Dedicated backend class

gicmo commented 7 years ago

Currently we don't have a dedicated class representing a backend (filesystem, hdf5, etcpp). It might be nice to have such a thing for various reason:

Query backend specific information (default file ending, name, version, support for feature xyz)
Tweak backend specific defaults (compression level, chunk size)
specialized open method: Currently the only way to open a file is via File::open(). If you now want to open a file with backend specific flags (compression mode and level) we could either add all these options (as generic property key-value pairs?) or we could have a specialized open method with all the backend specific options, i.e. H5Backend::open("file.hd5", <Chunksize>, <Compression>).

gicmo commented 7 years ago

Could also be used to query backend file format version, and have checks to see if a given file can be opened in what mode (read, write) or not at all. Maybe could also be used to convert files to newer versions.

achilleas-k commented 7 years ago

I wonder if it would be useful to convert files between backends. For instance open an HDF5 file and save everything to the filesystem.

jgrewe commented 7 years ago

yes, definitely, cf #518

G-Node / nix

Dedicated backend class #671