src/Stream/Stream.php
public final function getMetadata($key = null)
   {
       return isset($key)
            ? (array_key_exists($key, $this->meta) ? $this->meta[$key] : null)
            : $this->meta;
   }
public final function getMetadata($key = null)
   {
       return isset($key)
            ? (array_key_exists($key, $this->meta) ? $this->meta[$key] : null)
            : $this->meta;
   }
public final function getMetadata ( $ key = null ) { return isset ( $ key ) ? ( array_key_exists ( $ key , $ this -> meta ) ? $ this -> meta [ $ key ] : null ) : $ this -> meta ; }
Get stream metadata

@param string $key metadata key
@return array|mixed|null meta or value for key or null
Get stream metadata