tdate is not defined

[dgpetrie]

RFC 8610 defines the CDDL standard prelude in appendix D. This defines tdate.
zcbor yields an exception: KeyError: 'tdate' when is is reference in CDDL.

import zcbor
cddl_str = """
date_type = {
creation: tdate
}
"""
cddl_res = zcbor.zcbor.zcbor.DataTranslator.from_cddl(cddl_str, 100)
Traceback (most recent call last):
File "", line 1, in
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 293, in from_cddl
my_types[my_type].post_validate()
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 937, in post_validate
none_keys = [child for child in self.value if not child.elem_has_key()]
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 937, in
none_keys = [child for child in self.value if not child.elem_has_key()]
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 928, in elem_has_key
or (self.type == "OTHER" and self.my_types[self.value].elem_has_key())
KeyError: 'tdate'

If I add the RFC8610 prelude definition of tdate the following exception is raise:

import zcbor
cddl_str = """
date_type = {
creation: tdate
}

tdate = #6.0(tstr)
"""
cddl_res = zcbor.zcbor.zcbor.DataTranslator.from_cddl(cddl_str, 100)
Traceback (most recent call last):
File "", line 1, in
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 293, in from_cddl
my_types[my_type].post_validate()
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 940, in post_validate
raise TypeError(
TypeError: Map member(s) must have key: [creation:OTHER'tdate'] pointing to [#6.0TSTR]

I have not tested other types defined in the RFC 8610 standard prelude. Perhaps none are defined?

[dgpetrie]

The following approach for tdate does not work either:

cddl_str = """
date_type = {
creation: #6.0(tstr)
}
"""

cddl_res = zcbor.zcbor.zcbor.DataTranslator.from_cddl(cddl_str, 100)
Traceback (most recent call last):
File "", line 1, in
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 293, in from_cddl
my_types[my_type].post_validate()
File "/usr/local/lib/python3.8/dist-packages/zcbor/zcbor/zcbor.py", line 940, in post_validate
raise TypeError(
TypeError: Map member(s) must have key: [creation:#6.0TSTR] pointing to []

[dgpetrie]

Testing was performed in Python 3.8 using zcbor version 0.8.1

[oyvindronningstad]

Thanks.

The prelude is added by default when using the CLI, but not when using the Python module. The prelude can be found in the repo at zcbor/prelude.cddl, you can programmatically append it to the cddl_str. I will look into making it easier to add the when using the python module.

Your second comment seems to fail because you are defining a map, but the member has no well-formed key. Try e.g.

cddl_str = """
date_type = {
    "creation" => #6.0(tstr)
}
"""