Now that the Glean Dictionary (https://dictionary.telemetry.mozilla.org)
has hit production, our guidance is to move away from generating
metrics.md files. The Glean Dictionary is a better solution for this task
for a couple of reasons:
1. The Glean Dictionary contains a complete reference of all metrics
and pings sent by an application (not just those defined in the
application itself, as is the case with the markdown documentation)
2. The Glean Dictionary provides additional context and links beyond
what is provided by the documentation (for example, information on
how to access metric information via BigQuery or GLAM) as well as
annotations provided by data scientists in the course of analyzing data
(see, for example, the commentary section for:
https://dictionary.telemetry.mozilla.org/apps/fenix/metrics/metrics_search_count).
This should also reduce some of the churn/burden on people when
they submit PRs, as there is no longer any need to update metrics.md
as a part of them.
This fetches the Google Advertising ID, salts it and
then applies hashing before sending a ping with it,
at startup. Hashing and salting are used in order
to prevent ourselves to correlate advertising IDs
from the same user running different products we
own off a single device. We will never send the
client_id and the Google Advertising ID in the same
ping.