Data Download Server

Spring Boot service for downloading (bio)measurement data via the QBiC download-API.

The service is configured via an external application.properties file. A commented, fully-documented template is available at rest-api/src/dist/application.properties.

Spring Boot looks for application.properties relative to the process working directory (the directory you are in when you launch java), not relative to the JAR file's own location. If you just drop the file "next to the JAR" it is very easy for Spring to not find it — that happens whenever the JAR is launched from a different directory (or under systemd / a service manager that does not set the working directory).

To make loading deterministic, always pass the file by absolute path on the command line:

java -jar /opt/app/rest-server-1.3.0.jar \
  --spring.config.additional-location=/opt/app/application.properties

Use --spring.config.additional-location (not --spring.config.location) so the bundled defaults inside the JAR are still used for any key the external file does not set. The file: prefix is optional when the path is absolute.

Alternatively, when running under systemd, set WorkingDirectory so the file is found relative to it:

[Service]
WorkingDirectory=/opt/app
ExecStart=/usr/bin/java -jar /opt/app/rest-server-1.3.0.jar

Spring Boot's property precedence still applies, so specific values can be overridden without editing the file, e.g. SERVER_PORT=9000 java -jar rest-server.jar. The env var wins over the external file. The bundled application.properties inside the JAR also still supports the original environment-variable placeholders for backward compatibility.

• JDK 21
• Maven 3.x

The project is a multi-module Maven build:

data-download-server (POM parent)
├── zip                        (library)
├── measurement-provider       (library)
├── storage-provider           (library)
├── openbis-connector          (library)
└── rest-api                   (Spring Boot application "rest-server")

The four library modules are not standalone services - they are dependencies of the Spring Boot application in rest-api. Building a package compiles every module and bundles all four libraries into a single executable JAR.

From the project root:

# Build everything, including tests
mvn package

# Build everything, skip tests (faster, for a release artifact)
mvn package -DskipTests

This produces one deployable artifact:

rest-api/target/rest-server-<version>.jar

The -am flag ("also make") builds rest-api together with all upstream modules it depends on - so this produces the same deployable JAR, but skips nothing it needs:

mvn -pl rest-api -am package

mvn -pl rest-api -am clean package

mvn deploy

Publishes all modules to the QBiC Nexus repository configured in distributionManagement.

The whole project uses one version, defined in one place: the <revision> property in the root pom.xml. All modules inherit this version and their build artifacts are named accordingly (e.g. rest-server-1.3.0.jar).

To change the project version, edit the single property:

<properties>
  <revision>1.3.0</revision>
</properties>

There is no per-module <version> anywhere - child POMs reference the parent via ${revision} and inter-module dependencies via ${project.version}, so a bump is applied consistently to every module in one edit. The release workflow bumps this property automatically (.github/workflows/create-release.yml).

Run the server and visit http://localhost:8090/swagger-ui.html (port depends on your configuration; default 8090).