Record telemetry for nimbus experiments fetching

[ionutbedregeanu]

For #6847
Add a timespan to know how much it takes to download the experiments
No tests, screenshots, accessibility required

Pull Request checklist

• Tests: This PR includes thorough tests or an explanation of why it does not
• Screenshots: This PR includes screenshots or GIFs of the changes made or an explanation of why it does not
• Accessibility: The code in this PR follows accessibility best practices or does not include any user facing features. In addition, it includes a screenshot of a successful accessibility scan to ensure no new defects are added to the product.

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[ionutbedregeanu]

Request for data collection review form

All questions are mandatory. You must receive a review from a data steward peer on your responses to these questions before shipping new data collection.

1) What questions will you answer with this data?
How much it takes to fetch the nimbus experiments?

2) Why does Mozilla need to answer these questions? Are there benefits for users? Do we need this information to address product or business requirements?
This is needed to analyze feature usage and possible feature improvements.

3) What alternative methods did you consider to answer these questions? Why were they not sufficient?
This is the only way.

4) Can current instrumentation answer these questions?
No. We need a new specific event for a specific app feature.

5) List all proposed measurements and indicate the category of data collection for each measurement, using the Firefox data collection categories found on the Mozilla wiki.

Note that the data steward reviewing your request will characterize your data collection based on the highest (and most sensitive) category.

Measurement Description	Data Collection Category	Tracking Bug #
Nimbus experiments timespan	Category 1	https://github.com//issues/6847

6) How long will this data be collected? Choose one of the following:
Expiry for capturing data is set to release version 112

7) What populations will you measure?
All release channels and locales.

8) If this data collection is default on, what is the opt-out mechanism for users?
Users can opt out of data collection by disabling Usage and technical data from Settings -> Privacy and security -> Data choices.

9) Please provide a general description of how you will analyze this data.
Glean

10) Where do you intend to share the results of your analysis?
Only on Glean, mobile teams, and BD have internal access.

12) Is there a third-party tool (i.e. not Telemetry) that you are proposing to use for this data collection?
No.

[ionutbedregeanu]

successful_fetch should be renamed and converted to an event which should contains information about the state(failed or not), but also about the internet connection(if the device is connected to internet or not).
@Amejia481 @jhugman What do you think about this?

[Amejia481]

successful_fetch should be renamed and converted to an event which should contains information about the state(failed or not), but also about the internet connection(if the device is connected to internet or not). @Amejia481 @jhugman What do you think about this?

I think a boolean it's sufficient as long as we report true when we are able to fetch the experiments and false otherwise.

[jhugman]

I'm not convinced of the utility of the successfulFetch event, so suggest you remove it.

Also: could you amend the data review request to make the data category "Category 1: Technical". Edit: I see you've done the right thing in the metrics.yaml!

Otherwise, this is nice, well done. Thank you.

[Amejia481]

Having data to set a good default was the principal point, but we also wanted to have an overview idea of how many users could get/fail to fetch based on #6847 requirements. Let's not block this we could do a follow up if it's needed.

[travis79]

Data Review

1. Is there or will there be documentation that describes the schema for the ultimate data set in a public, complete, and accurate way?

Yes, through the metrics.yaml file and the Glean Dictionary.

2. Is there a control mechanism that allows the user to turn the data collection on and off?

Yes, through the "Send Usage Data" preference in the application settings.

3. If the request is for permanent data collection, is there someone who will monitor the data over time?

N/A, collection to end in v112

4. Using the category system of data types on the Mozilla wiki, what collection type of data do the requested measurements fall under?

Category 1, Technical data

5. Is the data collection request for default-on or default-off?

Default-on

6. Does the instrumentation include the addition of any new identifiers (whether anonymous or otherwise; e.g., username, random IDs, etc. See the appendix for more details)?

No

7. Is the data collection covered by the existing Firefox privacy notice?

Yes

8. Does the data collection use a third-party collection tool?

No

Result

data-review+

[travis79]

data-review+