Feature (service graph): inferred services/entities

[utrack]

Is your feature request related to a problem? Please describe

It's very useful to see all the 3rd-party services that your service is calling, even if that service does not report any traces (as it usually happens).

They might include any real 3rd parties (some SaaS), legacy systems that don't support tracing, and databases that don't report them.

Some monitoring solutions (I'm looking at Datadog specifically) support a thing called 'Inferred services' - services that don't report traces of its own, but they appear in the service list/graph as separate nodes.

Describe the solution you'd like

Display the 'inferred' services in the service graph.

There is an inferred service if:

• There is a span with the kind: client
• There's no child span
• (optional) There is some other information in the client span which lets you understand the system type (ex: there are database attributes, or the span comes from the HTTP or gRPC client)

If it's a DB, then display the namespace+hostname as a name (which will let you link many services to one node if they use the same DB), if it's an RPC - then the hostname+port will do.

Describe alternatives you've considered

No response

Additional information

Related issues:

• Display DB as an inferred service (same thing, but focuses on databases specifically): feature:add service-to-middleware relations #117

[jiekun]

I put feedback for (part of) idea in #117 (comment). For the rest of it, I really like the idea of exploring it (service graph) further — PR #117 seems to be a subset of this proposal.

That said, we have some high-priority enhancements in progress right now, so we may not be able to devote more effort to implementing this full proposal anytime soon. PRs are always welcome, though!