--- a/OrthancServer/Sources/ServerContext.cpp	Wed Sep 04 10:54:00 2024 +0200
+++ b/OrthancServer/Sources/ServerContext.cpp	Wed Oct 09 11:01:11 2024 +0200
@@ -355,8 +355,9 @@
   ServerContext::ServerContext(IDatabaseWrapper& database,
                                IStorageArea& area,
                                bool unitTesting,
-                               size_t maxCompletedJobs) :
-    index_(*this, database, (unitTesting ? 20 : 500)),
+                               size_t maxCompletedJobs,
+                               bool readOnly) :
+    index_(*this, database, (unitTesting ? 20 : 500), readOnly),
     area_(area),
     compressionEnabled_(false),
     storeMD5_(true),
@@ -382,6 +383,7 @@
     ingestTranscodingOfUncompressed_(true),
     ingestTranscodingOfCompressed_(true),
     preferredTransferSyntax_(DicomTransferSyntax_LittleEndianExplicit),
+    readOnly_(readOnly),
     deidentifyLogs_(false),
     serverStartTimeUtc_(boost::posix_time::second_clock::universal_time())
   {
@@ -398,7 +400,14 @@
           new SharedArchive(lock.GetConfiguration().GetUnsignedIntegerParameter("MediaArchiveSize", 1)));
         defaultLocalAet_ = lock.GetConfiguration().GetOrthancAET();
         jobsEngine_.SetWorkersCount(lock.GetConfiguration().GetUnsignedIntegerParameter("ConcurrentJobs", 2));
+
         saveJobs_ = lock.GetConfiguration().GetBooleanParameter("SaveJobs", true);
+        if (readOnly_ && saveJobs_)
+        {
+          LOG(WARNING) << "READ-ONLY SYSTEM: SaveJobs = true is incompatible with a ReadOnly system, ignoring this configuration";
+          saveJobs_ = false;
+        }
+
         metricsRegistry_->SetEnabled(lock.GetConfiguration().GetBooleanParameter("MetricsEnabled", true));
 
         // New configuration options in Orthanc 1.5.1
@@ -1030,11 +1039,91 @@
     dicomAsJson["7fe0,0010"] = pixelData;
   }
 
+
+  static bool LookupMetadata(std::string& value,
+                             MetadataType key,
+                             const std::map<MetadataType, std::string>& instanceMetadata)
+  {
+    std::map<MetadataType, std::string>::const_iterator found = instanceMetadata.find(key);
+
+    if (found == instanceMetadata.end())
+    {
+      return false;
+    }
+    else
+    {
+      value = found->second;
+      return true;
+    }
+  }
+
+
+  static bool LookupAttachment(FileInfo& target,
+                               FileContentType type,
+                               const std::map<FileContentType, FileInfo>& attachments)
+  {
+    std::map<FileContentType, FileInfo>::const_iterator found = attachments.find(type);
+
+    if (found == attachments.end())
+    {
+      return false;
+    }
+    else if (found->second.GetContentType() == type)
+    {
+      target = found->second;
+      return true;
+    }
+    else
+    {
+      throw OrthancException(ErrorCode_DatabasePlugin);
+    }
+  }
+
   
   void ServerContext::ReadDicomAsJson(Json::Value& result,
                                       const std::string& instancePublicId,
                                       const std::set<DicomTag>& ignoreTagLength)
   {
+    // TODO-FIND: This is a compatibility method, should be removed
+
+    std::map<MetadataType, std::string> metadata;
+    std::map<FileContentType, FileInfo> attachments;
+
+    FileInfo attachment;
+    int64_t revision;  // Ignored
+
+    if (index_.LookupAttachment(attachment, revision, instancePublicId, FileContentType_Dicom))
+    {
+      attachments[FileContentType_Dicom] = attachment;
+    }
+
+    if (index_.LookupAttachment(attachment, revision, instancePublicId, FileContentType_DicomUntilPixelData))
+    {
+      attachments[FileContentType_DicomUntilPixelData] = attachment;
+    }
+
+    if (index_.LookupAttachment(attachment, revision, instancePublicId, FileContentType_DicomAsJson))
+    {
+      attachments[FileContentType_DicomAsJson] = attachment;
+    }
+
+    std::string s;
+    if (index_.LookupMetadata(s, revision, instancePublicId, ResourceType_Instance,
+                              MetadataType_Instance_PixelDataOffset))
+    {
+      metadata[MetadataType_Instance_PixelDataOffset] = s;
+    }
+
+    ReadDicomAsJson(result, instancePublicId, metadata, attachments, ignoreTagLength);
+  }
+
+
+  void ServerContext::ReadDicomAsJson(Json::Value& result,
+                                      const std::string& instancePublicId,
+                                      const std::map<MetadataType, std::string>& instanceMetadata,
+                                      const std::map<FileContentType, FileInfo>& instanceAttachments,
+                                      const std::set<DicomTag>& ignoreTagLength)
+  {
     /**
      * CASE 1: The DICOM file, truncated at pixel data, is available
      * as an attachment (it was created either because the storage
@@ -1043,9 +1132,8 @@
      **/
     
     FileInfo attachment;
-    int64_t revision;  // Ignored
 
-    if (index_.LookupAttachment(attachment, revision, instancePublicId, FileContentType_DicomUntilPixelData))
+    if (LookupAttachment(attachment, FileContentType_DicomUntilPixelData, instanceAttachments))
     {
       std::string dicom;
 
@@ -1071,8 +1159,7 @@
 
       {
         std::string s;
-        if (index_.LookupMetadata(s, revision, instancePublicId, ResourceType_Instance,
-                                  MetadataType_Instance_PixelDataOffset))
+        if (LookupMetadata(s, MetadataType_Instance_PixelDataOffset, instanceMetadata))
         {
           hasPixelDataOffset = false;
 
@@ -1103,7 +1190,7 @@
 
       if (hasPixelDataOffset &&
           area_.HasReadRange() &&
-          index_.LookupAttachment(attachment, revision, instancePublicId, FileContentType_Dicom) &&
+          LookupAttachment(attachment, FileContentType_Dicom, instanceAttachments) &&
           attachment.GetCompressionType() == CompressionType_None)
       {
         /**
@@ -1126,7 +1213,7 @@
         InjectEmptyPixelData(result);
       }
       else if (ignoreTagLength.empty() &&
-               index_.LookupAttachment(attachment, revision, instancePublicId, FileContentType_DicomAsJson))
+               LookupAttachment(attachment, FileContentType_DicomAsJson, instanceAttachments))
       {
         /**
          * CASE 3: This instance was created using Orthanc <=
@@ -1755,6 +1842,7 @@
       }
     }
 
+#if ORTHANC_ENABLE_PLUGINS == 1
     if (HasPlugins() && GetPlugins().HasCustomTranscoder())
     {
       LOG(INFO) << "The plugins and built-in image decoders failed to decode a frame, "
@@ -1772,6 +1860,7 @@
         return file->DecodeFrame(frameIndex);
       }
     }
+#endif
 
     return NULL;
   }