Add possibility for head only object

In case the file name is set to 'headersOnly' an empty object with only
headers is created. This is e.g. necessary for pure redirect entries.

Author: wiechula

CCDB/src/UploadTool.cxx

@@ -147,33 +147,41 @@ int main(int argc, char* argv[])
     meta[p.first] = p.second;
   }
 
-  TFile f(filename.c_str());
-  auto key = f.GetKey(keyname.c_str());
-  if (key) {
-    // get type of key
-    auto classname = key->GetClassName();
-    auto tcl = TClass::GetClass(classname);
-    auto object = f.Get<void>(keyname.c_str());
-    if (tcl->InheritsFrom("TTree")) {
-      auto tree = static_cast<TTree*>(object);
-      tree->LoadBaskets(0x1L << 32); // make tree memory based
-      tree->SetDirectory(nullptr);
-    }
-    // convert classname to typeinfo
-    // typeinfo
-    auto ti = tcl->GetTypeInfo();
-
-    std::cout << " Uploading an object of type " << key->GetClassName()
-              << " to path " << path << " with timestamp validity from " << starttimestamp
-              << " to " << endtimestamp << "\n";
-
-    api.storeAsTFile_impl(object, *ti, path, meta, starttimestamp, endtimestamp);
+  if (filename == "headersOnly") {
+    api.storeAsBinaryFile(nullptr, 0, "ignored", "", path, meta, starttimestamp, endtimestamp);
     if (!api.isSnapshotMode() && meta.find("adjustableEOV") != meta.end() && meta.find("default") == meta.end()) {
-      o2::ccdb::CcdbObjectInfo oi(path, classname, filename, meta, starttimestamp, endtimestamp);
+      o2::ccdb::CcdbObjectInfo oi(path, "", "", meta, starttimestamp, endtimestamp);
       o2::ccdb::adjustOverriddenEOV(api, oi);
     }
   } else {
-    std::cerr << "Key " << keyname << " does not exist\n";
+    TFile f(filename.c_str());
+    auto key = f.GetKey(keyname.c_str());
+    if (key) {
+      // get type of key
+      auto classname = key->GetClassName();
+      auto tcl = TClass::GetClass(classname);
+      auto object = f.Get<void>(keyname.c_str());
+      if (tcl->InheritsFrom("TTree")) {
+        auto tree = static_cast<TTree*>(object);
+        tree->LoadBaskets(0x1L << 32); // make tree memory based
+        tree->SetDirectory(nullptr);
+      }
+      // convert classname to typeinfo
+      // typeinfo
+      auto ti = tcl->GetTypeInfo();
+
+      std::cout << " Uploading an object of type " << key->GetClassName()
+                << " to path " << path << " with timestamp validity from " << starttimestamp
+                << " to " << endtimestamp << "\n";
+
+      api.storeAsTFile_impl(object, *ti, path, meta, starttimestamp, endtimestamp);
+      if (!api.isSnapshotMode() && meta.find("adjustableEOV") != meta.end() && meta.find("default") == meta.end()) {
+        o2::ccdb::CcdbObjectInfo oi(path, classname, filename, meta, starttimestamp, endtimestamp);
+        o2::ccdb::adjustOverriddenEOV(api, oi);
+      }
+    } else {
+      std::cerr << "Key " << keyname << " does not exist\n";
+    }
   }
 
   return 0;