Allow empty value match for fields #3015
Open
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Motivation
In the current version of
EnvFilter
, the directive[span{field=}]
does not work as expected.The directive
[span{field}]
filter for all spansspan
that have a fieldfield
while the directive[{field=a}]
filters for all spansspan
where the fieldfield
has the valuea
. In contrast, the directive[span{field=}]
filters only for spansspan
. IMHO this is unexpected behavior.Solution
Digging into the code for parsing
Directive
s the regex for field matches didn't consider thefield=
case. This PR changes the regex so thatfield=
is interpreted as a match on an empty string.With regex enabled this means that now
field=
behaves likefield
.Alternative solution
Instead of accepting the
field=
directive, it could trigger an error instead invalidating the whole directive.