Move NexusDescriptor to Framework/Nexus

This is in preparation for using it inside of Nexus::File

Author: peterfpeterson

Framework/Nexus/inc/MantidNexus/NexusDescriptor.h

@@ -90,6 +90,8 @@ class MANTID_NEXUS_DLL NexusDescriptor {
   /// Query if a given type exists somewhere in the file
   bool classTypeExists(const std::string &classType) const;
 
+  void addEntry(const std::string &entryName, const std::string &groupClass);
+
 private:
   /**
    * Sets m_allEntries, called in HDF5 constructor.
@@ -98,9 +100,9 @@ class MANTID_NEXUS_DLL NexusDescriptor {
   std::map<std::string, std::set<std::string>> initAllEntries();
 
   /** NeXus HDF5 file name */
-  std::string m_filename;
+  const std::string m_filename;
   /// Extension
-  std::string m_extension;
+  const std::string m_extension;
   /// First entry name/type
   std::pair<std::string, std::string> m_firstEntryNameType;
   /// Root attributes
@@ -114,7 +116,7 @@ class MANTID_NEXUS_DLL NexusDescriptor {
    *          (e.g. /entry/log)
    * </pre>
    */
-  const std::map<std::string, std::set<std::string>> m_allEntries;
+  std::map<std::string, std::set<std::string>> m_allEntries;
 };
 
 } // namespace Nexus

Framework/Nexus/src/NexusDescriptor.cpp

@@ -68,7 +68,8 @@ void getGroup(H5::Group groupID, std::map<std::string, std::set<std::string>> &a
 } // namespace
 
 NexusDescriptor::NexusDescriptor(std::string filename)
-    : m_filename(std::move(filename)), m_extension(), m_firstEntryNameType(), m_allEntries(initAllEntries()) {}
+    : m_filename(std::move(filename)), m_extension(std::filesystem::path(m_filename).extension().string()),
+      m_firstEntryNameType(), m_allEntries(initAllEntries()) {}
 
 // PUBLIC
 const std::string &NexusDescriptor::filename() const noexcept { return m_filename; }
@@ -78,10 +79,31 @@ bool NexusDescriptor::hasRootAttr(const std::string &name) const { return (m_roo
 const std::map<std::string, std::set<std::string>> &NexusDescriptor::getAllEntries() const noexcept {
   return m_allEntries;
 }
+void NexusDescriptor::addEntry(const std::string &entryName, const std::string &groupClass) {
+  // simple checks
+  if (entryName.empty())
+    throw std::runtime_error("Cannot add empty path");
+  if (groupClass.empty())
+    throw std::runtime_error("Cannot add empty class");
+  if (entryName.find("/") != 0)
+    throw std::runtime_error("Paths must be absolute: " + entryName);
+
+  // do not add path twice
+  if (this->isEntry(entryName))
+    throw std::runtime_error("Cannot add an entry twice: " + entryName);
+
+  // verify the parent exists
+  const auto lastPos = entryName.rfind("/");
+  const auto parentPath = entryName.substr(0, lastPos);
+  if (!this->isEntry(parentPath))
+    throw std::runtime_error("Parent path " + parentPath + " does not exist");
+
+  // add the path
+  m_allEntries[groupClass].insert(entryName);
+}
 
 // PRIVATE
 std::map<std::string, std::set<std::string>> NexusDescriptor::initAllEntries() {
-  m_extension = std::filesystem::path(m_filename).extension().string();
   H5::FileAccPropList access_plist;
   access_plist.setFcloseDegree(H5F_CLOSE_STRONG);
 

Framework/Nexus/test/NexusDescriptorTest.h

@@ -93,4 +93,28 @@ class NexusDescriptorTest : public CxxTest::TestSuite {
     TS_ASSERT(nexusHDF5Descriptor.hasRootAttr("file_name"));
     TS_ASSERT(!nexusHDF5Descriptor.hasRootAttr("not_attr"));
   }
+
+  void test_AddEntry() {
+    // create a descriptor with the correct values
+    const std::string filename = getFullPath("EQSANS_89157.nxs.h5");
+    Mantid::Nexus::NexusDescriptor nexusHDF5Descriptor(filename);
+
+    // verify that existing groups are there
+    TS_ASSERT_EQUALS(nexusHDF5Descriptor.isEntry("/entry/DASlogs", "NXcollection"), true);
+    TS_ASSERT_EQUALS(nexusHDF5Descriptor.isEntry("/entry/DASlogs/LambdaRequest", "NXlog"), true);
+    TS_ASSERT_EQUALS(nexusHDF5Descriptor.isEntry("/entry/DASlogs/OmikronRequest", "NXlog"), false);
+
+    // can't add a value with relative path
+    TS_ASSERT_THROWS(nexusHDF5Descriptor.addEntry("entry/DASlogs/OmikronRequest", "NXlog"), const std::runtime_error &);
+    TS_ASSERT_EQUALS(nexusHDF5Descriptor.isEntry("/entry/DASlogs/OmikronRequest", "NXlog"), false);
+
+    // make sure you can't add a group with invalid parent
+    TS_ASSERT_THROWS(nexusHDF5Descriptor.addEntry("/entry/DASlogginator/OmikronRequest", "NXlog"),
+                     const std::runtime_error &);
+    TS_ASSERT_EQUALS(nexusHDF5Descriptor.isEntry("/entry/DASlogginator/OmikronRequest", "NXlog"), false);
+
+    // add a field correctly
+    TS_ASSERT_THROWS_NOTHING(nexusHDF5Descriptor.addEntry("/entry/DASlogs/OmikronRequest", "NXlog"));
+    TS_ASSERT_EQUALS(nexusHDF5Descriptor.isEntry("/entry/DASlogs/OmikronRequest", "NXlog"), true);
+  }
 };