check if key exists

[electriquo]

Although I browsed search and search optional documentation, I did not find how to check whether a key exists (a functionality which is equivalent to jq has()).

The motivation:

1. Check whether the input has specific key. E.g. does {} has .foo.bar?
2. Read (select) a key only if it exists

[TomWright]

The - character when used in a dynamic/search selector can be used to check the key/property name in an array/object, however it doesn't work in this case.

Dasel returns an exit code of 1 if it failed to find the item though so I wonder if you could just run a basic selector and check the exit code?

~ [] $ echo '{"name":"Tom"}' | dasel -r json .name
"Tom"
~ [] $ echo $?
0
~ [] $ echo '{"name":"Tom"}' | dasel -r json .age
Error: could not query node: could not find value: no value found for selector: .age: map[name:Tom]
~ [] $ echo $?
1

[electriquo]

That is what I did and yet was wondering whether there is any better way.
Thanks.

[TomWright]

If there's a lot of interest I could add a command but seeing as it's already possible it's not a high priority