use vector OpenTelemetry to send data to Seq

[BlueHtml]

Hello,

I am using vector to send data to Seq via the OpenTelemetry sink. When using the protobuf encoding, it requires filling in desc_file and message_type.

Could you please advise on how these fields should be configured? What values should be provided for desc_file and message_type in this context?

[nblumhardt]

Hi @BlueHtml, thanks for dropping us a line.

The "short" answer is - desc_file will be the result of compiling one of the protocol buffer definitions from https://github.com/open-telemetry/opentelemetry-proto - likely collector/logs/v1/logs_service.proto. And message_type will be the name of the request message in that definition, e.g. something like opentelemetry.proto.collector.logs.v1.ExportLogsServiceRequest.

A longer answer - I've had a skim through what I can find about OTLP support in Vector, and although I could easily be missing something important, what's there seems very, very minimal: the OTLP sink requires manually mapping your events into the precise schema required by OTLP, and then mapping those into the encoding expected by the receiver. That this is possible is kinda cool, but it's not so much an OTLP sink as an HTTP client you can build an OTLP-compatible encoding on. Looks like hard work.

OTLP logs and traces support is still marked as incomplete in Vector; until it'd done, you might be better off just targeting the simple newline-delimited JSON format supported by Seq's /ingest/clef endpoint:

https://docs.datalust.co/docs/posting-raw-events#compact-json-format

There's an example showing how this would be done with Fluent Bit (roughly analogous to Vector) here, in case it helps:

https://blog.datalust.co/tailing-a-log-file-or-folder-with-fluent-bit-and-seq/#shipping-to-seq