Customization Feature for Percentile Display on Statistics Page

[FooQoo]

Overview

This PR introduces a feature that allows users to freely specify which percentiles are displayed on the statistics page of Locust. Additionally, minor modifications are made to align the display content of the statistics page with that of the charts page.

Implementation Details

1. A new variable PERCENTILES_TO_STATISTICS is added, enabling users to specify the percentiles displayed on the statistics page.
2. The specified values in PERCENTILES_TO_STATISTICS will be reflected in both the existing UI and the modern UI of Locust.
3. Add the column control feature for the modern UI.

Display Modifications

• Changed "Median (ms)" to "50%ile (ms)".
• Changed "90%ile (ms)" to "95%ile (ms)".

Background

Based on Issue #2546, this enhancement aims to improve the customizability of the statistics page and ensure consistency with the charts page. This will enable users to analyze data more effectively.

[cyberw]

I was thinking this could be even nicer to have controlled in the UI at run time?

Is _TO_STATICS an abbreviation of _TO_STATISTICS? Looks weird to my eyes :)

Median is more easily understood by people than 50%ile. Although tbh, I think we might want to remove it from the default anyways, so maybe it doesnt matter and we could just choose whatever is less complex code.

Build fails because of code formatting.

What do you think @andrewbaldwin44 ?

[cyberw]

Does the test actually cover the use of PERCENTILES_TO_STATICS?

[andrewbaldwin44]

Hey looking good! I also had the thought (and I'm not sure if this is what you meant @cyberw) that it could be nice to be able to control the columns in the web UI. Something like this:

The nice part about PERCENTILES_TO_STATICS is that it allows users to set the percentiles they care about and potentially saves some performance

[andrewbaldwin44]

Yeah maybe we can add some tests for PERCENTILES_TO_STATISTICS (at least in the backend) and some validation to ensure that the statistics provided are valid? Similar to what we do with PERCENTILES_TO_CHART

[FooQoo]

@cyberw @andrewbaldwin44

Thank you for your positive feedback and insightful suggestions. Here is my response to the points you have raised:

Addressed Items

1. Concern About Variable Name and Build Failure: These issues have already been addressed in a recent commit. I corrected the variable name from _TO_STATICS to _TO_STATISTICS and resolved the build failure issue by applying the ruff formatter.

Next Actions

1. Test Coverage for PERCENTILES_TO_STATISTICS: I plan to add tests to cover this new feature to ensure its proper functioning and integration.

Regarding Your Suggestions

1. On 'Median' vs '50%ile' Clarity: Thank you for your valuable opinion. I am considering keeping 'Median' as the default statistical measure and not including '50%ile' in the percentiles. This aligns with your suggestion and I believe it will make the statistics more user-friendly.

2. Column Control in Web UI: I will try implementing the proposed mechanism that allows users to control the display columns directly in the Web UI.

Additional Question

Regarding the support for the legacy UI, I have already implemented some features. Should I consider removing these to focus solely on the modern UI, or would it be more beneficial to maintain them? Your guidance on this matter would be greatly appreciated.

[FooQoo]

Added unit tests for normalize_decimal and integration tests, also reverted percentile display from 50%ile back to median.

[cyberw]

Suggest you change this to "list of response time percentiles to show in the statistics table"

And maybe remove "The" from all descriptions, I dont know why that is in there :)

[cyberw]

instead maybe add something about this and PERCENTILES_TO_CHART being UI settings (just to make it clear)

[FooQoo]

@cyberw
I've updated the descriptions for PERCENTILES_TO_CHART and PERCENTILES_TO_STATISTICS as suggested.
3981277

[andrewbaldwin44]

In main.py, we have some validation to ensure the provided PERCENTILES_TO_CHART is correct:

# line 133
for percentile in stats.PERCENTILES_TO_CHART:
        if not is_valid_percentile(percentile):
            logging.error(
                "stats.PERCENTILES_TO_CHART parameter need to be float and value between. 0 < percentile < 1 Eg 0.95\n"
            )
            sys.exit(1)

Perhaps we should have this same validation for PERCENTILES_TO_STATISTICS?

[FooQoo]

Added a Column Control feature to the Web UI in a PR. Would love your feedback on it!

[andrewbaldwin44]

Awesome work with the column selector! The code and the tests look really great! :) Just a suggestion - what if we had the useSelectViewColumns hook return a new table structure with the hidden columns filtered out? This way we wouldn't have to change the table component

[FooQoo]

@andrewbaldwin44
Thanks for the feedback and the suggestion!
I've updated the useSelectViewColumns hook to return a new table structure.

I've updated the useSelectViewColumns hook to include the filterStructure function.

Now it takes a structure argument and returns a new table structure with only the visible columns, filtering out the hidden ones.
This should indeed help us avoid modifying the table component. Let me know what you think!

6458cde
c214bec

[andrewbaldwin44]

Looks awesome, nice work! 💯 @cyberw Good with you to merge?