throws ArtifactResolutionException, ArtifactNotFoundException {
        if (artifact == null) {
            return;
        }

        if (Artifact.SCOPE_SYSTEM.equals(artifact.getScope())) {
            File systemFile = artifact.getFile();

            if (systemFile == null) {
                throw new ArtifactNotFoundException("System artifact: " + artifact + " has no file attached", artifact);

                if (org != val) {
                    dependency.setClassifier(val);
                    dependency.clearManagementKey();
                }
                // Scope
                org = dependency.getScope();
                val = interpolate(org);
                if (org != val) {
                    dependency.setScope(val);
                }
                // SystemPath

	if accessKeyID == "" || secretAccessKey == "" {
		return errors.New("Presign cannot be generated without access and secret keys")
	}

	region := globalSite.Region()
	date := UTCNow()
	scope := getScope(date, region)
	credential := fmt.Sprintf("%s/%s", accessKeyID, scope)

	// Set URL query.
	query := req.URL.Query()
	query.Set("X-Amz-Algorithm", signV4Algorithm)

        for (Iterator<Dependency> it = depMgmt.getDependencies().iterator(); it.hasNext(); ) {
            Dependency dependency = it.next();

            if (!"pom".equals(dependency.getType()) || !"import".equals(dependency.getScope())) {
                continue;
            }

            it.remove();

            String groupId = dependency.getGroupId();
            String artifactId = dependency.getArtifactId();

    protected void mergeDependency_Scope(
            Dependency target, Dependency source, boolean sourceDominant, Map<Object, Object> context) {
        String src = source.getScope();
        if (src != null) {
            if (sourceDominant || target.getScope() == null) {
                target.setScope(src);
                target.setLocation("scope", source.getLocation("scope"));
            }
        }
    }