build: support running Maven with -T1C - #2407
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Several `integration-tests` modules consume the output of other reactor modules without declaring a dependency on them. Maven derives the reactor build order solely from directly declared dependencies, so it does not know that those modules must be built first; serial builds happen to work only because of the module ordering. As a result `mvn -T1C package` races, and `mvn -pl <module> -am` leaves the producing modules out of the reactor altogether. `it-spring-boot-smoke-test` receives `prometheus-metrics-core` only transitively, through `micrometer-registry-prometheus`, so neither `mvn -T1C package` nor `mvn -pl integration-tests/it-spring-boot-smoke-test -am` resolves the snapshot. The dependency is declared with the exclusion that `micrometer-registry-prometheus` applies, leaving the resolved set of artifacts, their versions and their scopes unchanged. `it-exporter-test` and `it-no-protobuf-test` run their sample applications from the shaded jars that the `it-exporter-*-sample` and `it-exporter-no-protobuf` modules leave in `target`, a dependency that `ExporterTest` expresses only as a relative filesystem path. The sample modules are therefore declared as test dependencies. Signed-off-by: Stephan Schroevers <stephan.schroevers@teampicnic.com>
Port 4317 is the default OTLP port, so this test fails on any machine that runs a collector. It also collides with itself: `prometheus-metrics-exporter-opentelemetry-shaded` compiles and runs this module's test sources, so the test executes twice per build, concurrently under `mvn -T`. Signed-off-by: Stephan Schroevers <stephan.schroevers@teampicnic.com>
Stephan202
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jaydeluca and
zeitlinger
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August 21, 2026 21:42
Stephan202
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-T1C-T1C
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These two changes enable reliably building multiple Maven modules concurrently with
mvn -T. On my laptop-T1Creducesmvn clean installbuild time from 04:03 to 01:29 minutes.Summary of changes:
ExemplarTestcan be executed twice concurrently (once against the shaded artifact). This change also allows one to build the project on a machine that actually runs an OLTP collector.The changes are split across two commits with suitable commit messages, so that rebase-and-merge is possible.