ParagonIE\CSPBuilder\CSPBuilder::sendCSPHeader PHP Method

    public function sendCSPHeader(bool $legacy = true) : bool
    {
        if (\headers_sent()) {
            throw new \Exception('Headers already sent!');
        }
        if ($this->needsCompile) {
            $this->compile();
        }
        foreach ($this->getHeaderKeys($legacy) as $key) {
            \header($key . ': ' . $this->compiled);
        }
        return true;
    }