns();
-    // MutableColumns virtual_columns = virtual_header.cloneEmptyColumns();
 
     auto input_format = FormatFactory::instance().getInputFormat(
         storage.getFormatName(), *buffer, non_virtual_header, context, max_block_size);
@@ -93,8 +84,6 @@ Block FileLogBlockInputStream::readImpl()
                 {
                     auto chunk = port.pull();
 
-                    // that was returning bad value before https://github.com/ClickHouse/ClickHouse/pull/8005
-                    // if will be backported should go together with #8005
                     auto chunk_rows = chunk.getNumRows();
                     new_rows += chunk_rows;
 
@@ -125,7 +114,7 @@ Block FileLogBlockInputStream::readImpl()
             {
                 new_rows = read_file_log();
             }
-            catch (Exception & e)
+            catch (Exception &)
             {
                 throw;
             }
@@ -133,6 +122,7 @@ Block FileLogBlockInputStream::readImpl()
         if (new_rows)
         {
             total_rows = total_rows + new_rows;
+            LOG_INFO(log, "FileLogBlockInputStream, {} rows data polled from buffer.", new_rows);
         }
 
         if (!buffer->hasMorePolledRecords() && (total_rows >= max_block_size || !checkTimeLimit()))
@@ -144,18 +134,7 @@ Block FileLogBlockInputStream::readImpl()
     if (total_rows == 0)
         return Block();
 
-    /// MATERIALIZED columns can be added here, but I think
-    // they are not needed here:
-    // and it's misleading to use them here,
-    // as columns 'materialized' that way stays 'ephemeral'
-    // i.e. will not be stored anythere
-    // If needed any extra columns can be added using DEFAULT they can be added at MV level if needed.
-
     auto result_block  = non_virtual_header.cloneWithColumns(std::move(result_columns));
-    // auto virtual_block = virtual_header.cloneWithColumns(std::move(virtual_columns));
-
-    // for (const auto & column : virtual_block.getColumnsWithTypeAndName())
-        // result_block.insert(column);
 
     return ConvertingBlockInputStream(
                std::make_shared<OneBlockInputStream>(result_block),

src/Storages/FileLog/FileLogDirectoryWatcher.cpp

@@ -0,0 +1,89 @@
+#include <Storages/FileLog/FileLogDirectoryWatcher.h>
+#include <Poco/Delegate.h>
+#include <Poco/DirectoryWatcher.h>
+
+FileLogDirectoryWatcher::FileLogDirectoryWatcher(const std::string & path_)
+    : path(path_), dw(std::make_shared<Poco::DirectoryWatcher>(path))
+{
+    dw->itemAdded += Poco::delegate(this, &FileLogDirectoryWatcher::onItemAdded);
+    dw->itemRemoved += Poco::delegate(this, &FileLogDirectoryWatcher::onItemRemoved);
+    dw->itemModified += Poco::delegate(this, &FileLogDirectoryWatcher::onItemModified);
+    dw->itemMovedFrom += Poco::delegate(this, &FileLogDirectoryWatcher::onItemMovedFrom);
+    dw->itemMovedTo += Poco::delegate(this, &FileLogDirectoryWatcher::onItemMovedTo);
+}
+
+FileLogDirectoryWatcher::Events FileLogDirectoryWatcher::getEvents()
+{
+    std::lock_guard<std::mutex> lock(mutex);
+    Events res;
+    res.swap(events);
+    return res;
+}
+
+bool FileLogDirectoryWatcher::getError() const
+{
+    return error;
+}
+
+const std::string & FileLogDirectoryWatcher::getPath() const
+{
+    return path;
+}
+
+void FileLogDirectoryWatcher::onItemAdded(const Poco::DirectoryWatcher::DirectoryEvent& ev)
+{
+    std::lock_guard<std::mutex> lock(mutex);
+    DirEvent de;
+	de.callback = "onItemAdded";
+	de.path = ev.item.path();
+	de.type = ev.event;
+	events.push_back(de);
+}
+
+
+void FileLogDirectoryWatcher::onItemRemoved(const Poco::DirectoryWatcher::DirectoryEvent& ev)
+{
+    std::lock_guard<std::mutex> lock(mutex);
+	DirEvent de;
+	de.callback = "onItemRemoved";
+	de.path = ev.item.path();
+	de.type = ev.event;
+	events.push_back(de);
+}
+
+
+void FileLogDirectoryWatcher::onItemModified(const Poco::DirectoryWatcher::DirectoryEvent& ev)
+{
+    std::lock_guard<std::mutex> lock(mutex);
+	DirEvent de;
+	de.callback = "onItemModified";
+	de.path = ev.item.path();
+	de.type = ev.event;
+	events.push_back(de);
+}
+
+void FileLogDirectoryWatcher::onItemMovedFrom(const Poco::DirectoryWatcher::DirectoryEvent& ev)
+{
+    std::lock_guard<std::mutex> lock(mutex);
+    DirEvent de;
+	de.callback = "onItemMovedFrom";
+	de.path = ev.item.path();
+	de.type = ev.event;
+	events.push_back(de);
+}
+
+void FileLogDirectoryWatcher::onItemMovedTo(const Poco::DirectoryWatcher::DirectoryEvent& ev)
+{
+    std::lock_guard<std::mutex> lock(mutex);
+	DirEvent de;
+	de.callback = "onItemMovedTo";
+	de.path = ev.item.path();
+	de.type = ev.event;
+	events.push_back(de);
+}
+
+
+void FileLogDirectoryWatcher::onError(const Poco::Exception &)
+{
+	error = true;
+}

src/Storages/FileLog/FileLogDirectoryWatcher.h

@@ -0,0 +1,48 @@
+#pragma once
+
+#include <Poco/DirectoryWatcher.h>
+#include <Poco/Foundation.h>
+#include <Poco/Path.h>
+
+#include <deque>
+#include <mutex>
+
+class FileLogDirectoryWatcher
+{
+public:
+    struct DirEvent
+	{
+		Poco::DirectoryWatcher::DirectoryEventType type;
+		std::string callback;
+		std::string path;
+	};
+
+    using Events = std::deque<DirEvent>;
+
+    explicit FileLogDirectoryWatcher(const std::string & path_);
+    ~FileLogDirectoryWatcher() = default;
+
+    Events getEvents();
+
+    bool getError() const;
+
+    const std::string & getPath() const;
+
+protected:
+    void onItemAdded(const Poco::DirectoryWatcher::DirectoryEvent& ev);
+	void onItemRemoved(const Poco::DirectoryWatcher::DirectoryEvent& ev);
+	void onItemModified(const Poco::DirectoryWatcher::DirectoryEvent& ev);
+	void onItemMovedFrom(const Poco::DirectoryWatcher::DirectoryEvent& ev);
+	void onItemMovedTo(const Poco::DirectoryWatcher::DirectoryEvent& ev);
+    void onError(const Poco::Exception &);
+
+private:
+    const std::string path;
+    std::shared_ptr<Poco::DirectoryWatcher> dw;
+
+    std::mutex mutex;
+
+    Events events;
+
+    bool error = false;
+};

src/Storages/FileLog/ReadBufferFromFileLog.cpp

@@ -1,5 +1,7 @@
 #include <Interpreters/Context.h>
 #include <Storages/FileLog/ReadBufferFromFileLog.h>
+#include <Poco/DirectoryIterator.h>
+#include <Poco/File.h>
 
 #include <common/logger_useful.h>
 #include <common/sleep.h>
@@ -15,33 +17,49 @@ namespace ErrorCodes
     extern const int CANNOT_COMMIT_OFFSET;
 }
 
-using namespace std::chrono_literals;
-
 ReadBufferFromFileLog::ReadBufferFromFileLog(
-    const std::vector<String> & log_files_,
-    Poco::Logger * log_,
-    size_t max_batch_size,
-    size_t poll_timeout_,
-    ContextPtr context_)
+    const String & path_, Poco::Logger * log_, size_t max_batch_size, size_t poll_timeout_, ContextPtr context_)
     : ReadBuffer(nullptr, 0)
+    , path(path_)
     , log(log_)
     , batch_size(max_batch_size)
     , poll_timeout(poll_timeout_)
     , context(context_)
-    , log_files(log_files_.begin(), log_files_.end())
 {
 }
 
 void ReadBufferFromFileLog::open()
 {
-    for (const auto & file : log_files)
-        file_status[file].reader = std::ifstream(file);
+    Poco::File file(path);
+
+    bool path_is_directory = false;
+
+    if (file.isFile())
+    {
+        file_status[path].reader = std::ifstream(path);
+    }
+    else if (file.isDirectory())
+    {
+        path_is_directory = true;
+        Poco::DirectoryIterator dir_iter(file);
+        Poco::DirectoryIterator end;
+        while (dir_iter != end)
+        {
+            if (dir_iter->isFile())
+                file_status[dir_iter->path()].reader = std::ifstream(dir_iter->path());
+            ++dir_iter;
+        }
+    }
 
     wait_task = context->getMessageBrokerSchedulePool().createTask("waitTask", [this] { waitFunc(); });
     wait_task->deactivate();
 
-    select_task = context->getMessageBrokerSchedulePool().createTask("selectTask", [this] { selectFunc(); });
+    if (path_is_directory)
+    {
+        FileLogDirectoryWatcher dw(path);
+        select_task = context->getMessageBrokerSchedulePool().createTask("watchTask", [this, &dw] { watchFunc(dw); });
         select_task->activateAndSchedule();
+    }
 
     cleanUnprocessed();
     allowed = false;
@@ -63,7 +81,6 @@ void ReadBufferFromFileLog::close()
         status.second.reader.close();
 }
 
-// it do the poll when needed
 bool ReadBufferFromFileLog::poll()
 {
 
@@ -113,10 +130,19 @@ ReadBufferFromFileLog::Records ReadBufferFromFileLog::pollBatch(size_t batch_siz
 
 void ReadBufferFromFileLog::readNewRecords(ReadBufferFromFileLog::Records & new_records, size_t batch_size_)
 {
+    std::lock_guard<std::mutex> lock(status_mutex);
+
     size_t need_records_size = batch_size_ - new_records.size();
     size_t read_records_size = 0;
+
     for (auto & status : file_status)
     {
+        if (status.second.status == FileStatus::NO_CHANGE)
+            continue;
+
+        if (status.second.status == FileStatus::REMOVED)
+            file_status.erase(status.first);
+
         while (read_records_size < need_records_size && status.second.reader.good() && !status.second.reader.eof())
         {
             Record record;
@@ -124,6 +150,11 @@ void ReadBufferFromFileLog::readNewRecords(ReadBufferFromFileLog::Records & new_
             new_records.emplace_back(record);
             ++read_records_size;
         }
+
+        // Read to the end of the file
+        if (status.second.reader.eof())
+            status.second.status = FileStatus::NO_CHANGE;
+
         if (read_records_size == need_records_size)
             break;
     }
@@ -149,8 +180,41 @@ void ReadBufferFromFileLog::waitFunc()
     time_out = true;
 }
 
-void ReadBufferFromFileLog::selectFunc()
+void ReadBufferFromFileLog::watchFunc(FileLogDirectoryWatcher & dw)
 {
-}
-}
+    while (true)
+    {
+        sleepForNanoseconds(poll_timeout);
 
+        auto error = dw.getError();
+        if (error)
+            LOG_INFO(log, "Error happened during watching directory {}.", dw.getPath());
+
+        auto events = dw.getEvents();
+        std::lock_guard<std::mutex> lock(status_mutex);
+
+        for (const auto & event : events)
+        {
+            switch (event.type)
+            {
+                case Poco::DirectoryWatcher::DW_ITEM_ADDED:
+                    file_status[event.path].reader = std::ifstream(event.path);
+                    break;
+
+                case Poco::DirectoryWatcher::DW_ITEM_MODIFIED:
+                    file_status[event.path].status = FileStatus::UPDATED;
+                    break;
+
+                case Poco::DirectoryWatcher::DW_ITEM_REMOVED:
+                case Poco::DirectoryWatcher::DW_ITEM_MOVED_TO:
+                case Poco::DirectoryWatcher::DW_ITEM_MOVED_FROM:
+                    file_status[event.path].status = FileStatus::REMOVED;
+                    break;
+
+                default:
+                    LOG_INFO(log, "Undefine event type");
+            }
+        }
+    }
+}
+}

src/Storages/FileLog/ReadBufferFromFileLog.h

@@ -3,6 +3,7 @@
 #include <Core/BackgroundSchedulePool.h>
 #include <Core/Names.h>
 #include <IO/ReadBuffer.h>
+#include <Storages/FileLog/FileLogDirectoryWatcher.h>
 #include <common/types.h>
 
 #include <fstream>
@@ -19,12 +20,7 @@ namespace DB
 class ReadBufferFromFileLog : public ReadBuffer
 {
 public:
-    ReadBufferFromFileLog(
-        const std::vector<String> & log_files_,
-        Poco::Logger * log_,
-        size_t max_batch_size,
-        size_t poll_timeout_,
-        ContextPtr context_);
+    ReadBufferFromFileLog(const String & path_, Poco::Logger * log_, size_t max_batch_size, size_t poll_timeout_, ContextPtr context_);
 
     ~ReadBufferFromFileLog() override = default;
 
@@ -48,11 +44,12 @@ private:
 
     struct FileContext
     {
-        std::mutex status_mutex;
         FileStatus status = FileStatus::BEGIN;
         std::ifstream reader;
     };
 
+    const String path;
+
     Poco::Logger * log;
     const size_t batch_size = 1;
     const size_t poll_timeout = 0;
@@ -62,12 +59,12 @@ private:
     using NameToFile = std::unordered_map<String, FileContext>;
     NameToFile file_status;
 
+    std::mutex status_mutex;
+
     ContextPtr context;
 
     bool allowed = true;
 
-    const std::vector<String> log_files;
-
     using Record = std::string;
     using Records = std::vector<Record>;
 
@@ -83,13 +80,12 @@ private:
 
     void readNewRecords(Records & new_records, size_t batch_size_);
 
-    // void drain();
     void cleanUnprocessed();
 
     bool nextImpl() override;
 
     void waitFunc();
 
-    void selectFunc();
+    void watchFunc(FileLogDirectoryWatcher & dw);
 };
 }

src/Storages/FileLog/StorageFileLog.cpp

@@ -23,7 +23,6 @@
 #include <Storages/StorageFactory.h>
 #include <Storages/StorageMaterializedView.h>
 #include <Poco/DirectoryIterator.h>
-#include <Poco/DirectoryWatcher.h>
 #include <Poco/File.h>
 #include <Common/Exception.h>
 #include <Common/Macros.h>
@@ -67,24 +66,6 @@ StorageFileLog::StorageFileLog(
     storage_metadata.setColumns(columns_);
     setInMemoryMetadata(storage_metadata);
 
-    Poco::File file(path);
-
-    if (file.isFile())
-    {
-        log_files.emplace_back(path);
-    }
-    else if (file.isDirectory())
-    {
-        Poco::DirectoryIterator dir_iter(file);
-        Poco::DirectoryIterator end;
-        while (dir_iter != end)
-        {
-            if (dir_iter->isFile())
-                log_files.emplace_back(dir_iter->path());
-            ++dir_iter;
-        }
-    }
-
     auto thread = getContext()->getMessageBrokerSchedulePool().createTask(log->name(), [this] { threadFunc(); });
     thread->deactivate();
     task = std::make_shared<TaskContext>(std::move(thread));
@@ -157,7 +138,6 @@ bool StorageFileLog::checkDependencies(const StorageID & table_id)
     if (dependencies.empty())
         return true;
 
-    // Check the dependencies are ready?
     for (const auto & db_tab : dependencies)
     {
         auto table = DatabaseCatalog::instance().tryGetTable(db_tab, getContext());
@@ -180,7 +160,7 @@ bool StorageFileLog::checkDependencies(const StorageID & table_id)
 void StorageFileLog::createReadBuffer()
 {
     auto new_context = Context::createCopy(getContext());
-    buffer = std::make_shared<ReadBufferFromFileLog>(log_files, log, getPollMaxBatchSize(), getPollTimeoutMillisecond(), new_context);
+    buffer = std::make_shared<ReadBufferFromFileLog>(path, log, getPollMaxBatchSize(), getPollTimeoutMillisecond(), new_context);
 }
 
 void StorageFileLog::destroyReadBuffer()
@@ -208,13 +188,7 @@ void StorageFileLog::threadFunc()
 
                 LOG_DEBUG(log, "Started streaming to {} attached views", dependencies_count);
 
-                // Exit the loop & reschedule if some stream stalled
-                auto some_stream_is_stalled = streamToViews();
-                if (some_stream_is_stalled)
-                {
-                    LOG_TRACE(log, "Stream(s) stalled. Reschedule.");
-                    break;
-                }
+                streamToViews();
 
                 auto ts = std::chrono::steady_clock::now();
                 auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(ts-start_time);
@@ -255,14 +229,12 @@ bool StorageFileLog::streamToViews()
 
     auto new_context = Context::createCopy(getContext());
 
-    // Only insert into dependent views and expect that input blocks contain virtual columns
     InterpreterInsertQuery interpreter(insert, new_context, false, true, true);
     auto block_io = interpreter.execute();
 
     auto stream = std::make_shared<FileLogBlockInputStream>(
         *this, metadata_snapshot, new_context, block_io.out->getHeader().getNames(), log, block_size);
 
-    // Limit read batch to maximum block size to allow DDL
     StreamLocalLimits limits;
 
     limits.speed_limits.max_execution_time = getContext()->getSettingsRef().stream_flush_interval_ms;
@@ -270,8 +242,6 @@ bool StorageFileLog::streamToViews()
     limits.timeout_overflow_mode = OverflowMode::BREAK;
     stream->setLimits(limits);
 
-    // We can't cancel during copyData, as it's not aware of commits and other kafka-related stuff.
-    // It will be cancelled on underlying layer (kafka buffer)
     std::atomic<bool> stub = {false};
     size_t rows = 0;
     copyData(

src/Storages/FileLog/StorageFileLog.h

@@ -59,8 +59,6 @@ private:
     const String format_name;
     Poco::Logger * log;
 
-    Files log_files;
-
     ReadBufferFromFileLogPtr buffer;
 
     std::mutex mutex;

src/Storages/System/StorageSystemBuildOptions.generated.cpp.in

@@ -50,6 +50,8 @@ const char * auto_config_build[]
     "USE_LDAP", "@USE_LDAP@",
     "TZDATA_VERSION", "@TZDATA_VERSION@",
     "USE_KRB5", "@USE_KRB5@",
+    "USE_KRB5", "@USE_KRB5@",
+    "USE_FILELOG", "@USE_FILELOG@",
 
     nullptr, nullptr
 };

src/Storages/registerStorages.cpp

@@ -50,8 +50,6 @@ void registerStorageMongoDB(StorageFactory & factory);
 void registerStorageKafka(StorageFactory & factory);
 #endif
 
-void registerStorageFileLog(StorageFactory & factory);
-
 #if USE_AMQPCPP
 void registerStorageRabbitMQ(StorageFactory & factory);
 #endif
@@ -69,6 +67,10 @@ void registerStorageMaterializedPostgreSQL(StorageFactory & factory);
 void registerStorageExternalDistributed(StorageFactory & factory);
 #endif
 
+#if USE_FILELOG
+void registerStorageFileLog(StorageFactory & factory);
+#endif
+
 void registerStorages()
 {
     auto & factory = StorageFactory::instance();
@@ -114,7 +116,9 @@ void registerStorages()
     registerStorageKafka(factory);
     #endif
 
+#if USE_FILELOG
     registerStorageFileLog(factory);
+#endif
 
 #if USE_AMQPCPP
     registerStorageRabbitMQ(factory);