Fix up edl_cmd_shell for os commands #44
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When invoked as "sdo_write c3 os_command command ..." this patch fixes two thing: - ... can now have spaces in it - command is defined as DOMAIN which we didn't handle. There's some amount of stuff built around the assumption that we don't use DOMIAIN at all but this is what we shipped so we've got to support it now. Amusingly it looks like pycanopen's `encode_raw()` has a bug where it doesn't convert strings to bytes correctly so it's done manually here.
cfdp-py has updated with handy bug fixes! Unfortunately those conflict with our fixes so until we can properly ship a new version to space let's fix the version to what we've been developing with.
Similar to cmd_shell and ping, this makes it easy to coordinate with those other scripts.
scripts/edl_cmd_shell.py
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| @@ -284,8 +284,10 @@ def do_sdo_write(self, arg: str): | |||
| value = float(args[3]) | |||
| elif obj.data_type == canopen.objectdictionary.VISIBLE_STRING: | |||
| value = args[3] | |||
| elif obj.data_type == canopen.objectdictionary.DOMAIN: | |||
| value = args[3].encode("ascii") | |||
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This assume the value is string, domain type are void, so this wont work in all cases. It would be more robust to expect the user to past a hex string for domain types.
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I guess the quick encode a string will work for now
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This is a good point, I would prefer to do it properly over quick hacks. Looking through CiA-301 and oresat-configs it feels like while officially undefined the intended use for DOMAIN is for file transfers; if the data is short enough to be written as a hex string easily it should generally be OCTET_STRING. What if instead for DOMAIN we expect a filename and do_sdo_write() opens and sends the contents?
On the other hand it looks like the type is wrong for OS command in oresat-configs. The command should be OCTET_STRING instead of DOMAIN (CiA-301 7.4.8.6). Additionally 7.5.2.26 says command should be "ISO8859 [ASCII] characters or binary". So given that, what if in do_sdo_write() for OCTET_STRING we try to decode the argument from a hex string to bytes and if that fails then just .encode("ascii") the given string? That way we cans still send shell commands directly through sdo_write.
In code:
...
elif obj.data_type == canopen.objectdictionary.DOMAIN:
with open(arg[3], 'rb') as f:
value = f.read()
elif obj.data_type == canopen.objectdictionary.OCTET_STRING:
try:
value = bytes.fromhex(arg[3])
except ValueError:
value = arg[3].encode("ascii")There was a problem hiding this comment.
Yea, that sounds like a good plan
In 5f961ed I added DOMAIN handling so that we could send os commands, but DOMAIN really is supposed to be for file-like things. This enhances sdo_write to interpret the final argument instead as a filename, which it then opens and sends. Additionally os commands really should have been of type OCTET_STRING but that needs to be fixed in oresat-configs. This adds OCTET_STRING handling in anticipation of that.
When invoked as "sdo_write c3 os_command command ..." this patch fixes two thing:
encode_raw()has a bug where it doesn't convert strings to bytes correctly so it's done manually here.