func InstallPackageFromGCS()

in integration_test/agents/agents.go [1134:1172]
33 lines of code
11 McCabe index (conditional complexity)

func InstallPackageFromGCS(ctx context.Context, logger *log.Logger, vm *gce.VM, gcsPath string) error {
	if gce.IsWindows(vm.ImageSpec) {
		return installWindowsPackageFromGCS(ctx, logger, vm, gcsPath)
	}
	if _, err := gce.RunRemotely(ctx, logger, vm, "mkdir -p /tmp/agentUpload /tmp/agentPlugin"); err != nil {
		return err
	}
	if err := gce.InstallGsutilIfNeeded(ctx, logger, vm); err != nil {
		return err
	}
	if _, err := gce.RunRemotely(ctx, logger, vm, "sudo gsutil cp -r "+gcsPath+"/* /tmp/agentUpload"); err != nil {
		return fmt.Errorf("error copying down agent package from GCS: %v", err)
	}
	// Print the contents of /tmp/agentUpload into the logs.
	if _, err := gce.RunRemotely(ctx, logger, vm, "ls /tmp/agentUpload"); err != nil {
		return err
	}
	if _, err := gce.RunRemotely(ctx, logger, vm, "rm /tmp/agentUpload/*dbgsym* || echo nothing to delete"); err != nil {
		return err
	}
	if _, err := gce.RunRemotely(ctx, logger, vm, "mv /tmp/agentUpload/*.tar.gz /tmp/agentPlugin || echo nothing to move"); err != nil {
		return err
	}
	if IsRPMBased(vm.ImageSpec) {
		if _, err := gce.RunRemotely(ctx, logger, vm, "sudo rpm --upgrade -v --force /tmp/agentUpload/*"); err != nil {
			return fmt.Errorf("error installing agent from .rpm file: %v", err)
		}
		return nil
	}
	// --allow-downgrades is marked as dangerous, but I don't see another way
	// to get the following sequence to work (from TestUpgradeOpsAgent):
	// 1. install stable package from Rapture
	// 2. install just-built package from GCS
	// Nor do I know why apt considers that sequence to be a downgrade.
	if _, err := gce.RunRemotely(ctx, logger, vm, "sudo apt-get install --allow-downgrades --yes --verbose-versions /tmp/agentUpload/*"); err != nil {
		return fmt.Errorf("error installing agent from .deb file: %v", err)
	}
	return nil
}