Capabilities and Known Issues

HDF Product Designer aims to make the design process of HDF5 file content easier and intuitive. However, using this software still requires knowledge of the HDF5 data model and familiarity with the main features of its programming interface. Consider the following when deciding whether to use this software:

  • NASA’s Earthdata Login is currently the only user authentication available.

  • Data interoperability in the Earth Science domain is supported only.

  • No HDF5 files are being created/edited during the design process. HDF Product Designer implements an alternative backend storage (see System Design) that allows unlimited editing of HDF5 content.

  • HDF5 features not supported:

    • HDF5 object and region reference datatypes
    • Composite datatypes, with only a few exceptions
    • Fixed-length Unicode strings
    • Multiple HDF5 path names

Known Issues

HDF Product Designer is being actively maintained. Listed below are currently known issues:

  • Importing a design will continue despite any reported errors. It is currently not possible to abort that process.
  • Importing designs from HDF5 files containing HDF5 objects with multiple path names will create those objects for one of their path names and produce create object errors for all the subsequent path names. Multiple path names for one HDF5 object exist when that object is the target of more than one HDF5 link. It isn’t possible to add the missing HDF5 links after the design import.
  • Unattached dimensions (not associated with at least one dataset in the design) are not recognized as such when the design is opened again. To prevent this, attach every dimension to at least one dataset prior to closing the design.
  • The netCDF system attributes, those attached to netCDF variables with names prefixed with the underscore (“_”), are imported although they do not have any special meaning in HDF5. This is especially relevant for the _FillValue and _ChunkSizes attributes. Editing values of these two attributes will not affect that HDF5 dataset’s fill value or chunk size.
  • string datatype dataset in design will appear as vlstring datatype when the design is saved and re-opened.
  • CF validation using the NCO’s ncdismember tool may not work for the HTTP access. In case the browser window displays a failure to open the page please replace http with https in the URL field and try again. Contact us if even the HTTPS URL fails.
  • Nested compound datatype is not supported.
  • Exporting designs with an array datatype compound field is not yet supported by all source code generators.
  • vlstring (variable-length string) datatype cannot be used as a compound datatype member.
  • Choosing both CF and NUG for conventions when creating a new design is not supported. Select either one only.
  • Convention support works for new designs only. Changing design’s convention later is not supported.
  • Support for the HDF-EOS convention is still in very early stages of development. It will not yield valid HDF-EOS5 template files because it is not possible to assign values to datasets. Specifically, it is not possible to store an ODL string into the StructMetadata dataset which is essential for HDF-EOS5 library to access the file.
  • Export as works only for the current working version (label:HEAD).
  • Design/dataset/attribute/group names cannot be longer than 255 characters.
  • The / character is not allowed in object names and will be replaced with the _ character.
  • The size of attribute’s value cannot exceed one gigabyte.
  • There is a 30-second timeout limit for all operations. Long executing operations, like template file generation or validation, may fail due to this timeout.
  • Generating HDF5 template files for designs with large attributes (storage size greater than 64 kilobytes) may fail with an error: Unable to create attribute (object header message is too large).
  • Linux binary may not work if your Linux system is behind firewalls and proxies because authentication with Earthdata Login will fail.

To report any new issue please visit the issue tracking website. (NASA Earthdata login required.)