docs: update progressive rollout docs

[Light2Dark]

Description

Update the example used and add a description of how the configuration works. (updated)

Closes issue(s)

Resolve #2452

Checklist

• I have tested this code
• I have added unit test to cover this code
• I have updated the documentation (README.md and /website/docs)
• I have followed the contributing guide

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[Light2Dark]

Hey @thomaspoignant , I faced this issue and wanted to contribute to the docs. I think it might be worth to explain a little more on changing the percentage field. However, it is unintuitive. The following is my proposal to be added to the Example section:

Using the percentage field (advanced)

If you do not intend to completely rollout a feature, you can modify the percentage field.

    progressiveRollout:
      initial:
        variation: variationA
        percentage: 20   
        date: 2024-01-01T05:00:00.100Z
      end:
        variation: variationB
        percentage: 80
        date: 2024-01-05T05:00:00.100Z

• Before the initial date, the flag will return variationB 20% of the time and variationA 80% of the time.
• Between the initial and end date, the flag will progressively change from returning variationA to variationB.
• After the end date, the flag will return variationB 80% of the time and variationA 20% of the time.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.56%. Comparing base (a680901) to head (f394983).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   85.56%   85.56%           
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  Files         103      103           
  Lines        3816     3816           
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  Hits         3265     3265           
  Misses        425      425           
  Partials      126      126           

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[thomaspoignant]

@Light2Dark thanks a lot for this improvement of the documentation this is really great.

I agree that your proposal for the example is better to understand how it works, just to be sure you want to have 2 different examples? One without percentage `(which means that we go from 0 to 100) and one with it?
I like your proposal, the bullet list helps a lot to understand better how it works.

The only thing I would change is the Configuration fields table that is not reflecting the format, I would prefer to have an entry for initial and one for end.

[thomaspoignant]

We probably need to change this table with explaining what should be in initial and end.

[Light2Dark]

I agree that your proposal for the example is better to understand how it works, just to be sure you want to have 2 different examples? One without percentage `(which means that we go from 0 to 100) and one with it? I like your proposal, the bullet list helps a lot to understand better how it works.

Yeap, 2 examples. One is a simple use case, and another for more advanced use. Let me make some changes and you could review then :)

The only thing I would change is the Configuration fields table that is not reflecting the format, I would prefer to have an entry for initial and one for end.

Noted, let me add to this.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud