Added opentracing-jdbc

[whiskeysierra]

Description

Motivation and Context

Part of #328

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.

[lukasniemeier-zalando]

Is it an issue that in case the decorator fails (i.e. exception thrown in onError) that we never gonna call span.finish()?

[whiskeysierra]

True. Good catch.

[whiskeysierra]

Now I'm curious how vendors/implementations deal with that. Technically it could be the source of a memory leak to start but never finish spans. Ideally tracers would keep only weak references to spans and discard them.

[whiskeysierra]

I added a try-finally around onError but technically the onQuery could fail also and what to do with the span then? Discard (if, how)? Ignore and finish as usual?

[whiskeysierra]

If I'm reading LightStep's code correctly then they don't keep a strong reference to it and abandoned spans would be garbage collected.

[whiskeysierra]

Question regarding errors during onQuery still stands though.

[lukasniemeier-zalando]

If onQuery fails, is afterQuery (and hence onError) called?

[whiskeysierra]

https://github.com/ttddyy/datasource-proxy/blob/c1f62baf6fa13014982e8098fc3a22ffb592892d/src/main/java/net/ttddyy/dsproxy/proxy/StatementProxyLogic.java#L307-L396

beforeQuery is running outside the try-finally that would execute the afterQuery.

[lukasniemeier-zalando]

👍

[whiskeysierra]

I have to double check but if my memory is correct then no.

…

On Tue, 26 Nov 2019, 22:17 lukasniemeier-zalando, ***@***.***> wrote: ***@***.**** commented on this pull request. ------------------------------ In opentracing-jdbc/opentracing-jdbc/src/main/java/org/zalando/opentracing/jdbc/TracingQueryExecutionListener.java <#332 (comment)> : > + + decorator.onQuery(span, statement, queries); + + info.addCustomValue(SPAN, span); + } + + @OverRide + @SneakyThrows(SQLException.class) + public void afterQuery(final ExecutionInfo info, final List<QueryInfo> queries) { + final Span span = info.getCustomValue(SPAN, Span.class); + + if (!info.isSuccess()) { + final Statement statement = info.getStatement(); + final Throwable error = info.getThrowable(); + + decorator.onError(span, statement, error); If onQuery fails, is afterQuery (and hence onError) called? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#332?email_source=notifications&email_token=AADI7HKRWV5DX7C3ORCPT7TQVWHAHA5CNFSM4JRPHNP2YY3PNVWWK3TUL52HS4DFWFIHK3DMKJSXC5LFON2FEZLWNFSXPKTDN5WW2ZLOORPWSZGOCNCQKCI#discussion_r350984404>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AADI7HIDCPMHWVQXMZJDTWTQVWHAHANCNFSM4JRPHNPQ> .

[lukasniemeier-zalando]

👍