Document network access limitations preventing integration tests

[Copilot]

Investigation revealed that while Maven/Gradle repositories are accessible, DNS resolution for external hosts is blocked in the CI environment. Integration tests requiring RIR database downloads fail with UnknownHostException for ftp.{arin,ripe,apnic,afrinic,lacnic}.net.

Changes

Documentation

• Added NETWORK_ACCESS_INVESTIGATION.md with DNS resolution test results
• Updated TEST_COVERAGE.md to explain network constraints and how to run integration tests manually

Verification

$ ping google.com
ping: google.com: No address associated with hostname

$ curl https://www.google.com  
curl: (6) Could not resolve host: www.google.com

// Integration test fails with:
java.net.UnknownHostException: ftp.arin.net
  at sun.net.ftp.impl.FtpClient.doConnect(FtpClient.java:1064)

Coverage Architecture

• 71% coverage: Unit tests (business logic, fast, no network)
• 29% gap: Integration code (FTP downloads, slow, requires DNS)

The 2 integration tests (Ip2Asn2CcIncludeFilterPolicyTest, Ip2Asn2CcExcludeFilterPolicyTest) are valid but require unrestricted network access to download ~200MB of RIR data from 5 FTP servers.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• ftp.afrinic.net
  • Triggering command: /usr/lib/jvm/temurin-8-jdk-amd64/bin/java /usr/lib/jvm/temurin-8-jdk-amd64/bin/java -Djava.security.manager=worker.org.gradle.process.internal.worker.child.BootstrapSecurityManager -Dorg.gradle.native=false -javaagent:build/tmp/expandedArchives/org.jacoco.agent-0.8.1.jar_edqovih8ve5wrctm2ogx02j98/jacocoagent.jar=destfile=build/jacoco/test.exec,append=true,inclnolocationclasses=false,dumponexit=true,output=file,jmx=false -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -ea -cp /home/REDACTED/.gradle/caches/4.0/workerMain/gradle-worker.jar worker.org.gradle.process.internal.worker.GradleWorkerMain 'Gradle Test Executor 1' (dns block)
• ftp.apnic.net
  • Triggering command: /usr/lib/jvm/temurin-8-jdk-amd64/bin/java /usr/lib/jvm/temurin-8-jdk-amd64/bin/java -Djava.security.manager=worker.org.gradle.process.internal.worker.child.BootstrapSecurityManager -Dorg.gradle.native=false -javaagent:build/tmp/expandedArchives/org.jacoco.agent-0.8.1.jar_edqovih8ve5wrctm2ogx02j98/jacocoagent.jar=destfile=build/jacoco/test.exec,append=true,inclnolocationclasses=false,dumponexit=true,output=file,jmx=false -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -ea -cp /home/REDACTED/.gradle/caches/4.0/workerMain/gradle-worker.jar worker.org.gradle.process.internal.worker.GradleWorkerMain 'Gradle Test Executor 1' (dns block)
• ftp.arin.net
  • Triggering command: /usr/lib/jvm/temurin-8-jdk-amd64/bin/java /usr/lib/jvm/temurin-8-jdk-amd64/bin/java -Djava.security.manager=worker.org.gradle.process.internal.worker.child.BootstrapSecurityManager -Dorg.gradle.native=false -javaagent:build/tmp/expandedArchives/org.jacoco.agent-0.8.1.jar_edqovih8ve5wrctm2ogx02j98/jacocoagent.jar=destfile=build/jacoco/test.exec,append=true,inclnolocationclasses=false,dumponexit=true,output=file,jmx=false -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -ea -cp /home/REDACTED/.gradle/caches/4.0/workerMain/gradle-worker.jar worker.org.gradle.process.internal.worker.GradleWorkerMain 'Gradle Test Executor 1' (dns block)
• ftp.lacnic.net
  • Triggering command: /usr/lib/jvm/temurin-8-jdk-amd64/bin/java /usr/lib/jvm/temurin-8-jdk-amd64/bin/java -Djava.security.manager=worker.org.gradle.process.internal.worker.child.BootstrapSecurityManager -Dorg.gradle.native=false -javaagent:build/tmp/expandedArchives/org.jacoco.agent-0.8.1.jar_edqovih8ve5wrctm2ogx02j98/jacocoagent.jar=destfile=build/jacoco/test.exec,append=true,inclnolocationclasses=false,dumponexit=true,output=file,jmx=false -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -ea -cp /home/REDACTED/.gradle/caches/4.0/workerMain/gradle-worker.jar worker.org.gradle.process.internal.worker.GradleWorkerMain 'Gradle Test Executor 1' (dns block)
• ftp.ripe.net
  • Triggering command: /usr/lib/jvm/temurin-8-jdk-amd64/bin/java /usr/lib/jvm/temurin-8-jdk-amd64/bin/java -Djava.security.manager=worker.org.gradle.process.internal.worker.child.BootstrapSecurityManager -Dorg.gradle.native=false -javaagent:build/tmp/expandedArchives/org.jacoco.agent-0.8.1.jar_edqovih8ve5wrctm2ogx02j98/jacocoagent.jar=destfile=build/jacoco/test.exec,append=true,inclnolocationclasses=false,dumponexit=true,output=file,jmx=false -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -ea -cp /home/REDACTED/.gradle/caches/4.0/workerMain/gradle-worker.jar worker.org.gradle.process.internal.worker.GradleWorkerMain 'Gradle Test Executor 1' (dns block)
• google.com
  • Triggering command: /usr/bin/ping ping -c 2 google.com (dns block)
• www.google.com
  • Triggering command: /usr/bin/curl curl -I REDACTED (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Improve test coverage</issue_title>
<issue_description>Generally improve test coverage, reaching 95% (if possible).</issue_description>

<agent_instructions>I don't know whether the repo has any plugins or a way to know the current test coverage (through reports). If it doesn't have, please add an open source solution for that.

The goal is that the repo is absolutely greatly covered with tests.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Improve test coverage #1

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