--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancFramework/Sources/JobsEngine/JobsRegistry.h	Wed Jun 10 20:30:34 2020 +0200
@@ -0,0 +1,255 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders of this
+ * program give permission to link the code of its release with the
+ * OpenSSL project's "OpenSSL" library (or with modified versions of it
+ * that use the same license as the "OpenSSL" library), and distribute
+ * the linked executables. You must obey the GNU General Public License
+ * in all respects for all of the code used other than "OpenSSL". If you
+ * modify file(s) with this exception, you may extend this exception to
+ * your version of the file(s), but you are not obligated to do so. If
+ * you do not wish to do so, delete this exception statement from your
+ * version. If you delete this exception statement from all source files
+ * in the program, then also delete it here.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#pragma once
+
+#if !defined(ORTHANC_SANDBOXED)
+#  error The macro ORTHANC_SANDBOXED must be defined
+#endif
+
+#if ORTHANC_SANDBOXED == 1
+#  error The job engine cannot be used in sandboxed environments
+#endif
+
+#include "JobInfo.h"
+#include "IJobUnserializer.h"
+
+#include <list>
+#include <set>
+#include <queue>
+#include <boost/thread/mutex.hpp>
+#include <boost/thread/condition_variable.hpp>
+
+namespace Orthanc
+{
+  // This class handles the state machine of the jobs engine
+  class JobsRegistry : public boost::noncopyable
+  {
+  public:
+    class IObserver : public boost::noncopyable
+    {
+    public:
+      virtual ~IObserver()
+      {
+      }
+
+      virtual void SignalJobSubmitted(const std::string& jobId) = 0;
+
+      virtual void SignalJobSuccess(const std::string& jobId) = 0;
+
+      virtual void SignalJobFailure(const std::string& jobId) = 0;
+    };
+
+  private:
+    enum CompletedReason
+    {
+      CompletedReason_Success,
+      CompletedReason_Failure,
+      CompletedReason_Canceled
+    };
+
+    class JobHandler;
+
+    struct PriorityComparator
+    {
+      bool operator() (JobHandler*& a,
+                       JobHandler*& b) const;
+    };
+
+    typedef std::map<std::string, JobHandler*>              JobsIndex;
+    typedef std::list<JobHandler*>                          CompletedJobs;
+    typedef std::set<JobHandler*>                           RetryJobs;
+    typedef std::priority_queue<JobHandler*,
+                                std::vector<JobHandler*>,   // Could be a "std::deque"
+                                PriorityComparator>         PendingJobs;
+
+    boost::mutex               mutex_;
+    JobsIndex                  jobsIndex_;
+    PendingJobs                pendingJobs_;
+    CompletedJobs              completedJobs_;
+    RetryJobs                  retryJobs_;
+
+    boost::condition_variable  pendingJobAvailable_;
+    boost::condition_variable  someJobComplete_;
+    size_t                     maxCompletedJobs_;
+
+    IObserver*                 observer_;
+
+
+#ifndef NDEBUG
+    bool IsPendingJob(const JobHandler& job) const;
+
+    bool IsCompletedJob(JobHandler& job) const;
+
+    bool IsRetryJob(JobHandler& job) const;
+#endif
+
+    void CheckInvariants() const;
+
+    void ForgetOldCompletedJobs();
+
+    void SetCompletedJob(JobHandler& job,
+                         bool success);
+
+    void MarkRunningAsCompleted(JobHandler& job,
+                                CompletedReason reason);
+
+    void MarkRunningAsRetry(JobHandler& job,
+                            unsigned int timeout);
+
+    void MarkRunningAsPaused(JobHandler& job);
+
+    bool GetStateInternal(JobState& state,
+                          const std::string& id);
+
+    void RemovePendingJob(const std::string& id);
+
+    void RemoveRetryJob(JobHandler* handler);
+
+    void SubmitInternal(std::string& id,
+                        JobHandler* handler);
+
+  public:
+    JobsRegistry(size_t maxCompletedJobs) :
+      maxCompletedJobs_(maxCompletedJobs),
+      observer_(NULL)
+    {
+    }
+
+    JobsRegistry(IJobUnserializer& unserializer,
+                 const Json::Value& s,
+                 size_t maxCompletedJobs);
+
+    ~JobsRegistry();
+
+    void SetMaxCompletedJobs(size_t i);
+
+    size_t GetMaxCompletedJobs();
+
+    void ListJobs(std::set<std::string>& target);
+
+    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,
+                IJob* job,        // Takes ownership
+                int priority);
+
+    void Submit(IJob* job,        // Takes ownership
+                int priority);
+
+    void SubmitAndWait(Json::Value& successContent,
+                       IJob* job,        // Takes ownership
+                       int priority);
+
+    bool SetPriority(const std::string& id,
+                     int priority);
+
+    bool Pause(const std::string& id);
+
+    bool Resume(const std::string& id);
+
+    bool Resubmit(const std::string& id);
+
+    bool Cancel(const std::string& id);
+
+    void ScheduleRetries();
+
+    bool GetState(JobState& state,
+                  const std::string& id);
+
+    void SetObserver(IObserver& observer);
+
+    void ResetObserver();
+
+    void GetStatistics(unsigned int& pending,
+                       unsigned int& running,
+                       unsigned int& success,
+                       unsigned int& errors);
+
+    class RunningJob : public boost::noncopyable
+    {
+    private:
+      JobsRegistry&  registry_;
+      JobHandler*    handler_;  // Can only be accessed if the
+                                // registry mutex is locked!
+      IJob*          job_;  // Will by design be in mutual exclusion,
+                            // because only one RunningJob can be
+                            // executed at a time on a JobHandler
+
+      std::string    id_;
+      int            priority_;
+      JobState       targetState_;
+      unsigned int   targetRetryTimeout_;
+      bool           canceled_;
+
+    public:
+      RunningJob(JobsRegistry& registry,
+                 unsigned int timeout);
+
+      ~RunningJob();
+
+      bool IsValid() const;
+
+      const std::string& GetId() const;
+
+      int GetPriority() const;
+
+      IJob& GetJob();
+
+      bool IsPauseScheduled();
+
+      bool IsCancelScheduled();
+
+      void MarkSuccess();
+
+      void MarkFailure();
+
+      void MarkPause();
+
+      void MarkCanceled();
+
+      void MarkRetry(unsigned int timeout);
+
+      void UpdateStatus(ErrorCode code,
+                        const std::string& details);
+    };
+  };
+}