1772156 - Make all exported metrics definition types more convenient for use with serde

Status: RESOLVED FIXED

(Data Platform and Tools :: Glean: SDK, enhancement, P2)

Description

[Chris H-C :chutten|PTO (back Jan 5)]

It would be convenient for FOG if the Glean SDK would make all of CommonMetricData Deserialize so metric definition information could be parsed from a string (for the purposes of dynamic registration of metrics (JOG)).

With the power of serde remote derivation JOG may be able to get CommonMetricData to work if only Lifetime is Deserialize, but that would be less convenient.

JOG doesn't need Serialize since the serialization for artefact builds will happen at build time in a Python environment, not a Rust one. However, if we're looking ahead to Dynamic Telemetry (where definition information comes over the wire) then it might be beneficial to have Serialize as well.

What might be noteworthy is that, already, quite a few other exported metric definition types (TimeUnit, MemoryUnit, HistogramType) are convenient for use with serde, so really we're just bringing the rest of these types up to standard : )

Comment 1

[Chris H-C :chutten|PTO (back Jan 5)]

Jan-Erik, what's your opinion on me taking the most-convenient-for-FOG route and "just" deriving Serialize and Deserialize for CommonMetricData (which implies Lifetime)?

Comment 2

[Jan-Erik Rediger [:janerik] (Away until 2026-01-05)]

Go for it. You should probably add #[serde(rename_all = "lowercase")] to Lifetime when deriving Serialize.

Comment 3

[Chris H-C :chutten|PTO (back Jan 5)]

(In reply to Jan-Erik Rediger [:janerik] from comment #2)

Go for it. You should probably add #[serde(rename_all = "lowercase")] to Lifetime when deriving Serialize.

I hope that's all it needs. I added that directive for the Deserialize remote derivation I was trying to use for an all-in-JOG impl and it wasn't enough : |

Comment 4

[GitHub Bugzilla PR Linker]

Attachment: Link to GitHub pull-request: https://github.com/mozilla/glean/pull/2094

Comment 5

[Chris H-C :chutten|PTO (back Jan 5)]

chutten merged PR #2094: "bug 1772156 - Derive (De)Serialize for CMD and Lifetime" in 86be9f6.