Add MetadataFile / Replicator class and initial IOC-write logic.

CMakeLists.txt

@@ -29,6 +29,8 @@ set(storagemanager_SRCS
     src/Downloader.cpp
     src/Synchronizer.cpp
     src/RWLock.cpp
+    src/MetadataFile.cpp
+    src/Replicator.cpp
 )
 
 option(TRACE "Enable some tracing output" OFF)

src/IOCoordinator.cpp

@@ -1,5 +1,7 @@
 
 #include "IOCoordinator.h"
+#include "Cache.h"
+#include "MetadataFile.h"
 #include "SMLogging.h"
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -8,8 +10,6 @@
 #include <errno.h>
 #include <boost/filesystem.hpp>
 #include <boost/property_tree/json_parser.hpp>
-#include <boost/uuid/uuid.hpp>
-#include <boost/uuid/uuid_io.hpp>
 #include <iostream>
 
 #define max(x, y) (x > y ? x : y)
@@ -30,6 +30,7 @@ IOCoordinator::IOCoordinator()
 {
     config = Config::get();
     logger = SMLogging::get();
+    replicator = Replicator::get();
     objectSize = 5 * (1<<20);
     try 
     {
@@ -101,21 +102,77 @@ int IOCoordinator::read(const char *filename, uint8_t *data, off_t offset, size_
 
 int IOCoordinator::write(const char *filename, const uint8_t *data, off_t offset, size_t length)
 {
-    int fd, err;
+    int err = 0;
+    uint64_t count = 0;
+    uint64_t writelength = 0;
+    uint64_t dataRemaining = length;
+    uint64_t journalOffset = 0;
+    bool updateMeta = false;
+    vector<metadataObject> objects;
 
-    OPEN(filename, O_WRONLY);
-    size_t count = 0;
-    ::lseek(fd, offset, SEEK_SET);
-    while (count < length) {
-        err = ::write(fd, &data[count], length - count);
-        if (err <= 0)
-            if (count > 0)   // return what was successfully written
-                return count;
+    //writeLock(filename);
+
+    MetadataFile metadata = MetadataFile(filename);
+
+    //read metadata determine how many objects overlap
+    objects = metadata.metadataRead(offset,length);
+
+    // if there are objects append the journalfile in replicator
+    if(!objects.empty())
+    {
+        for (std::vector<metadataObject>::const_iterator i = objects.begin(); i != objects.end(); ++i)
+        {
+            // figure out how much data to write to this object
+            if (count == 0 && offset > i->offset)
+            {
+                // first object in the list so start at offset and
+                // write to end of oject or all the data
+                journalOffset = offset - i->offset;
+                writelength = min((objectSize - journalOffset),dataRemaining);
+            }
             else
-                return err;
-        count += err;
+            {
+                // starting at beginning of next object write the rest of data
+                // or until object length is reached
+                writelength = min(objectSize,dataRemaining);
+                journalOffset = 0;
+            }
+            err = replicator->addJournalEntry(i->name.c_str(),&data[count],journalOffset,writelength);
+            if (err <= 0)
+            {
+                //log error and abort
+            }
+            count += err;
+            dataRemaining -= err;
+        }
+        //cache.makeSpace(journal_data_size)
+        //Synchronizer::newJournalData(journal_file);
     }
 
+    // there is no overlapping data, or data goes beyond end of last object
+    while (dataRemaining > 0 && err >= 0)
+    {
+        //add a new metaDataObject
+        writelength = min(objectSize,dataRemaining);
+        //cache.makeSpace(size)
+        // add a new metadata object, this will get a new objectKey
+        metadataObject newObject = metadata.addMetadataObject(filename,writelength);
+        // write the new object
+        err = replicator->newObject(newObject.name.c_str(),data,writelength);
+        if (err <= 0)
+        {
+            //log error and abort
+        }
+        // sync
+        //Synchronizer::newObject(newname)
+        count += err;
+        dataRemaining -= err;
+    }
+
+    metadata.updateMetadata(filename);
+    
+    //writeUnlock(filename);
+
     return count;
 }
 
@@ -263,11 +320,11 @@ boost::shared_array<uint8_t> IOCoordinator::mergeJournal(const char *object, con
     
     objFD = ::open(object, O_RDONLY);
     if (objFD < 0)
-        return NULL;
+        return ret;
     scoped_closer s1(objFD);
     journalFD = ::open(journal, O_RDONLY);
     if (journalFD < 0)
-        return NULL;
+        return ret;
     scoped_closer s2(journalFD);
     
     // TODO: Right now this assumes that max object size has not been changed.
@@ -414,27 +471,6 @@ int IOCoordinator::mergeJournalInMem(uint8_t *objData, const char *journalPath)
     return 0;
 }
 
-string IOCoordinator::getNewKeyFromOldKey(const string &oldKey)
-{
-    boost::uuids::uuid u;
-    string ret(oldKey);
-    strcpy(&ret[0], boost::uuids::to_string(u).c_str());
-    return ret;
-}
-
-string IOCoordinator::getNewKey(string sourceName, size_t offset, size_t length)
-{
-    boost::uuids::uuid u;
-    stringstream ss;
-    
-    for (int i = 0; i < sourceName.length(); i++)
-        if (sourceName[i] == '/')
-            sourceName[i] = '-';
-    
-    ss << u << "_" << offset << "_" << length << "_" << sourceName;
-    return ss.str();
-}
-
 bool IOCoordinator::readLock(const string &filename)
 {
     boost::unique_lock<boost::mutex> s(lockMutex);

src/IOCoordinator.h

@@ -14,10 +14,13 @@
 #include "Config.h"
 #include "SMLogging.h"
 #include "RWLock.h"
+#include "Replicator.h"
 
 namespace storagemanager
 {
 
+boost::shared_array<char> seekToEndOfHeader1(int fd);
+
 class IOCoordinator : public boost::noncopyable
 {
     public:
@@ -35,10 +38,6 @@ class IOCoordinator : public boost::noncopyable
         int unlink(const char *path);
         int copyFile(const char *filename1, const char *filename2);
         
-        // TBD: this may have to go; there may be no use case where only the uuid needs to change.
-        std::string getNewKeyFromOldKey(const std::string &oldKey);
-        std::string getNewKey(std::string sourceName, size_t offset, size_t length);
-        
         // The shared logic for merging a journal file with its base file.
         // The default values for offset and len mean 'process the whole file'.  Otherwise,
         // offset is relative to the object.
@@ -55,6 +54,7 @@ class IOCoordinator : public boost::noncopyable
         IOCoordinator();
         Config *config;
         SMLogging *logger;
+        Replicator *replicator;
         size_t objectSize;
         
         std::map<std::string, RWLock *> locks;

src/MetadataFile.cpp

@@ -0,0 +1,203 @@
+/*
+ * MetadataFile.cpp
+ */
+#include "MetadataFile.h"
+#include <boost/filesystem.hpp>
+#include <boost/property_tree/ptree.hpp>
+#include <boost/property_tree/json_parser.hpp>
+#include <boost/foreach.hpp>
+#include <boost/uuid/uuid.hpp>
+#include <boost/uuid/uuid_io.hpp>
+
+#define max(x, y) (x > y ? x : y)
+#define min(x, y) (x < y ? x : y)
+
+namespace storagemanager
+{
+
+MetadataFile::MetadataFile()
+{
+    mpConfig = Config::get();
+    mpLogger = SMLogging::get();
+    mObjectSize = 5 * (1<<20);
+    try 
+    {
+        mObjectSize = stoul(mpConfig->getValue("ObjectStorage", "object_size"));
+    }
+    catch (...)
+    {
+        cerr << "ObjectStorage/object_size must be set to a numeric value" << endl;
+        throw;
+    }
+    mVersion=1;
+    mRevision=1;
+}
+
+
+MetadataFile::MetadataFile(const char* filename)
+{
+    mpConfig = Config::get();
+    mpLogger = SMLogging::get();
+    mObjectSize = 5 * (1<<20);
+    try
+    {
+        mObjectSize = stoul(mpConfig->getValue("ObjectStorage", "object_size"));
+    }
+    catch (...)
+    {
+        cerr << "ObjectStorage/object_size must be set to a numeric value" << endl;
+        throw;
+    }
+    string metadataFilename = string(filename) + ".meta";
+    if (boost::filesystem::exists(metadataFilename))
+    {
+        boost::property_tree::ptree jsontree;
+        boost::property_tree::read_json(metadataFilename, jsontree);
+        metadataObject newObject;
+        mVersion = jsontree.get<int>("version");
+        mRevision = jsontree.get<int>("revision");
+
+        BOOST_FOREACH(const boost::property_tree::ptree::value_type &v, jsontree.get_child("objects"))
+        {
+            metadataObject newObject;
+            newObject.offset = v.second.get<uint64_t>("offset");
+            newObject.length = v.second.get<uint64_t>("length");
+            newObject.name = v.second.get<string>("name");
+            mObjects.push_back(newObject);
+        }
+    }
+    else
+    {
+        mVersion = 1;
+        mRevision = 1;
+        updateMetadata(filename);
+    }
+}
+
+MetadataFile::~MetadataFile()
+{
+
+}
+
+vector<metadataObject> MetadataFile::metadataRead(off_t offset, size_t length)
+{
+    vector<metadataObject> returnObjs;
+    uint64_t startData = offset;
+    uint64_t endData = offset + length;
+    uint64_t dataRemaining = length;
+    bool foundStart = false;
+    for (std::vector<metadataObject>::iterator i = mObjects.begin(); i != mObjects.end(); ++i)
+    {
+        uint64_t startObject = i->offset;
+        uint64_t endObject = i->offset + i->length;
+        uint64_t maxEndObject = i->offset + mObjectSize;
+        // This logic assumes objects are in ascending order of offsets
+        if (startData >= startObject && (startData < endObject || startData < maxEndObject))
+        {
+            returnObjs.push_back(*i);
+            if (startData >= endObject)
+            {
+                // data starts and the end of current object and can atleast partially fit here update length
+                i->length += min((maxEndObject-startData),dataRemaining);
+            }
+            foundStart = true;
+        }
+        else if (endData >= startObject && (endData < endObject || endData < maxEndObject))
+        {
+            // data ends in this object
+            returnObjs.push_back(*i);
+            if (endData >= endObject)
+            {
+                // data end is beyond old length
+                i->length += (endData - endObject);
+            }
+        }
+        else if (endData >= startObject && foundStart)
+        {
+            // data overlaps this object
+            returnObjs.push_back(*i);
+        }
+    }
+
+    return returnObjs;
+}
+
+metadataObject MetadataFile::addMetadataObject(const char *filename, size_t length)
+{
+    metadataObject addObject,lastObject;
+    if (!mObjects.empty())
+    {
+        metadataObject lastObject = mObjects.back();
+        addObject.offset = lastObject.offset + lastObject.length;
+    }
+    else
+    {
+        addObject.offset = 0;
+    }
+    addObject.length = length;
+    string newObjectKey = getNewKey(filename, addObject.offset, addObject.length);
+    addObject.name = string(newObjectKey);
+    mObjects.push_back(addObject);
+
+    return addObject;
+}
+
+
+int MetadataFile::updateMetadata(const char *filename)
+{
+    string metadataFilename = string(filename) + ".meta";
+    boost::property_tree::ptree jsontree;
+    boost::property_tree::ptree objs;
+    jsontree.put("version",mVersion);
+    jsontree.put("revision",mRevision);
+    for (std::vector<metadataObject>::const_iterator i = mObjects.begin(); i != mObjects.end(); ++i)
+    {
+        boost::property_tree::ptree object;
+        object.put("offset",i->offset);
+        object.put("length",i->length);
+        object.put("name",i->name);
+        objs.push_back(std::make_pair("", object));
+    }
+    jsontree.add_child("objects", objs);
+    write_json(metadataFilename, jsontree);
+}
+
+string MetadataFile::getNewKeyFromOldKey(const string &oldKey)
+{
+    boost::uuids::uuid u;
+    string ret(oldKey);
+    strcpy(&ret[0], boost::uuids::to_string(u).c_str());
+    return ret;
+}
+
+string MetadataFile::getNewKey(string sourceName, size_t offset, size_t length)
+{
+    boost::uuids::uuid u;
+    stringstream ss;
+
+    for (int i = 0; i < sourceName.length(); i++)
+    {
+        if (sourceName[i] == '/')
+        {
+            sourceName[i] = '-';
+        }
+    }
+
+    ss << u << "_" << offset << "_" << length << "_" << sourceName;
+    return ss.str();
+}
+
+void MetadataFile::printObjects()
+{
+    printf("Version: %i Revision: %i\n",mVersion,mRevision);
+    for (std::vector<metadataObject>::const_iterator i = mObjects.begin(); i != mObjects.end(); ++i)
+    {
+        printf("Name: %s Length: %lu Offset: %lu\n",i->name.c_str(),i->length,i->offset);
+    }
+}
+
+
+}
+
+
+

src/MetadataFile.h

@@ -0,0 +1,58 @@
+/*
+ * MetadataFile.h
+ */
+#ifndef METADATAFILE_H_
+#define METADATAFILE_H_
+
+#include "Config.h"
+#include "SMLogging.h"
+#include <string>
+#include <sys/types.h>
+#include <stdint.h>
+#include <vector>
+#include <iostream>
+#include <set>
+
+using namespace std;
+
+namespace storagemanager
+{
+
+struct metadataObject {
+    uint64_t offset;
+    uint64_t length;
+    string name;
+    bool operator < (const metadataObject &b) const { return offset < b.offset; }
+};
+
+class MetadataFile
+{
+    public:
+        MetadataFile();
+        MetadataFile(const char* filename);
+        ~MetadataFile();
+
+        void printObjects();
+        // returns the objects needed to update
+        vector<metadataObject> metadataRead(off_t offset, size_t length);
+        // updates the metadatafile with new object
+        int updateMetadata(const char *filename);
+        metadataObject addMetadataObject(const char *filename, size_t length);
+
+        // TBD: this may have to go; there may be no use case where only the uuid needs to change.
+        std::string getNewKeyFromOldKey(const std::string &oldKey);
+        std::string getNewKey(std::string sourceName, size_t offset, size_t length);
+
+    private:
+        Config *mpConfig;
+        SMLogging *mpLogger;
+        int mVersion;
+        int mRevision;
+        size_t mObjectSize;
+        //set<metadataObject> mObjects;
+        vector<metadataObject> mObjects;
+};
+
+}
+
+#endif /* METADATAFILE_H_ */

src/Replicator.cpp

@@ -0,0 +1,154 @@
+
+#include "Replicator.h"
+#include "IOCoordinator.h"
+#include "SMLogging.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/sendfile.h>
+#include <boost/filesystem.hpp>
+#include <boost/property_tree/json_parser.hpp>
+#include <boost/shared_array.hpp>
+#include <boost/format.hpp>
+#include <iostream>
+
+using namespace std;
+
+namespace
+{
+    storagemanager::Replicator *rep = NULL;
+    boost::mutex m;
+}
+namespace storagemanager
+{
+
+Replicator::Replicator()
+{
+}
+
+Replicator::~Replicator()
+{
+}
+
+Replicator * Replicator::get()
+{
+    if (rep)
+        return rep;
+    boost::mutex::scoped_lock s(m);
+    if (rep)
+        return rep;
+    rep = new Replicator();
+    return rep;
+}
+
+struct scoped_closer {
+    scoped_closer(int f) : fd(f) { }
+    ~scoped_closer() {
+        int s_errno = errno;
+        ::close(fd);
+        errno = s_errno;
+    }
+    int fd;
+};
+
+#define OPEN(name, mode) \
+    fd = ::open(name, mode, 0600); \
+    if (fd < 0) \
+        return fd; \
+    scoped_closer sc(fd);
+
+int Replicator::newObject(const char *filename, const uint8_t *data, size_t length )
+{
+    int fd, err;
+
+    OPEN(filename, O_WRONLY | O_CREAT);
+    size_t count = 0;
+    while (count < length) {
+        err = ::write(fd, &data[count], length - count);
+        if (err <= 0)
+            if (count > 0)   // return what was successfully written
+                return count;
+            else
+                return err;
+        count += err;
+    }
+
+    return count;
+}
+
+int Replicator::addJournalEntry(const char *filename, const uint8_t *data, off_t offset, size_t length)
+{
+    int fd, err;
+    uint64_t offlen[] = {offset,length};
+    size_t count = 0;
+    int version = 1;
+    string journalFilename = string(filename) + ".journal";
+    uint64_t thisEntryMaxOffset = (offset + length - 1);
+    if (!boost::filesystem::exists(journalFilename))
+    {
+        // create new journal file with header
+        OPEN(journalFilename.c_str(), O_WRONLY | O_CREAT);
+        string header = (boost::format("{ \"version\" : \"%03i\", \"max_offset\" : \"%011u\" }") % version % thisEntryMaxOffset).str();
+        err = ::write(fd, header.c_str(), header.length() + 1);
+        if (err <= 0)
+            return err;
+    }
+    else
+    {
+        // read the existing header and check if max_offset needs to be updated
+        OPEN(journalFilename.c_str(), O_RDWR);
+        boost::shared_array<char> headertxt = seekToEndOfHeader1(fd);
+        stringstream ss;
+        ss << headertxt.get();
+        boost::property_tree::ptree header;
+        boost::property_tree::json_parser::read_json(ss, header);
+        assert(header.get<int>("version") == 1);
+        uint64_t currentMaxOffset = header.get<uint64_t>("max_offset");
+        if (thisEntryMaxOffset > currentMaxOffset)
+        {
+            string header = (boost::format("{ \"version\" : \"%03i\", \"max_offset\" : \"%011u\" }") % version % thisEntryMaxOffset).str();
+            err = ::pwrite(fd, header.c_str(), header.length() + 1,0);
+            if (err <= 0)
+                return err;
+        }
+    }
+
+    OPEN(journalFilename.c_str(), O_WRONLY | O_APPEND);
+
+    err = ::write(fd, offlen, 16);
+    if (err <= 0)
+        return err;
+
+    while (count < length) {
+        err = ::write(fd, &data[count], length - count);
+        if (err <= 0)
+            if (count > 0)   // return what was successfully written
+                return count;
+            else
+                return err;
+        count += err;
+    }
+
+    return count;
+}
+
+int Replicator::remove(const char *filename, uint8_t flags)
+{
+    int ret = 0;
+    boost::filesystem::path p(filename);
+
+    try
+    {
+        boost::filesystem::remove_all(filename);
+    }
+    catch(boost::filesystem::filesystem_error &e)
+    {
+        errno = e.code().value();
+        ret = -1;
+    }
+    return ret;
+}
+
+}

src/Replicator.h

@@ -0,0 +1,33 @@
+#ifndef REPLICATOR_H_
+#define REPLICATOR_H_
+
+//#include "ThreadPool.h"
+#include <sys/types.h>
+#include <stdint.h>
+
+namespace storagemanager
+{
+
+//	64-bit offset
+//	64-bit length
+//	<length-bytes of data to write at specified offset>
+
+class Replicator
+{
+    public:
+        static Replicator *get();
+        virtual ~Replicator();
+
+        int addJournalEntry(const char *filename, const uint8_t *data, off_t offset, size_t length);
+        int newObject(const char *filename, const uint8_t *data, size_t length);
+        int remove(const char *key ,uint8_t flags);
+
+
+    private:
+        Replicator();
+        //ThreadPool threadPool;
+};
+
+}
+
+#endif

src/unit_tests.cpp

@@ -11,6 +11,8 @@
 #include "Config.h"
 #include "Cache.h"
 #include "LocalStorage.h"
+#include "MetadataFile.h"
+#include "Replicator.h"
 
 #include <iostream>
 #include <stdlib.h>
@@ -22,6 +24,9 @@
 #include <fcntl.h>
 #include <boost/filesystem.hpp>
 #include <boost/thread.hpp>
+#include <boost/format.hpp>
+#include <algorithm>
+#include <random>
 
 
 #undef NDEBUG
@@ -135,6 +140,59 @@ bool opentask()
     return true;
 }
 
+bool replicatorTest()
+{
+    Replicator *repli = Replicator::get();
+    int err,fd;
+    const char *newobject = "newobjectTest";
+    const char *newobjectJournal = "newobjectTest.journal";
+    uint8_t buf[1024];
+    uint8_t data[1024];
+    int version = 1;
+    uint64_t max_offset = 0;
+    memcpy(data,"1234567890",10);
+    string header = (boost::format("{ \"version\" : \"%03i\", \"max_offset\" : \"%011u\" }") % version % max_offset).str();
+    ::pwrite(fd, header.c_str(), header.length() + 1,0);
+
+    // test newObject
+    repli->newObject(newobject,data,10);
+    
+    //check file contents
+    fd = ::open(newobject, O_RDONLY);
+    err = ::read(fd, buf, 1024);
+    assert(err == 10);
+    buf[10] = 0;
+    assert(!strcmp("1234567890", (const char *) buf));
+    cout << "replicator newObject OK" << endl;
+    ::close(fd);
+
+    // test addJournalEntry
+    repli->addJournalEntry(newobject,data,0,10);
+
+    fd = ::open(newobjectJournal, O_RDONLY);
+    err = ::read(fd, buf, 1024);
+    assert(err == (header.length() + 1 + 16 + 10));
+    buf[err] = 0;
+    assert(!strcmp("1234567890", (const char *) buf + header.length() + 1 + 16));
+    cout << "replicator addJournalEntry OK" << endl;
+    ::close(fd);
+
+    repli->remove(newobject,0);
+    repli->remove(newobjectJournal,0);
+    assert(!boost::filesystem::exists(newobject));
+    cout << "replicator remove OK" << endl;
+    return true;
+}
+
+::vector<uint64_t> GenerateData(std::size_t bytes)
+{
+    assert(bytes % sizeof(uint64_t) == 0);
+    ::vector<uint64_t> data(bytes / sizeof(uint64_t));
+    ::iota(data.begin(), data.end(), 0);
+    ::shuffle(data.begin(), data.end(), std::mt19937{ std::random_device{}() });
+    return data;
+}
+
 bool writetask()
 {
     // make an empty file to write to
@@ -144,41 +202,46 @@ bool writetask()
     assert(fd > 0);
     scoped_closer f(fd);
  
-    uint8_t buf[1024];
-    sm_msg_header *hdr = (sm_msg_header *) buf;
-    write_cmd *cmd = (write_cmd *) &hdr[1];
-    uint8_t *data;
+    std::size_t writeSize = (10 * 1024);
+    std::vector<uint64_t> writeData = GenerateData(writeSize);
+    off_t nextOffset = 0;
 
-    cmd->opcode = WRITE;
-    cmd->offset = 0;
-    cmd->count = 9;
-    cmd->flen = 10;
-    memcpy(&cmd->filename, filename, cmd->flen);
-    data = (uint8_t *) &cmd->filename[cmd->flen];
-    memcpy(data, "123456789", cmd->count);
+    for (std::size_t size = writeSize; size <= (5 * writeSize); size += writeSize)
+    {
+        uint8_t buf[(1024 + writeSize)];
+        uint8_t *data;
+        sm_msg_header *hdr = (sm_msg_header *) buf;
+        write_cmd *cmd = (write_cmd *) &hdr[1];
+        cmd->opcode = WRITE;
+        cmd->offset = nextOffset;
+        cmd->count = writeSize;
+        cmd->flen = 10;
+        memcpy(&cmd->filename, filename, cmd->flen);
 
-    hdr->type = SM_MSG_START;
-    hdr->payloadLen = sizeof(*cmd) + cmd->flen + cmd->count;
+        data = (uint8_t *) &cmd->filename[cmd->flen];
+        memcpy(data, &writeData, writeSize);
     
-    WriteTask w(clientSock, hdr->payloadLen);
-    ::write(sessionSock, cmd, hdr->payloadLen);
-    w.run();
+        hdr->type = SM_MSG_START;
+        hdr->payloadLen = sizeof(*cmd) + cmd->flen + cmd->count;
 
-    // verify response
-    int err = ::recv(sessionSock, buf, 1024, MSG_DONTWAIT);
-    sm_response *resp = (sm_response *) buf;
-    assert(err == sizeof(*resp));
-    assert(resp->header.type == SM_MSG_START);
-    assert(resp->header.payloadLen == 4);
-    assert(resp->header.flags == 0);
-    assert(resp->returnCode == 9);
+        WriteTask w(clientSock, hdr->payloadLen);
+        ::write(sessionSock, cmd, hdr->payloadLen);
+        w.run();
 
-    //check file contents
-    err = ::read(fd, buf, 1024);
-    assert(err == 9);
-    buf[9] = 0;
-    assert(!strcmp("123456789", (const char *) buf));
-    ::unlink(filename);
+        // verify response
+        int err = ::recv(sessionSock, buf, 1024, MSG_DONTWAIT);
+        sm_response *resp = (sm_response *) buf;
+        assert(err == sizeof(*resp));
+        assert(resp->header.type == SM_MSG_START);
+        assert(resp->header.payloadLen == 4);
+        assert(resp->header.flags == 0);
+        assert(resp->returnCode == writeSize);
+        nextOffset += (writeSize);
+    }
+    // This leaves behind object journal and metadata files currently
+    
+    MetadataFile mdf("./writetest1");
+    mdf.printObjects();
     cout << "write task OK" << endl;
     return true;
 }
@@ -612,10 +675,10 @@ int main()
     listdirtask();
     pingtask();
     copytask();
-    
     localstorageTest1();
     cacheTest1();
     mergeJournalTest();
+    replicatorTest();
 
     return 0;
 }