--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancServer/Resources/Samples/Lua/ClassifyUsingAet.lua	Tue Oct 13 15:36:48 2020 +0200
@@ -0,0 +1,49 @@
+-- Write the received DICOM instances to an external directory, and
+-- group the patients by the source AET that has sent the DICOM
+-- files. This sample is similar to "WriteToDisk.lua".
+
+
+TARGET = '/tmp/lua'
+
+
+function ToAscii(s)
+   -- http://www.lua.org/manual/5.1/manual.html#pdf-string.gsub
+   -- https://groups.google.com/d/msg/orthanc-users/qMLgkEmwwPI/6jRpCrlgBwAJ
+   return s:gsub('[^a-zA-Z0-9-/-: ]', '_')
+end
+
+
+function GetFromTable(t, key, defaultValue)
+   local result = t[key]
+   if result == nil or result == '' then
+      return defaultValue
+   else
+      return result
+   end
+end
+
+
+function OnStoredInstance(instanceId, tags, metadata, origin)
+   local dicom = RestApiGet('/instances/' .. instanceId .. '/file')
+   local tags = ParseJson(RestApiGet('/instances/' .. instanceId .. '/tags?simplify'))
+   local metadata = ParseJson(RestApiGet('/instances/' .. instanceId .. '/metadata?expand'))
+
+   local path = ToAscii(
+      TARGET .. '/' ..
+         GetFromTable(metadata, 'RemoteAET', 'None') .. '/'..
+         GetFromTable(tags, 'PatientID', '') .. ' - ' .. GetFromTable(tags, 'PatientName', '') .. '/' ..
+         GetFromTable(tags, 'StudyDate', '') .. ' - ' .. GetFromTable(tags, 'StudyDescription', '') .. '/' ..
+         GetFromTable(tags, 'SeriesDescription', ''))
+
+   -- Create the subdirectory (CAUTION: For Linux demo only, this is insecure!)
+   -- http://stackoverflow.com/a/16029744/881731
+   os.execute('mkdir -p "' .. path .. '"')
+   
+   -- Write to the file
+   local target = assert(io.open(path .. '/' .. GetFromTable(tags, 'SOPInstanceUID', 'none') .. '.dcm', 'wb'))
+   target:write(dicom)
+   target:close()
+
+   -- Optional step: Remove the source file
+   RestApiDelete('/instances/' .. instanceId)
+end