Late in 2018 we landed a basic implementation of the Telemetry multi-store. Telemetry multi-store allows the re-use of probes across multiple pings, with each ping having their own schedule to be sent. It ships in Firefox 65.
Overview The lifetime of Telemetry probes (scalars & histograms) and thus their reset cycle were previously closely tied to the main ping. Custom pings had to keep track of their own data or copy out data from Telemetry probes. Multi-store will now make it easier to do this without custom code to store the probe data. This way data collections can still be in Histograms.json, Scalars.yaml, and Events.yaml and benefit from documentation, expiration, and tool integration (like the Probe Dictionary) but be used by custom pings that have custom client data lifetime requirements. Technical details Probes (scalars & histograms) can now specify additional stores through the “record_into_store” property, defaulting to a single “main” store (used for the main ping). Recording will happen into every store automatically. Additionally we provide new APIs for accessing snapshots of the data: getSnapshotForHistograms(storeName, clearStore) getSnapshotForKeyedHistograms(storeName, clearStore) getSnapshotForScalars(storeName, clearStore) getSnapshotForKeyedScalars(storeName, clearStore) Custom pings will add their store to the probes they want to include and when assembling the ping payload call one of the above snapshot methods to get the data (and clear it). You can find a more detailed blog post with some sample code here: https://fnordig.de/2019/01/22/multi-store-custom-telemetry-with-shared-data/ <https://fnordig.de/2019/01/22/multi-store-custom-telemetry-with-shared-data/> Telemetry APIs The Firefox Telemetry APIs now include: - Privileged Firefox JavaScript through nsITelemetry <https://searchfox.org/mozilla-central/source/toolkit/components/telemetry/nsITelemetry.idl>, including the new snapshot APIs - Submitting custom pings <https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/collection/custom-pings.html> - C++ code through Telemetry.h <https://searchfox.org/mozilla-central/source/toolkit/components/telemetry/core/Telemetry.h> - WebExtensions through browser.telemetry <https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/collection/webextension-api.html> - Specific in-product Mozilla websites through Hybrid Content Telemetry <https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/collection/hybrid-content.html> - (newly introduced) shared test utilities in TelemetryTestUtils <https://searchfox.org/mozilla-central/source/toolkit/components/telemetry/tests/utils/TelemetryTestUtils.jsm> As always, please do reach out if you have any questions or concerns. You can find us in #telemetry on IRC, #fx-metrics on Slack and the fx-data-dev <https://mail.mozilla.org/listinfo/fx-data-dev> mailing list. Your Friendly Neighbourhood Firefox Telemetry Team (:janerik, gfritzsche, :Dexter, :chutten, :travis_) _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
