[BUG] a lot of getting all indices error when open sample detector page

[ylwu-amzn]

What is the bug?
See a lot of "Error getting all indices" error when open sample detector.

How can one reproduce the bug?
Steps to reproduce the behavior:

1. Create multi node cluster with CDK
2. Create 3 sample detectors
3. Open sample-ecommerce-detector
4. See a lot of Error getting all indices error. Open browser network, see many requests of _indices?index=.

What is the expected behavior?
Just throw one error and don't sent out so many request in short time.

What is your host/environment?

• OS: Amazon Linux 2
• Version 1.3.1
• Plugins

Do you have any screenshots?

Do you have any additional context?
Add any other context about the problem.

[inidona]

we have this problem also, with our regular indices. I have this screenshot from java script console. So it seems that the browser could not process so much requests at once.

[amitgalitz]

Thanks @ylwu-amzn and @inidona for bringing this up. After an initial look the issue seems to be within these lines of code: https://github.com/opensearch-project/anomaly-detection-dashboards-plugin/blob/main/public/pages/DetectorDetail/containers/DetectorDetail.tsx#L157-L165 We have it set up to refetch indices on any changes to prop/states. The original purpose as described in the comment is to re-fetch if there are changes to the detector "(e.g., detector starts, result index recreated or user switches tabs to re-fetch detector)" however if the page is taking a while to load initially it will constantly refetch indices until the page has fully rendered and all initial prop/states changes have happened. I’ll look into a potential fix, let us know if you have suggestion or if you would like to contribute to this fix

[amitgalitz]

More specifically what is happening is that the useFetchDetectorInfo(detectorId) method is getting called in a loop until various conditions are met: https://github.com/opensearch-project/anomaly-detection-dashboards-plugin/blob/main/public/pages/CreateDetectorSteps/hooks/useFetchDetectorInfo.ts#L23. Solution would either be to change useFetchDetectorInfo() to only get called once and wait for response or to add if (!isLoadingDetector) before calling getInitialIndices() so we don't make constant network requests while detector is being fetched.