adds processing provenance to an HDU table

punchbowl/data/io.py

@@ -88,11 +88,14 @@ def write_ndcube_to_fits(cube: NDCube,
                                             header=full_header,
                                             name="Uncertainty array",
                                             quantize_level=uncertainty_quantize_level)
+        hdu_provenance = fits.BInTableHDU.from_columns(fits.ColDefs([fits.Column(
+            name="provenance", format="A40", array=np.char.array(cube.meta.provenance))]))
 
         hdul = cube.wcs.to_fits()
         hdul[0] = fits.PrimaryHDU()
         hdul.insert(1, hdu_data)
         hdul.insert(2, hdu_uncertainty)
+        hdul.insert(3, hdu_provenance)
         hdul.writeto(filename, overwrite=overwrite, checksum=True)
         hdul.close()
         if write_hash:
@@ -162,6 +165,7 @@ def load_ndcube_from_fits(path: str | Path, key: str = " ") -> NDCube:
         header["CHECKSUM"] = ""
         header["DATASUM"] = ""
         meta = NormalizedMetadata.from_fits_header(header)
+        meta.provenance = hdul[-1].data["provenance"]
         wcs = WCS(header, hdul, key=key)
         unit = u.ct
 

punchbowl/data/meta.py

@@ -208,6 +208,7 @@ def __init__(
             self,
             contents: t.OrderedDict[str, t.OrderedDict[str, MetaField]],
             history: History | None = None,
+            provenance: list[str] | None = None,
             wcs_section_name: str = "World Coordinate System",
     ) -> None:
         """
@@ -219,12 +220,15 @@ def __init__(
             contents of the meta information
         history: History
             history contents for this meta field
+        provenance: list[str]
+            list of files used in the generation of this product
         wcs_section_name: str
             the section title for the WCS section to specially fill
 
         """
         self._contents = contents
         self._history = history if history is not None else History()
+        self._provenance = provenance if history is not None else []
         self._wcs_section_name = wcs_section_name
 
     def __iter__(self) -> t.Iterator[t.Any]:
@@ -616,6 +620,11 @@ def history(self) -> History:
     def history(self, history: History) -> None:
         self._history = history
 
+    @property
+    def provenance(self) -> list[str]:
+        """Returns file provenance."""
+        return self._provenance
+
     @staticmethod
     def _validate_key_is_str(key: str) -> None:
         """