Mercurial > hg > orthanc

changeset 2976:cb5d75143da0

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Asynchronous generation of ZIP archives and DICOM medias
author Sebastien Jodogne <s.jodogne@gmail.com>
date Thu, 06 Dec 2018 12:23:46 +0100
parents eea66afed0db
children ee0b2c5ad49b
files Core/Cache/SharedArchive.cpp Core/Cache/SharedArchive.h Core/Enumerations.cpp Core/Enumerations.h Core/JobsEngine/IJob.h Core/JobsEngine/JobsRegistry.cpp Core/JobsEngine/JobsRegistry.h Core/JobsEngine/Operations/SequenceOfOperationsJob.h Core/JobsEngine/SetOfCommandsJob.h NEWS OrthancServer/OrthancRestApi/OrthancRestApi.cpp OrthancServer/OrthancRestApi/OrthancRestApi.h OrthancServer/OrthancRestApi/OrthancRestArchive.cpp OrthancServer/OrthancRestApi/OrthancRestSystem.cpp OrthancServer/ServerContext.h OrthancServer/ServerJobs/ArchiveJob.cpp OrthancServer/ServerJobs/ArchiveJob.h Plugins/Engine/PluginsJob.h UnitTestsSources/MemoryCacheTests.cpp UnitTestsSources/MultiThreadingTests.cpp
diffstat 20 files changed, 329 insertions(+), 64 deletions(-) [+]
line wrap: on
line diff
--- a/Core/Cache/SharedArchive.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/Cache/SharedArchive.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -47,6 +47,8 @@
     {
       delete it->second;
       archive_.erase(it);
+
+      lru_.Invalidate(id);
     }
   }
 
@@ -59,7 +61,7 @@
 
     if (it == that.archive_.end())
     {
-      throw OrthancException(ErrorCode_InexistentItem);
+      item_ = NULL;
     }
     else
     {
@@ -69,6 +71,20 @@
   }
 
 
+  IDynamicObject& SharedArchive::Accessor::GetItem() const
+  {
+    if (item_ == NULL)
+    {
+      // "IsValid()" should have been called
+      throw OrthancException(ErrorCode_BadSequenceOfCalls);
+    }
+    else
+    {
+      return *item_;
+    }
+  }  
+
+
   SharedArchive::SharedArchive(size_t maxSize) : 
     maxSize_(maxSize)
   {
@@ -96,12 +112,12 @@
     if (archive_.size() == maxSize_)
     {
       // The quota has been reached, remove the oldest element
-      std::string oldest = lru_.RemoveOldest();
-      RemoveInternal(oldest);
+      RemoveInternal(lru_.GetOldest());
     }
 
     std::string id = Toolbox::GenerateUuid();
     RemoveInternal(id);  // Should never be useful because of UUID
+
     archive_[id] = obj;
     lru_.Add(id);
 
@@ -113,7 +129,6 @@
   {
     boost::mutex::scoped_lock lock(mutex_);
     RemoveInternal(id);      
-    lru_.Invalidate(id);
   }
 
 
@@ -121,14 +136,14 @@
   {
     items.clear();
 
-    boost::mutex::scoped_lock lock(mutex_);
+    {
+      boost::mutex::scoped_lock lock(mutex_);
 
-    for (Archive::const_iterator it = archive_.begin();
-         it != archive_.end(); ++it)
-    {
-      items.push_back(it->first);
+      for (Archive::const_iterator it = archive_.begin();
+           it != archive_.end(); ++it)
+      {
+        items.push_back(it->first);
+      }
     }
   }
 }
-
-
--- a/Core/Cache/SharedArchive.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/Cache/SharedArchive.h	Thu Dec 06 12:23:46 2018 +0100
@@ -72,10 +72,12 @@
       Accessor(SharedArchive& that,
                const std::string& id);
 
-      IDynamicObject& GetItem() const
+      bool IsValid() const
       {
-        return *item_;
-      }      
+        return item_ != NULL;
+      }
+      
+      IDynamicObject& GetItem() const;
     };
 
 
--- a/Core/Enumerations.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/Enumerations.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -54,6 +54,7 @@
   static const char* const MIME_PLAIN_TEXT = "text/plain";
   static const char* const MIME_WEB_ASSEMBLY = "application/wasm";
   static const char* const MIME_XML_2 = "text/xml";
+  static const char* const MIME_ZIP = "application/zip";
 
   // This function is autogenerated by the script
   // "Resources/GenerateErrorCodes.py"
@@ -1084,6 +1085,9 @@
       case MimeType_Gif:
         return MIME_GIF;
                 
+      case MimeType_Zip:
+        return MIME_ZIP;
+                
       default:
         throw OrthancException(ErrorCode_ParameterOutOfRange);
     }
@@ -1672,6 +1676,10 @@
     {
       return MimeType_Gif;
     }
+    else if (mime == MIME_ZIP)
+    {
+      return MimeType_Zip;
+    }
     else
     {
       throw OrthancException(ErrorCode_ParameterOutOfRange);
--- a/Core/Enumerations.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/Enumerations.h	Thu Dec 06 12:23:46 2018 +0100
@@ -100,7 +100,8 @@
     MimeType_JavaScript,
     MimeType_Css,
     MimeType_WebAssembly,
-    MimeType_Gif
+    MimeType_Gif,
+    MimeType_Zip
   };
 
   
--- a/Core/JobsEngine/IJob.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/JobsEngine/IJob.h	Thu Dec 06 12:23:46 2018 +0100
@@ -65,5 +65,11 @@
     virtual void GetPublicContent(Json::Value& value) = 0;
 
     virtual bool Serialize(Json::Value& value) = 0;
+
+    // This function can only be called if the job has reached its
+    // "success" state
+    virtual bool GetOutput(std::string& output,
+                           MimeType& mime,
+                           const std::string& key) = 0;
   };
 }
--- a/Core/JobsEngine/JobsRegistry.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/JobsEngine/JobsRegistry.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -263,7 +263,7 @@
         // as a "RunningJob" instance is running. We do not use a
         // mutex at the "JobHandler" level, as serialization would be
         // blocked while a step in the job is running. Instead, we
-        // save a snapshot of the serialized job.
+        // save a snapshot of the serialized job. (*)
 
         if (lastStatus_.HasSerialized())
         {
@@ -631,6 +631,36 @@
   }
 
 
+  bool JobsRegistry::GetJobOutput(std::string& output,
+                                  MimeType& mime,
+                                  const std::string& job,
+                                  const std::string& key)
+  {
+    boost::mutex::scoped_lock lock(mutex_);
+    CheckInvariants();
+
+    JobsIndex::const_iterator found = jobsIndex_.find(job);
+
+    if (found == jobsIndex_.end())
+    {
+      return false;
+    }
+    else
+    {
+      const JobHandler& handler = *found->second;
+
+      if (handler.GetState() == JobState_Success)
+      {
+        return handler.GetJob().GetOutput(output, mime, key);
+      }
+      else
+      {
+        return false;
+      }
+    }
+  }
+
+
   void JobsRegistry::SubmitInternal(std::string& id,
                                     JobHandler* handler)
   {
--- a/Core/JobsEngine/JobsRegistry.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/JobsEngine/JobsRegistry.h	Thu Dec 06 12:23:46 2018 +0100
@@ -161,6 +161,11 @@
     bool GetJobInfo(JobInfo& target,
                     const std::string& id);
 
+    bool GetJobOutput(std::string& output,
+                      MimeType& mime,
+                      const std::string& job,
+                      const std::string& key);
+
     void Serialize(Json::Value& target);
     
     void Submit(std::string& id,
--- a/Core/JobsEngine/Operations/SequenceOfOperationsJob.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/JobsEngine/Operations/SequenceOfOperationsJob.h	Thu Dec 06 12:23:46 2018 +0100
@@ -147,6 +147,13 @@
 
     virtual bool Serialize(Json::Value& value);
 
+    virtual bool GetOutput(std::string& output,
+                           MimeType& mime,
+                           const std::string& key)
+    {
+      return false;
+    }
+
     void AwakeTrailingSleep()
     {
       operationAdded_.notify_one();
--- a/Core/JobsEngine/SetOfCommandsJob.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/Core/JobsEngine/SetOfCommandsJob.h	Thu Dec 06 12:23:46 2018 +0100
@@ -131,5 +131,12 @@
     virtual void GetPublicContent(Json::Value& value);
     
     virtual bool Serialize(Json::Value& target);
+
+    virtual bool GetOutput(std::string& output,
+                           MimeType& mime,
+                           const std::string& key)
+    {
+      return false;
+    }
   };
 }
--- a/NEWS	Thu Dec 06 10:10:58 2018 +0100
+++ b/NEWS	Thu Dec 06 12:23:46 2018 +0100
@@ -21,6 +21,7 @@
 --------
 
 * API Version has been upgraded to 1.2
+* Asynchronous generation of ZIP archives and DICOM medias
 * New URI: "/studies/.../merge" to merge a study
 * New URI: "/studies/.../split" to split a study
 * POST-ing a DICOM file to "/instances" also answers the patient/study/series ID
--- a/OrthancServer/OrthancRestApi/OrthancRestApi.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/OrthancServer/OrthancRestApi/OrthancRestApi.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -211,10 +211,11 @@
   }
   
 
-  void OrthancRestApi::SubmitGenericJob(RestApiPostCall& call,
+  void OrthancRestApi::SubmitGenericJob(RestApiOutput& output,
+                                        ServerContext& context,
                                         IJob* job,
-                                        bool isDefaultSynchronous,
-                                        const Json::Value& body) const
+                                        bool synchronous,
+                                        int priority)
   {
     std::auto_ptr<IJob> raii(job);
     
@@ -223,41 +224,55 @@
       throw OrthancException(ErrorCode_NullPointer);
     }
 
-    if (body.type() != Json::objectValue)
-    {
-      throw OrthancException(ErrorCode_BadFileFormat);
-    }
-
-    if (IsSynchronousJobRequest(isDefaultSynchronous, body))
+    if (synchronous)
     {
       Json::Value successContent;
-      if (context_.GetJobsEngine().GetRegistry().SubmitAndWait
-          (successContent, raii.release(), GetJobRequestPriority(body)))
+      if (context.GetJobsEngine().GetRegistry().SubmitAndWait
+          (successContent, raii.release(), priority))
       {
         // Success in synchronous execution
-        call.GetOutput().AnswerJson(successContent);
+        output.AnswerJson(successContent);
       }
       else
       {
         // Error during synchronous execution
-        call.GetOutput().SignalError(HttpStatus_500_InternalServerError);
+        output.SignalError(HttpStatus_500_InternalServerError);
       }
     }
     else
     {
       // Asynchronous mode: Submit the job, but don't wait for its completion
       std::string id;
-      context_.GetJobsEngine().GetRegistry().Submit
-        (id, raii.release(), GetJobRequestPriority(body));
+      context.GetJobsEngine().GetRegistry().Submit
+        (id, raii.release(), priority);
 
       Json::Value v;
       v["ID"] = id;
       v["Path"] = "/jobs/" + id;
-      call.GetOutput().AnswerJson(v);
+      output.AnswerJson(v);
     }
   }
 
   
+  void OrthancRestApi::SubmitGenericJob(RestApiPostCall& call,
+                                        IJob* job,
+                                        bool isDefaultSynchronous,
+                                        const Json::Value& body) const
+  {
+    std::auto_ptr<IJob> raii(job);
+
+    if (body.type() != Json::objectValue)
+    {
+      throw OrthancException(ErrorCode_BadFileFormat);
+    }
+
+    bool synchronous = IsSynchronousJobRequest(isDefaultSynchronous, body);
+    int priority = GetJobRequestPriority(body);
+
+    SubmitGenericJob(call.GetOutput(), context_, raii.release(), synchronous, priority);
+  }
+
+  
   void OrthancRestApi::SubmitCommandsJob(RestApiPostCall& call,
                                          SetOfCommandsJob* job,
                                          bool isDefaultSynchronous,
@@ -265,11 +280,6 @@
   {
     std::auto_ptr<SetOfCommandsJob> raii(job);
     
-    if (job == NULL)
-    {
-      throw OrthancException(ErrorCode_NullPointer);
-    }
-
     if (body.type() != Json::objectValue)
     {
       throw OrthancException(ErrorCode_BadFileFormat);
--- a/OrthancServer/OrthancRestApi/OrthancRestApi.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/OrthancServer/OrthancRestApi/OrthancRestApi.h	Thu Dec 06 12:23:46 2018 +0100
@@ -108,6 +108,12 @@
     
     static unsigned int GetJobRequestPriority(const Json::Value& body);
     
+    static void SubmitGenericJob(RestApiOutput& output,
+                                 ServerContext& context,
+                                 IJob* job,
+                                 bool synchronous,
+                                 int priority);
+    
     void SubmitGenericJob(RestApiPostCall& call,
                           IJob* job,
                           bool isDefaultSynchronous,
--- a/OrthancServer/OrthancRestApi/OrthancRestArchive.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/OrthancServer/OrthancRestApi/OrthancRestArchive.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -155,7 +155,7 @@
     }
     else
     {
-      throw OrthancException(ErrorCode_NotImplemented);
+      OrthancRestApi::SubmitGenericJob(output, context, job.release(), false, priority);
     }
   }
 
--- a/OrthancServer/OrthancRestApi/OrthancRestSystem.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/OrthancServer/OrthancRestApi/OrthancRestSystem.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -325,6 +325,27 @@
   }
 
 
+  static void GetJobOutput(RestApiGetCall& call)
+  {
+    std::string job = call.GetUriComponent("id", "");
+    std::string key = call.GetUriComponent("key", "");
+
+    std::string value;
+    MimeType mime;
+    
+    if (OrthancRestApi::GetContext(call).GetJobsEngine().
+        GetRegistry().GetJobOutput(value, mime, job, key))
+    {
+      call.GetOutput().AnswerBuffer(value, mime);
+    }
+    else
+    {
+      throw OrthancException(ErrorCode_InexistentItem,
+                             "Job has no such output: " + key);
+    }
+  }
+
+
   enum JobAction
   {
     JobAction_Cancel,
@@ -392,5 +413,6 @@
     Register("/jobs/{id}/pause", ApplyJobAction<JobAction_Pause>);
     Register("/jobs/{id}/resubmit", ApplyJobAction<JobAction_Resubmit>);
     Register("/jobs/{id}/resume", ApplyJobAction<JobAction_Resume>);
+    Register("/jobs/{id}/{key}", GetJobOutput);
   }
 }
--- a/OrthancServer/ServerContext.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/OrthancServer/ServerContext.h	Thu Dec 06 12:23:46 2018 +0100
@@ -164,11 +164,13 @@
     LuaScripting mainLua_;
     LuaScripting filterLua_;
     LuaServerListener  luaListener_;
-
+    std::auto_ptr<SharedArchive>  mediaArchive_;
+    
     // The "JobsEngine" must be *after* "LuaScripting", as
     // "LuaScripting" embeds "LuaJobManager" that registers as an
     // observer to "SequenceOfOperationsJob", whose lifetime
-    // corresponds to that of "JobsEngine"
+    // corresponds to that of "JobsEngine". It must also be after
+    // "mediaArchive_", as jobs might access this archive.
     JobsEngine jobsEngine_;
     
 #if ORTHANC_ENABLE_PLUGINS == 1
@@ -189,8 +191,6 @@
     std::string defaultLocalAet_;
     OrthancHttpHandler  httpHandler_;
 
-    std::auto_ptr<SharedArchive>  mediaArchive_;
-    
   public:
     class DicomCacheLocker : public boost::noncopyable
     {
--- a/OrthancServer/ServerJobs/ArchiveJob.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/OrthancServer/ServerJobs/ArchiveJob.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -47,7 +47,12 @@
 
 static const uint64_t MEGA_BYTES = 1024 * 1024;
 static const uint64_t GIGA_BYTES = 1024 * 1024 * 1024;
-static const char* MEDIA_IMAGES_FOLDER = "IMAGES"; 
+
+static const char* const MEDIA_IMAGES_FOLDER = "IMAGES"; 
+static const char* const KEY_DESCRIPTION = "Description";
+static const char* const KEY_INSTANCES_COUNT = "InstancesCount";
+static const char* const KEY_UNCOMPRESSED_SIZE_MB = "UncompressedSizeMB";
+
 
 namespace Orthanc
 {
@@ -791,6 +796,15 @@
   {
   }
 
+  
+  ArchiveJob::~ArchiveJob()
+  {
+    if (!mediaArchiveId_.empty())
+    {
+      context_.GetMediaArchive().Remove(mediaArchiveId_);
+    }
+  }
+
 
   void ArchiveJob::SetSynchronousTarget(boost::shared_ptr<TemporaryFile>& target)
   {
@@ -798,7 +812,9 @@
     {
       throw OrthancException(ErrorCode_NullPointer);
     }
-    else if (synchronousTarget_.get() != NULL)
+    else if (writer_.get() != NULL ||  // Already started
+             synchronousTarget_.get() != NULL ||
+             asynchronousTarget_.get() != NULL)
     {
       throw OrthancException(ErrorCode_BadSequenceOfCalls);
     }
@@ -809,15 +825,30 @@
   }
 
 
+  void ArchiveJob::SetDescription(const std::string& description)
+  {
+    if (writer_.get() != NULL)   // Already started
+    {
+      throw OrthancException(ErrorCode_BadSequenceOfCalls);
+    }
+    else
+    {
+      description_ = description;
+    }
+  }
+
+  
   void ArchiveJob::AddResource(const std::string& publicId)
   {
     if (writer_.get() != NULL)   // Already started
     {
       throw OrthancException(ErrorCode_BadSequenceOfCalls);
     }
-        
-    ResourceIdentifiers resource(context_.GetIndex(), publicId);
-    archive_->Add(context_.GetIndex(), resource);
+    else
+    {
+      ResourceIdentifiers resource(context_.GetIndex(), publicId);
+      archive_->Add(context_.GetIndex(), resource);
+    }
   }
 
   
@@ -830,9 +861,16 @@
   
   void ArchiveJob::Start()
   {
+    TemporaryFile* target = NULL;
+    
     if (synchronousTarget_.get() == NULL)
     {
-      throw OrthancException(ErrorCode_BadSequenceOfCalls);
+      asynchronousTarget_.reset(new TemporaryFile);
+      target = asynchronousTarget_.get();
+    }
+    else
+    {
+      target = synchronousTarget_.get();
     }
     
     if (writer_.get() != NULL)
@@ -840,19 +878,59 @@
       throw OrthancException(ErrorCode_BadSequenceOfCalls);
     }
 
-    writer_.reset(new ZipWriterIterator(*synchronousTarget_, context_, *archive_,
+    writer_.reset(new ZipWriterIterator(*target, context_, *archive_,
                                         isMedia_, enableExtendedSopClass_));
 
     instancesCount_ = writer_->GetInstancesCount();
     uncompressedSize_ = writer_->GetUncompressedSize();
   }
 
+
+
+  namespace
+  {
+    class DynamicTemporaryFile : public IDynamicObject
+    {
+    private:
+      std::auto_ptr<TemporaryFile>   file_;
+
+    public:
+      DynamicTemporaryFile(TemporaryFile* f) : file_(f)
+      {
+        if (f == NULL)
+        {
+          throw OrthancException(ErrorCode_NullPointer);
+        }
+      }
+
+      const TemporaryFile& GetFile() const
+      {
+        assert(file_.get() != NULL);
+        return *file_;
+      }
+    };
+  }
   
+
+  void ArchiveJob::FinalizeTarget()
+  {
+    writer_.reset();  // Flush all the results
+
+    if (asynchronousTarget_.get() != NULL)
+    {
+      // Asynchronous behavior: Move the resulting file into the media archive
+      mediaArchiveId_ = context_.GetMediaArchive().Add(
+        new DynamicTemporaryFile(asynchronousTarget_.release()));
+    }
+  }
+    
+
   JobStepResult ArchiveJob::Step()
   {
     assert(writer_.get() != NULL);
 
-    if (synchronousTarget_.unique())
+    if (synchronousTarget_.get() != NULL &&
+        synchronousTarget_.unique())
     {
       LOG(WARNING) << "A client has disconnected while creating an archive";
       return JobStepResult::Failure(ErrorCode_NetworkProtocol);          
@@ -860,7 +938,7 @@
         
     if (writer_->GetStepsCount() == 0)
     {
-      writer_.reset();  // Flush all the results
+      FinalizeTarget();
       return JobStepResult::Success();
     }
     else
@@ -871,7 +949,7 @@
 
       if (currentStep_ == writer_->GetStepsCount())
       {
-        writer_.reset();  // Flush all the results
+        FinalizeTarget();
         return JobStepResult::Success();
       }
       else
@@ -909,12 +987,41 @@
     }
   }
 
-    
+
   void ArchiveJob::GetPublicContent(Json::Value& value)
   {
-    value["Description"] = description_;
-    value["InstancesCount"] = instancesCount_;
-    value["UncompressedSizeMB"] =
+    value = Json::objectValue;
+    value[KEY_DESCRIPTION] = description_;
+    value[KEY_INSTANCES_COUNT] = instancesCount_;
+    value[KEY_UNCOMPRESSED_SIZE_MB] =
       static_cast<unsigned int>(uncompressedSize_ / MEGA_BYTES);
   }
+
+
+  bool ArchiveJob::GetOutput(std::string& output,
+                             MimeType& mime,
+                             const std::string& key)
+  {   
+    if (key == "archive" &&
+        !mediaArchiveId_.empty())
+    {
+      SharedArchive::Accessor accessor(context_.GetMediaArchive(), mediaArchiveId_);
+
+      if (accessor.IsValid())
+      {
+        const DynamicTemporaryFile& f = dynamic_cast<DynamicTemporaryFile&>(accessor.GetItem());
+        f.GetFile().Read(output);
+        mime = MimeType_Zip;
+        return true;
+      }
+      else
+      {
+        return false;
+      }
+    }    
+    else
+    {
+      return false;
+    }
+  }
 }
--- a/OrthancServer/ServerJobs/ArchiveJob.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/OrthancServer/ServerJobs/ArchiveJob.h	Thu Dec 06 12:23:46 2018 +0100
@@ -51,6 +51,7 @@
     class ZipWriterIterator;
     
     boost::shared_ptr<TemporaryFile>      synchronousTarget_;
+    std::auto_ptr<TemporaryFile>          asynchronousTarget_;
     ServerContext&                        context_;
     boost::shared_ptr<ArchiveIndex>       archive_;
     bool                                  isMedia_;
@@ -61,18 +62,20 @@
     size_t                                currentStep_;
     unsigned int                          instancesCount_;
     uint64_t                              uncompressedSize_;
+    std::string                           mediaArchiveId_;
 
+    void FinalizeTarget();
+    
   public:
     ArchiveJob(ServerContext& context,
                bool isMedia,
                bool enableExtendedSopClass);
-
-    void SetSynchronousTarget(boost::shared_ptr<TemporaryFile>& synchronousTarget);
+    
+    virtual ~ArchiveJob();
     
-    void SetDescription(const std::string& description)
-    {
-      description_ = description;
-    }
+    void SetSynchronousTarget(boost::shared_ptr<TemporaryFile>& synchronousTarget);
+
+    void SetDescription(const std::string& description);
 
     const std::string& GetDescription() const
     {
@@ -101,5 +104,9 @@
     {
       return false;  // Cannot serialize this kind of job
     }
+
+    virtual bool GetOutput(std::string& output,
+                           MimeType& mime,
+                           const std::string& key);
   };
 }
--- a/Plugins/Engine/PluginsJob.h	Thu Dec 06 10:10:58 2018 +0100
+++ b/Plugins/Engine/PluginsJob.h	Thu Dec 06 12:23:46 2018 +0100
@@ -71,6 +71,14 @@
     virtual void GetPublicContent(Json::Value& value);
 
     virtual bool Serialize(Json::Value& value);
+
+    virtual bool GetOutput(std::string& output,
+                           MimeType& mime,
+                           const std::string& key)
+    {
+      // TODO
+      return false;
+    }
   };
 }
 
--- a/UnitTestsSources/MemoryCacheTests.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/UnitTestsSources/MemoryCacheTests.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -261,9 +261,25 @@
   for (int i = 1; i < 100; i++)
   {
     a.Add(new S("Item " + boost::lexical_cast<std::string>(i)));
+    
     // Continuously protect the two first items
-    try { Orthanc::SharedArchive::Accessor(a, first);  } catch (Orthanc::OrthancException&) {}
-    try { Orthanc::SharedArchive::Accessor(a, second); } catch (Orthanc::OrthancException&) {}
+    {
+      Orthanc::SharedArchive::Accessor accessor(a, first);
+      ASSERT_TRUE(accessor.IsValid());
+      ASSERT_EQ("First item", dynamic_cast<S&>(accessor.GetItem()).GetValue());
+    }
+
+    {
+      Orthanc::SharedArchive::Accessor accessor(a, second);
+      ASSERT_TRUE(accessor.IsValid());
+      ASSERT_EQ("Second item", dynamic_cast<S&>(accessor.GetItem()).GetValue());
+    }
+
+    {
+      Orthanc::SharedArchive::Accessor accessor(a, "nope");
+      ASSERT_FALSE(accessor.IsValid());
+      ASSERT_THROW(accessor.GetItem(), Orthanc::OrthancException);
+    }
   }
 
   std::list<std::string> i;
--- a/UnitTestsSources/MultiThreadingTests.cpp	Thu Dec 06 10:10:58 2018 +0100
+++ b/UnitTestsSources/MultiThreadingTests.cpp	Thu Dec 06 12:23:46 2018 +0100
@@ -143,6 +143,13 @@
     {
       value["hello"] = "world";
     }
+
+    virtual bool GetOutput(std::string& output,
+                           MimeType& mime,
+                           const std::string& key) ORTHANC_OVERRIDE
+    {
+      return false;
+    }
   };