NodeGraph: Fix edges dataframe miscategorization

[lovasoa]

A dataframe named "edges" could end up getting categorized as a nodes dataframe if it was missing a "source" field, resulting in a very confusing error message "id field is required for nodes dataframe" instead of a more sensible error message about the missing source field.

[CLAassistant]

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[lovasoa]

Additionally, I'd like to suggest that "display names" of fields are considered when looking up columns instead of just "source names".

[aocenas]

I wonder if we should be a bit more smart with the categorization. There are few required columns for both the node and edges data frames and maybe we could just check them thoroughly to make sure we don't pass on an invalid data frame. Would you have time to do that? If not we can merge this PR and just leave it for later.

Additionally, I'd like to suggest that "display names" of fields are considered when looking up columns instead of just "source names".

This probably would not work well. The display names are to give columns nicer names when presented to the user. So you can for example label source/target as Client/Server for example. Because we want to give users the liberty to use any labels they want we cannot use the same thing to structurally match columns. If you are mentioning this because you cannot use rename transformations to match you data to the structure needed for the nodeGraph, we have an open PR right now to allow mapping different column names in a panel config.

[lovasoa]

Would you have time to do that?

That was a quick test I was doing, I don't really have the time to hack on grafana at the moment. SQLPage is keeping me busy. And my day job, also ;)

If you are mentioning this because you cannot use rename transformations to match you data to the structure needed for the nodeGraph, we have an open PR right now to allow mapping different column names in a panel config.

Yes, that was my problem, and mapping column names in the config would solve it even better 🙂

[aocenas]

here is the mapping pr btw #76009

Also I think this look good, will wait for the checks to pass and merge this.

[lovasoa]

Thanks !