Attempt to extract WCS from JWST spectrum

read_asdf_2.log

In [1]: import astropy

In [2]: astropy.__version__
Out[2]: '3.1.dev21573'

In [3]: import asdf

In [4]: asdf.__version__
Out[4]: '2.0.0.dev1248'

In [5]: import gwcs

In [6]: gwcs.__version__
Out[6]: '0.8.0'

In [7]: from astropy.io import fits

In [8]: hdulist = fits.open('/grp/jwst/ssb/test_build7.1/examples_for_dms/level2
   ...: /mir_lrs_fixedslit/jw00035001001_01101_00001_mirimage_x1d.fits')

In [9]: hdulist.info()
Filename: /grp/jwst/ssb/test_build7.1/examples_for_dms/level2/mir_lrs_fixedslit/jw00035001001_01101_00001_mirimage_x1d.fits
No.    Name      Ver    Type      Cards   Dimensions   Format
  0  PRIMARY       1 PrimaryHDU     351   ()      
  1  EXTRACT1D     1 BinTableHDU     26   387R x 8C   [D, D, D, J, D, D, D, D]   
  2  ASDF          1 ImageHDU         7   (29547,)   uint8   

In [10]: fa = asdf.fits_embed.AsdfInFits.open(hdulist)

In [11]: w = fa.tree['meta']['wcsinfo']  # fa['wcs'] does not work

In [12]: type(w)
Out[12]: dict

In [13]: w
Out[13]: 
{'cdelt1': 0.11,
 'cdelt2': 0.11,
 'crpix1': 516.0,
 'crpix2': 512.0,
 'crval1': 5.63056810618,
 'crval2': -72.0545718428,
 'crval3': 0.0,
 'ctype1': 'RA---TAN',
 'ctype2': 'DEC--TAN',
 'ctype3': 'WAVE',
 'cunit1': 'deg',
 'cunit2': 'deg',
 'cunit3': 'micron',
 'dec_ref': -72.0545718428,
 'pc1_1': 1.0,
 'pc1_2': 0.0,
 'pc2_1': 0.0,
 'pc2_2': 1.0,
 'pc3_1': 0.0,
 'pc3_2': 1.0,
 'ra_ref': 5.63056810618,
 'roll_ref': 3.812,
 's_region': '0.0',
 'v2_ref': -415.0568,
 'v3_ref': -400.2337,
 'v3yangle': 5.0152,
 'wcsaxes': 3}

In [14]: gwcs.WCS(w)
...
TypeError: Expected forward_transform to be a model or a (frame, transform) list, got <class 'dict'>