feat(instrumentation-pg): propagate context using set application_name by mhennoch · Pull Request #3454 · open-telemetry/opentelemetry-js-contrib

mhennoch · 2026-03-26T09:29:00Z

Changes

Adds SET application_name as a context propagation mechanism, following the pattern established for SQL Server (SET CONTEXT_INFO) and Oracle (V$SESSION.ACTION).

Why SET application_name?

PostgreSQL instrumentation already supports SQL Commenter, but it has limitations:

Prepared statements -- SQL Commenter cannot be used with named/prepared queries, as the comment is baked into the statement text and every subsequent execution carries stale trace context.
Stored procedures -- SQL comments on the outer CALL statement are not visible to queries executed inside the procedure body.

SET application_name operates at the session level and avoids all of these issues.

There is ongoing discussion in the npgsql community about this not being the ideal long-term solution, but no better alternative currently exists for PostgreSQL, and getting to one will take a long time. I will also create a semconv issue about it. This feature is disabled by default, as in the other instrumentations.

Existing and related implementations

Node.js (tedious/SQL Server): opentelemetry-js-contrib#3141
Node.js (oracledb): opentelemetry-js-contrib#3226
Java (PostgreSQL): splunk-otel-java#2540
Collector: opentelemetry-collector-contrib#44868

github-actions · 2026-03-27T06:50:21Z

This package does not have an assigned component owner and is considered unmaintained. As such this package is in feature-freeze and this PR will be closed with 14 days unless a new owner or a sponsor (a member of @open-telemetry/javascript-approvers) for the feature is found. It is the responsibility of the author to find a sponsor for this feature.
Are you familiar with this package? Consider becoming a component owner.

maryliag · 2026-04-07T15:19:31Z

I haven't checked the code yet, but can you add more tests? I can see that the codecov is failing, so this will need to increase the coverage

github-actions · 2026-04-17T07:05:46Z

This package does not have an assigned component owner and is considered unmaintained. As such this package is in feature-freeze and this PR will be closed with 14 days unless a new owner or a sponsor (a member of @open-telemetry/javascript-approvers) for the feature is found. It is the responsibility of the author to find a sponsor for this feature.
Are you familiar with this package? Consider becoming a component owner.

github-actions · 2026-04-22T07:06:33Z

This package does not have an assigned component owner and is considered unmaintained. As such this package is in feature-freeze and this PR will be closed with 14 days unless a new owner or a sponsor (a member of @open-telemetry/javascript-approvers) for the feature is found. It is the responsibility of the author to find a sponsor for this feature.
Are you familiar with this package? Consider becoming a component owner.

github-actions · 2026-04-29T07:17:43Z

This package does not have an assigned component owner and is considered unmaintained. As such this package is in feature-freeze and this PR will be closed with 14 days unless a new owner or a sponsor (a member of @open-telemetry/javascript-approvers) for the feature is found. It is the responsibility of the author to find a sponsor for this feature.
Are you familiar with this package? Consider becoming a component owner.

raphael-theriault-swi

LGTM apart from the silent failure. Sorry it took so long to get a review.

raphael-theriault-swi · 2026-05-05T15:59:51Z

+          const traceparent = buildTraceparent(span);
+          if (traceparent) {
+            const setQuery = {
+              text: `SET application_name = '${traceparent}'`,
+              [INTERNAL_SET_QUERY]: true,
+            };
+            try {
+              const setResult: unknown = original.apply(this, [
+                setQuery,
+              ] as never);
+              if (setResult instanceof Promise) {
+                setResult.catch(() => {});
+              }
+            } catch {
+              // Silently ignore SET failures to avoid breaking user queries
+            }
+          }


I'd like there to be some diag warnings here on failure so it doesn't fail completely silently. Would make things a lot easier to debug for people if they're not getting correlation.

raphael-theriault-swi · 2026-05-05T16:02:25Z

    return query;
  }

  const propagator = new W3CTraceContextPropagator();


Nitpicking but this could be removed to use the newly added one at the module scope.

mhennoch requested a review from a team as a code owner March 26, 2026 09:29

github-actions Bot added pkg:instrumentation-mysql2 pkg:instrumentation-pg pkg:sql-common pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. labels Mar 26, 2026

github-actions Bot assigned maryliag Mar 26, 2026

github-actions Bot requested a review from maryliag March 26, 2026 09:29

github-actions Bot added the pkg-status:unmaintained:autoclose-scheduled label Mar 27, 2026

raphael-theriault-swi removed pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. pkg-status:unmaintained:autoclose-scheduled labels Mar 27, 2026

maryliag removed the pkg:instrumentation-mysql2 label Apr 7, 2026

mhennoch added 5 commits April 16, 2026 17:47

feat(instrumentation-pg): propagate context using set application_name

30b7662

Update tests

5394a7b

Refactor

48fcc18

Remove redundanat test

c999f7b

fix lint

fd5231e

mhennoch force-pushed the pgsetappname branch from 36cdddb to fd5231e Compare April 16, 2026 14:51

github-actions Bot added pkg:instrumentation-mysql2 pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. labels Apr 16, 2026

github-actions Bot added the pkg-status:unmaintained:autoclose-scheduled label Apr 17, 2026

maryliag removed pkg:instrumentation-mysql2 pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. pkg-status:unmaintained:autoclose-scheduled labels Apr 17, 2026

Try running with correct env

ae9a2f6

mhennoch requested a review from a team as a code owner April 21, 2026 09:17

github-actions Bot added pkg:instrumentation-mysql2 pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. labels Apr 21, 2026

mhennoch added 2 commits April 21, 2026 16:44

Try increasing the timeout for flaky test

92f7f64

dont swallow err

effc955

github-actions Bot added the pkg-status:unmaintained:autoclose-scheduled label Apr 22, 2026

try fix

0500e1e

maryliag removed the pkg:instrumentation-mysql2 label Apr 22, 2026

pichlermarc removed pkg:sql-common pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. pkg-status:unmaintained:autoclose-scheduled labels Apr 22, 2026

mhennoch added 2 commits April 28, 2026 22:27

Clean tests

a09cacf

Merge branch 'main' into pgsetappname

2f0dc6f

github-actions Bot added pkg:instrumentation-mysql2 pkg:sql-common pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. labels Apr 28, 2026

github-actions Bot added the pkg-status:unmaintained:autoclose-scheduled label Apr 29, 2026

maryliag added has:sponsor This package or feature has a sponsor that has volunteered to review PRs and respond to questions and removed pkg:instrumentation-mysql2 pkg-status:unmaintained:autoclose-scheduled labels Apr 29, 2026

pichlermarc self-assigned this Apr 29, 2026

raphael-theriault-swi self-assigned this Apr 29, 2026

raphael-theriault-swi requested changes May 5, 2026

View reviewed changes

raphael-theriault-swi removed the pkg-status:unmaintained This package is unmaintained. Only bugfixes may be acceped until a new owner has been found. label May 5, 2026

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feat(instrumentation-pg): propagate context using set application_name#3454

feat(instrumentation-pg): propagate context using set application_name#3454
mhennoch wants to merge 11 commits intoopen-telemetry:mainfrom
mhennoch:pgsetappname

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mhennoch commented Mar 26, 2026

Changes

Why SET application_name?

Existing and related implementations

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github-actions Bot commented Mar 27, 2026

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maryliag commented Apr 7, 2026

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github-actions Bot commented Apr 17, 2026

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