feat(new transform): add a simple delay transform by esensar · Pull Request #25407 · vectordotdev/vector

esensar · 2026-05-11T08:53:52Z

Summary

Adds a new transform which delays each event in the pipeline by a fixed duration.

Vector configuration

sources:
  demo_logs_test:
    type: "demo_logs"
    format: "json"

transforms:
  delay_transform:
    inputs: ["demo_logs_test"]
    type: "delay"
    delay_per_event: 5

sinks:
  console:
    inputs: ["delay_transform"]
    target: "stdout"
    type: "console"
    acknowledgements:
      enabled: false
    encoding:
      codec: "json"

How did you test this PR?

Ran the included test and ran Vector with the above configuration to confirm that events were correctly delayed.

Change Type

Is this a breaking change?

Yes
No

Does this PR include user facing changes?

Yes. Please add a changelog fragment based on our guidelines.
No. A maintainer will apply the no-changelog label to this PR.

References

Closes: Feature request: sleep() function for inserting delay into processing chain #22146

Notes

Please read our Vector contributor resources.
Do not hesitate to use @vectordotdev/vector to reach out to us regarding this PR.
Some CI checks run only after we manually approve them.
- We recommend adding a pre-push hook, please see this template.
- Alternatively, we recommend running the following locally before pushing to the remote branch:
  - make fmt
  - make check-clippy (if there are failures it's possible some of them can be fixed with make clippy-fix)
  - make test
After a review is requested, please avoid force pushes to help us review incrementally.
- Feel free to push as many commits as you want. They will be squashed into one before merging.
- For example, you can run git merge origin master and git push.
If this PR introduces changes Vector dependencies (modifies Cargo.lock), please
run make build-licenses to regenerate the license inventory and commit the changes (if any). More details on the dd-rust-license-tool.

Sponsored by Quad9

Closes: vectordotdev#22146

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: c81015ff6f

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

pront

One idea worth considering is adding a VRL condition for each event in order to answer "do i want to forward this event now?". We could also add retries + exponential backoff. Non-blocking but something worth considering.

thomasqueirozb

Hi @esensar. Thanks for this! I thought about implementing this myself a couple of times before.

This is missing website/cue/reference/components/transforms/delay.cue and website/content/en/docs/reference/configuration/transforms/delay.md

esensar · 2026-05-14T07:46:43Z

One idea worth considering is adding a VRL condition for each event in order to answer "do i want to forward this event now?". We could also add retries + exponential backoff. Non-blocking but something worth considering.

That sounds good. This is probably too simple the way it is (even though it could probably be combined with other components to achieve some of these things).

I am not sure about retries though. What would we be retrying here?

Co-authored-by: Thomas <thomasqueirozb@gmail.com>

esensar · 2026-05-14T07:47:39Z

Hi @esensar. Thanks for this! I thought about implementing this myself a couple of times before.

This is missing website/cue/reference/components/transforms/delay.cue and website/content/en/docs/reference/configuration/transforms/delay.md

I just ran generate-component-docs, I forget that new components need some new files too. I will update.

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 7d93ced0b2

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

pront · 2026-05-14T13:58:06Z

I am not sure about retries though. What would we be retrying here?

@esensar some condition until it is evaluates to true and the event can be forwarded

esensar · 2026-05-14T14:38:56Z

I am not sure about retries though. What would we be retrying here?

@esensar some condition until it is evaluates to true and the event can be forwarded

Oh, alright, that is interesting. I will see about adding that in too.

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: cc922cb2ff

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

esensar · 2026-05-14T15:22:29Z

I am not sure about retries though. What would we be retrying here?

@esensar some condition until it is evaluates to true and the event can be forwarded

What do we do if it never evaluates to true? Or do we just leave that to the user to ensure? (with some warning probably)

esensar · 2026-05-14T17:56:46Z

I am not sure about retries though. What would we be retrying here?

@esensar some condition until it is evaluates to true and the event can be forwarded

I just realized that the static condition that I added is not useful at all, since that functionality can be provided by filter transform before the delay transform, while that delay until some condition is met can be more useful.

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 03c62f57fa

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

chatgpt-codex-connector · 2026-05-14T18:36:42Z

+                                            while capacity.get() <= self.queue.len() && let Some(next) = self.queue.next().await {
+                                                yield next.into_inner();


Apply delay condition when unblocking a full queue

When queue_capacity is set and the default overflow_strategy = "block" is used, this path drains an expired queued event directly to the output to make room for the new event. That bypasses the delay_until_condition.check(...) logic used in the normal queue-expiry branch, so a queued event is emitted as soon as its first delay expires even if delay_until_condition is still false whenever the queue is full and another input event arrives.

Useful? React with 👍 / 👎.

feat(new transform): add a simple delay transform

c81015f

Closes: vectordotdev#22146

esensar requested review from a team as code owners May 11, 2026 08:53

github-actions Bot added domain: transforms Anything related to Vector's transform components domain: external docs Anything related to Vector's external, public documentation docs review on hold The documentation team reviews PRs only after a PR is approved by the COSE team. labels May 11, 2026

Add changelog entry

eac8b7d

chatgpt-codex-connector Bot reviewed May 11, 2026

View reviewed changes

Comment thread src/transforms/delay.rs

Prevent polling input_rx when done = true

bf48d60

brett0000FF approved these changes May 11, 2026

View reviewed changes

pront reviewed May 13, 2026

View reviewed changes

thomasqueirozb reviewed May 13, 2026

View reviewed changes

Comment thread src/transforms/delay.rs Outdated

thomasqueirozb added transform: new Request or implementation of a new transform meta: awaiting author Pull requests that are awaiting their author. labels May 13, 2026

Update src/transforms/delay.rs

3bddeee

Co-authored-by: Thomas <thomasqueirozb@gmail.com>

github-actions Bot removed the meta: awaiting author Pull requests that are awaiting their author. label May 14, 2026

Add missing docs files

7d93ced

chatgpt-codex-connector Bot reviewed May 14, 2026

View reviewed changes

Comment thread src/transforms/delay.rs

Add delay condition

be78886

Add support for queue capacity to prevent unbounded memory growth

cc922cb

chatgpt-codex-connector Bot reviewed May 14, 2026

View reviewed changes

Comment thread src/transforms/delay.rs Outdated

Emit ComponentEventsDropped on drop newest

0682b9d

esensar added 2 commits May 14, 2026 20:16

Change condition to delay_until_condition

0b9eb52

Update docs

03c62f5

chatgpt-codex-connector Bot reviewed May 14, 2026

View reviewed changes

		while capacity.get() <= self.queue.len() && let Some(next) = self.queue.next().await {
		yield next.into_inner();

Conversation

esensar commented May 11, 2026

Summary

Vector configuration

How did you test this PR?

Change Type

Is this a breaking change?

Does this PR include user facing changes?

References

Notes

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

pront left a comment

Choose a reason for hiding this comment

Uh oh!

thomasqueirozb left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

esensar commented May 14, 2026

Uh oh!

esensar commented May 14, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

pront commented May 14, 2026

Uh oh!

esensar commented May 14, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

esensar commented May 14, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

esensar commented May 14, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

chatgpt-codex-connector Bot May 14, 2026

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

esensar commented May 14, 2026 •

edited

Loading