Serialization Fails for u64 Fields Due to Incoming String Values in OpenTelemetry Metrics

[nikhilsinhaparseable]

I am using the opentelemetry-proto crate to serialize incoming OpenTelemetry metrics data. The crate defines certain fields (count, bucket_counts under HistogramDataPoint) as u64. However, the OpenTelemetry exporter sends these fields as strings, which leads to serialization failures.

This mismatch between the data types in the crate and the incoming data prevents successful serialization of metrics.

Sample JSON
otel-metrics-histogram.json

Similar issue is found in the ExponentialHistogramDataPoint

[cijothomas]

the OpenTelemetry exporter sends these fields as strings, which leads to serialization failures.

Which exporter are you referring to?

[nikhilsinhaparseable]

I am using otel collector in opentelemetry-demo to send the otel logs, metrics and traces to Parseable.

[lalitb]

As per the proto-json conversion standard, u64 should be serialized to string - https://protobuf.dev/programming-guides/json/. So i believe, opentelemetry-proto is doing it correctly?

[nikhilsinhaparseable]

I can see that the serialization to string is happening for the fields where below is available in the crate but this feature is not available for the mentioned fields.

#[cfg_attr( feature = "with-serde", serde( serialize_with = "crate::proto::serializers::serialize_u64_to_string", deserialize_with = "crate::proto::serializers::deserialize_string_to_u64" ) )]

[lalitb]

I can see that the serialization to string is happening for the fields where below is available in the crate but this feature is not available for the mentioned fields.

#[cfg_attr( feature = "with-serde", serde( serialize_with = "crate::proto::serializers::serialize_u64_to_string", deserialize_with = "crate::proto::serializers::deserialize_string_to_u64" ) )]

Yes, I did realize it afterwards, and have done changes locally to test before raising PR here -
https://github.com/lalitb/opentelemetry-rust/pull/44/files

[nikhilsinhaparseable]

@lalitb I see similar issue in SummaryDataPoint for the field quantile_values
as the fields quantile and value fields in the ValueAtQuantile struct are f64 data type but the data from the collector is somethings like this -

below is the sample JSON with summary metrics -
otel-metrics-summary.json