XML attributes in XmlResponseFormatter

[arturf]

At current implementation XmlResponseFormatter allows to build xml from array/objects but there is no ability to add some attributes for nodes.
In my project I'm using an inherited class with some additions.

/**
     * @inheritdoc
     */
    protected function buildXml($element, $data)
    {
    if (isset($data['attributes'])) {
            $this->attributes = $data['attributes'];
            unset ($data['attributes']);
        }
        parent::buildXml($element, $data);

        $this->buildAttributes($element);
    }

    /**
     * @param DOMElement $element
     */
    protected function buildAttributes($element)
    {
        if (is_null($this->attributes)) {
            return;
        }

        foreach ($this->attributes as $name => $value) {
            $element->setAttribute($name, $value);
        }

        $this->attributes = null;
    }

And some part of code, that adds ability to add attributes for rootTag

I think that this can be good in core. If ok, I will send a PR.

[qiangxue]

We do not have plan to support this out-of-box for the following reasons:

• XmlResponseFormatter is a generic class which cannot assume attributes as a special one;
• XmlResponseFormatter is meant to be extended if you have special format requirement like this;
• There is a special requirement for the data format of attributes if you want to save them as tag attributes;
• When tag attribute is supported, it will not be easy to convert back to arrays from XMLs.