Generate an additional cmake lists file containing the generated sour…

…ce files (#143)

* Create cmake lists file with generated files

* Make templates and yaml file changes retrigger cmake

* Make changes to the code generator retrigger generation

* Make macro abort cmake if datamodel cannot be generated

.gitignore

@@ -55,3 +55,6 @@ spack*
 # Tooling
 /.clangd/
 /compile_commands.json
+
+# Generated files
+*podio_generated_files.cmake

cmake/podioMacros.cmake

@@ -134,27 +134,37 @@ function(PODIO_GENERATE_DATAMODEL datamodel YAML_FILE RETURN_HEADERS RETURN_SOUR
     # At least build the ROOT selection.xml by default for now
     SET(ARG_IO_BACKEND_HANDLERS "ROOT")
   ENDIF()
+
+  # Make sure that we re run the generation process everytime either the
+  # templates or the yaml file changes.
+  include(${podio_PYTHON_DIR}/templates/CMakeLists.txt)
+  set_property(
+    DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS
+    ${YAML_FILE}
+    ${PODIO_TEMPLATES}
+    ${podio_PYTHON_DIR}/podio_class_generator.py
+    ${podio_PYTHON_DIR}/generator_utils.py
+    ${podio_PYTHON_DIR}/podio_config_reader.py
+  )
+
+  message(STATUS "Creating '${datamodel}' datamodel")
   # we need to boostrap the data model, so this has to be executed in the cmake run
   execute_process(
-    COMMAND ${CMAKE_COMMAND} -E echo "Creating \"${datamodel}\" data model"
     COMMAND python ${podio_PYTHON_DIR}/podio_class_generator.py ${YAML_FILE} ${ARG_OUTPUT_FOLDER} ${datamodel} ${ARG_IO_BACKEND_HANDLERS}
     WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+    RESULT_VARIABLE podio_generate_command_retval
     )
 
-  file(GLOB headers ${ARG_OUTPUT_FOLDER}/${datamodel}/*.h)
-  file(GLOB sources ${ARG_OUTPUT_FOLDER}/src/*.cc)
+  IF(NOT ${podio_generate_command_retval} EQUAL 0)
+    message(FATAL_ERROR "Could not generate datamodel '${datamodel}'. Check your definition in '${YAML_FILE}'")
+  ENDIF()
+
+  # Get the generated headers and source files
+  include(${ARG_OUTPUT_FOLDER}/podio_generated_files.cmake)
 
   set (${RETURN_HEADERS} ${headers} PARENT_SCOPE)
   set (${RETURN_SOURCES} ${sources} PARENT_SCOPE)
 
-  add_custom_target(create_${datamodel}
-    COMMENT "Re-Creating \"${datamodel}\" data model"
-    DEPENDS ${YAML_FILE}
-    BYPRODUCTS ${sources} ${headers}
-    COMMAND python ${podio_PYTHON_DIR}/podio_class_generator.py --quiet ${YAML_FILE} ${ARG_OUTPUT_FOLDER} ${datamodel} ${ARG_IO_BACKEND_HANDLERS}
-    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-    )
-
 endfunction()
 
 

python/podio_class_generator.py

@@ -3,7 +3,6 @@
 from __future__ import unicode_literals, absolute_import, print_function
 
 import os
-import errno
 import sys
 import subprocess
 from io import open
@@ -56,6 +55,24 @@ def get_clang_format():
     return []
 
 
+def write_file_if_changed(filename, content, force_write=False):
+  """Write the file contents only if it has changed or if the file does not exist
+  yet. Return whether the file has been written or not"""
+  try:
+    with open(filename, 'r') as f:
+      existing_content = f.read()
+      changed = existing_content != content
+  except FileNotFoundError:
+    changed = True
+
+  if changed or force_write:
+    with open(filename, 'w') as f:
+      f.write(content)
+    return True
+
+  return False
+
+
 class ClassGenerator(object):
   def __init__(self, yamlfile, install_dir, package_name, io_handlers, verbose, dryrun):
     self.install_dir = install_dir
@@ -84,6 +101,8 @@ def __init__(self, yamlfile, install_dir, package_name, io_handlers, verbose, dr
     self.expose_pod_members = self.reader.options["exposePODMembers"]
 
     self.clang_format = []
+    self.generated_files = []
+    self.any_changes = False
 
   def process(self):
     for name, component in self.reader.components.items():
@@ -96,6 +115,8 @@ def process(self):
       self._create_selection_xml()
     self.print_report()
 
+    self._write_cmake_lists_file()
+
   def print_report(self):
     if not self.verbose:
       return
@@ -126,26 +147,13 @@ def _write_file(self, name, content):
     else:
       fullname = os.path.join(self.install_dir, "src", name)
     if not self.dryrun:
+      self.generated_files.append(fullname)
       if self.clang_format:
         cfproc = subprocess.Popen(self.clang_format, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
         content = cfproc.communicate(input=content.encode())[0].decode()
 
-      try:
-        with open(fullname, 'r') as f:
-          existing_content = f.read()
-          changed = existing_content != content
-
-      except EnvironmentError as e:
-        # If we deprecate python2 support, FileNotFoundError becomes available
-        # and this can be using it. For now we keep it compatible with both
-        # versions
-        if e.errno != errno.ENOENT:
-          raise
-        changed = True
-
-      if changed:
-        with open(fullname, 'w') as f:
-          f.write(content)
+      changed = write_file_if_changed(fullname, content)
+      self.any_changes = changed or self.any_changes
 
   @staticmethod
   def _get_filenames_templates(template_base, name):
@@ -377,6 +385,42 @@ def _get_member_includes(self, members):
 
     return self._sort_includes(includes)
 
+  def _write_cmake_lists_file(self):
+    """Write the names of all generated header and src files into cmake lists"""
+    header_files = (f for f in self.generated_files if f.endswith('.h'))
+    src_files = (f for f in self.generated_files if f.endswith('.cc'))
+    xml_files = (f for f in self.generated_files if f.endswith('.xml'))
+
+    def _write_list(name, target_folder, files, comment):
+      """Write all files into a cmake variable using the target_folder as path to the
+      file"""
+      list_cont = []
+
+      list_cont.append(f'# {comment}')
+      list_cont.append(f'SET({name}')
+      for full_file in files:
+        fname = os.path.basename(full_file)
+        list_cont.append(f'  {os.path.join(target_folder, fname)}')
+
+      list_cont.append(')')
+      list_cont.append(f'SET_PROPERTY(SOURCE ${{{name}}} PROPERTY GENERATED TRUE)\n')
+
+      return '\n'.join(list_cont)
+
+    full_contents = ['#-- AUTOMATICALLY GENERATED FILE - DO NOT EDIT -- \n']
+    full_contents.append(_write_list('headers', r'${ARG_OUTPUT_FOLDER}/${datamodel}',
+                                     header_files, 'Generated header files'))
+
+    full_contents.append(_write_list('sources', r'${ARG_OUTPUT_FOLDER}/src',
+                                     src_files, 'Generated source files'))
+
+    full_contents.append(_write_list('selection_xml', r'${ARG_OUTPUT_FOLDER}/src',
+                                     xml_files, 'Generated xml files'))
+
+    write_file_if_changed(f'{self.install_dir}/podio_generated_files.cmake',
+                          '\n'.join(full_contents),
+                          self.any_changes)
+
   @staticmethod
   def _is_pod_type(members):
     """Check if the members of the class define a POD type"""

python/templates/CMakeLists.txt

@@ -0,0 +1,23 @@
+set(PODIO_TEMPLATES
+  ${CMAKE_CURRENT_LIST_DIR}/Collection.cc.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/Collection.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/CollectionData.cc.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/CollectionData.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/Component.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/ConstObject.cc.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/ConstObject.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/Data.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/Obj.cc.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/Object.cc.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/Object.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/Obj.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/selection.xml.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/SIOBlock.cc.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/SIOBlock.h.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/macros/collections.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/macros/declarations.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/macros/implementations.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/macros/iterator.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/macros/sioblocks.jinja2
+  ${CMAKE_CURRENT_LIST_DIR}/macros/utils.jinja2
+)