Configuration 

URI of the XML file to read. This may be any of the following syntaxes:

• absolute file path: /var/foo/web/fileadmin/import/bar.xml (within the TYPO3 root path or TYPO3_CONF_VARS[BE][lockRootPath])
• file path relative to the TYPO3 root: fileadmin/import/foo.xml
• file path using EXT:: EXT:foo/Resources/Private/Data/bar.xml
• fully qualified URL, e.g. http://www.example.com/foo.xml
• FAL reference with storage ID and file identifier: FAL:2:/foo.xml
• custom syntax: MYKEY:whatever_you_want, see Connector Services

Key-value pairs of options that can be passed to the request. Any of the request options supported by Guzzle HTTP may be used.

Passing a "page" information in the body and setting an accepted mime type in the headers.

'requestOptions' => [
   'body' => '{"page": 1}',
   'headers' => [
      'Accept' => 'application/xml',
   ],
],

Key-value pairs of headers that should be sent along with the request.

Example headers for setting an alternate user agent and defining what reponse format to accept.

'headers' => [
   'User-Agent' => 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:75.0) Gecko/20100101 Firefox/75.0',
   'Accept' => 'application/xml',
]

Encoding of the data found in the file. This value must match any of the encoding values recognized by the PHP libray "mbstring". See https://www.php.net/manual/en/mbstring.supported-encodings.php

It is not necessary to define this parameter if the XML source contains an encoding in its declaration. It will automatically be retrieved. However, if this parameter is defined, it supersedes the encoding from the XML declaration.