Extend CCDB functions with optional headers

Author: mrtineide

CCDB/include/CCDB/BasicCCDBManager.h

@@ -98,9 +98,9 @@ class CCDBManagerInstance
   /// query timestamp
   long getTimestamp() const { return mTimestamp; }
 
-  /// retrieve an object of type T from CCDB as stored under path and timestamp
+  /// retrieve an object of type T from CCDB as stored under path and timestamp. Optional to get the headers
   template <typename T>
-  T* getForTimeStamp(std::string const& path, long timestamp);
+  T* getForTimeStamp(std::string const& path, long timestamp, std::map<std::string, std::string>* headers = nullptr);
 
   /// retrieve an object of type T from CCDB as stored under path and using the timestamp in the middle of the run
   template <typename T>
@@ -235,7 +235,7 @@ class CCDBManagerInstance
 };
 
 template <typename T>
-T* CCDBManagerInstance::getForTimeStamp(std::string const& path, long timestamp)
+T* CCDBManagerInstance::getForTimeStamp(std::string const& path, long timestamp, std::map<std::string, std::string>* headers)
 {
   mHeaders.clear(); // we clear at the beginning; to allow to retrieve the header information in a subsequent call
   T* ptr = nullptr;
@@ -262,6 +262,9 @@ T* CCDBManagerInstance::getForTimeStamp(std::string const& path, long timestamp)
     auto& cached = mCache[path];
     cached.queries++;
     if ((!isOnline() && cached.isCacheValid(timestamp)) || (mCheckObjValidityEnabled && cached.isValid(timestamp))) {
+      if (headers) {
+        *headers = mHeaders;
+      }
       return reinterpret_cast<T*>(cached.noCleanupPtr ? cached.noCleanupPtr : cached.objPtr.get());
     }
     ptr = mCCDBAccessor.retrieveFromTFileAny<T>(path, mMetaData, timestamp, &mHeaders, cached.uuid,
@@ -321,6 +324,9 @@ T* CCDBManagerInstance::getForTimeStamp(std::string const& path, long timestamp)
       mFailures++;
     }
   }
+  if (headers) {
+    *headers = mHeaders; // Do a deep copy of the headers
+  }
   auto end = std::chrono::system_clock::now();
   mTimerMS += std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
   return ptr;

CCDB/include/CCDB/CcdbApi.h

@@ -281,7 +281,7 @@ class CcdbApi //: public DatabaseInterface
    *  @return: True in case operation successful or false if there was a failure/problem.
    */
   bool retrieveBlob(std::string const& path, std::string const& targetdir, std::map<std::string, std::string> const& metadata, long timestamp,
-                    bool preservePathStructure = true, std::string const& localFileName = "snapshot.root", std::string const& createdNotAfter = "", std::string const& createdNotBefore = "") const;
+                    bool preservePathStructure = true, std::string const& localFileName = "snapshot.root", std::string const& createdNotAfter = "", std::string const& createdNotBefore = "", std::map<std::string, std::string>* headers = nullptr) const;
 
   /**
    * Retrieve the headers of a CCDB entry, if it exists.

CCDB/src/CcdbApi.cxx

@@ -831,7 +831,7 @@ TObject* CcdbApi::retrieveFromTFile(std::string const& path, std::map<std::strin
 }
 
 bool CcdbApi::retrieveBlob(std::string const& path, std::string const& targetdir, std::map<std::string, std::string> const& metadata,
-                           long timestamp, bool preservePath, std::string const& localFileName, std::string const& createdNotAfter, std::string const& createdNotBefore) const
+                           long timestamp, bool preservePath, std::string const& localFileName, std::string const& createdNotAfter, std::string const& createdNotBefore, std::map<std::string, std::string>* outHeaders) const
 {
 
   // we setup the target path for this blob
@@ -879,6 +879,9 @@ bool CcdbApi::retrieveBlob(std::string const& path, std::string const& targetdir
   CCDBQuery querysummary(path, metadata, timestamp);
 
   updateMetaInformationInLocalFile(targetpath.c_str(), &headers, &querysummary);
+  if (outHeaders) {
+    *outHeaders = std::move(headers); // Re-use the same headers to give back to the callee
+  }
   return true;
 }