feat(sample transform): add sample_rate_key config option

[dekelpilli]

This PR adds an option, sample_rate_key, to the sample transform, where leaving it empty should cause this value to be omitted. The new default is the same as the old hard-coded value (sample_rate), so this should not be a breaking change.

[bits-bot]

All committers have signed the CLA.

[dekelpilli]

I tried merging the latest changes to fix the conflicts, but I found there were a bunch of issues and I don't have the capacity to take that on at the moment, so I've reverted for now. Are there plans to merge this at some point soon-ish? If so, I might try to carve out some time to address this conflict/resulting issues.

[jszwedko]

Thanks for this @dekelpilli ! Apologies for the delayed review. It seems to have fallen through the cracks. One thing this is missing is a changelog entry. Do you mind adding one? See https://github.com/vectordotdev/vector/blob/master/changelog.d/README.md

[jszwedko]

The merge conflicts are pretty trivial, but there are actually a number of compilation errors here to resolve. Do you mind taking a look? Apologies again that this wasn't reviewed sooner. I'm happy to keep an eye on this and merge it when it is ready.

[dekelpilli]

Yeah, I realised later that the issue was that I wasn't able to compile the version I had forked locally (regardless of my changes), and now that I can, I can see the other compilation issues. I'll try to get this ready soon and hopefully it can be merged before 0.43.

[jszwedko]

Thanks @dekelpilli ! Could you do a couple of more things:

• Run cargo fmt
• Run make generate-component-docs

And push the changes? I started to, but I lack permissions to push to this branch.

[dekelpilli]

I've run cargo fmt, but make generate-component-docs does not seem to change website/cue/reference/components/transforms/base/sample.cue for some reason. Do you have any insight as to why that would be?

Also, I had ticked "Allow edits and access to secrets by maintainers" so I'm not sure why you didn't have access, but I've added you explicitly now anyway.

[jszwedko]

Weird, it still won't let me edit this branch. I wonder if there is something special about the default branch (master) of your fork. Can you apply this diff?

772554213b - (HEAD -> dekelpilli/master) regen docs (2 minutes ago) <Jesse Szwedko>
diff --git a/website/cue/reference/components/transforms/base/sample.cue b/website/cue/reference/components/transforms/base/sample.cue
index d6b573e409..fd698ecf7b 100644
--- a/website/cue/reference/components/transforms/base/sample.cue
+++ b/website/cue/reference/components/transforms/base/sample.cue
@@ -48,4 +48,12 @@ base: components: transforms: sample: configuration: {
 			1500,
 		]
 	}
+	sample_rate_key: {
+		description: "The event key in which the sample rate is stored. If set to an empty string, the sample rate will not be added to the event."
+		required:    false
+		type: string: {
+			default: "sample_rate"
+			examples: ["sample_rate"]
+		}
+	}
 }

[jszwedko]

Thanks! I was able to make a bit more progress on pushing after accepting your invite to collaborate but I couldn't quite get the local branch tracking right.