low performance /info endpoint

The issue was found by the GC QA team while testing the /info endpoint for the entitlements service.

TC: request to https://community.gcp.gnrg-osdu.projects.epam.com/api/entitlements/v2/info under Apache JMeter with settings:

• Number of threads: 1000
• Loop count: Infinity
• Duration: 300 seconds

Result from VisualVM:

depends on the configuration of the pods.

Code with an issue:

public VersionInfo buildVersionInfo() throws IOException {
    loadBuildInfoProperties();
    loadGitProperties();
    List<ConnectedOuterService> connectedOuterServices = loadConnectedOuterServices();
    return VersionInfo.builder()
        .groupId(buildInfoProperties.getProperty("build.group"))
        .artifactId(buildInfoProperties.getProperty("build.artifact"))
        .version(buildInfoProperties.getProperty("build.version"))
        .buildTime(buildInfoProperties.getProperty("build.time"))
        .branch(gitProperties.getProperty("git.branch"))
        .commitId(gitProperties.getProperty("git.commit.id"))
        .commitMessage(gitProperties.getProperty("git.commit.message.short"))
        .connectedOuterServices(connectedOuterServices)
        .build();
  }

  private void loadGitProperties() throws IOException {
    InputStream gitStream =
        this.getClass().getResourceAsStream(versionInfoProperties.getGitPropertiesPath());
    if (gitStream != null) {
      gitProperties.load(gitStream);
    } else {
      log.error(
          "Git properties file not found by path: {}",
          versionInfoProperties.getGitPropertiesPath());
    }
  }

  private void loadGitProperties() throws IOException {
    InputStream gitStream =
        this.getClass().getResourceAsStream(versionInfoProperties.getGitPropertiesPath());
    if (gitStream != null) {
      gitProperties.load(gitStream);
    } else {
      log.error(
          "Git properties file not found by path: {}",
          versionInfoProperties.getGitPropertiesPath());
    }
  }
```

1. Strings should be constants.
2. InputStream should be closed.
3. Overwrite the logic in such a way as not to read the file every time on request and thereby reduce the IO operations.