HI Gavin -
These files are starting points for mapping and indexing XML responses from the Twitter API. The default mapping list is intended to capture as many fields as possible, but refrains from using the long-form metadata class names (https://docs.funnelback.com/metadata_class.html).
You could also use a setting like https://docs.funnelback.com/indexing_additional_metamap_source_collection_cfg.html to define your own reusable mappings. In practice, all fields coming back from the Twitter API are available for use, provided you've got a corresponding entry in your collection's xml.cfg.
$SEARCH_HOME/share/custom_collection_templates/xml.cfg.twitter looks like:
PADRE XML Mapping Version: 2
docurl,/FacebookXmlRecord/url
docfiletype,/db_record/funnelback_filetype
a,1,,/FacebookXmlRecord/postFrom/name
a,1,,/FacebookXmlRecord/eventOwner/name
a,1,,/FacebookXmlRecord/page/name
c,1,,/FacebookXmlRecord/postMessage
b,3,,/dummy/path/b #Required for compatibility with other social media collections.
c,1,,/FacebookXmlRecord/eventDescription
c,1,,/FacebookXmlRecord/page/description
d,1,,/FacebookXmlRecord/postCreatedTime
d,1,,/FacebookXmlRecord/eventStartTime
e,3,,/dummy/path/e #Required for compatibility with other social media collections.
f,3,,//dummy/path/f #Required for compatibility with other social media collections.
j,1,,/FacebookXmlRecord/postId
j,1,,/FacebookXmlRecord/eventId
j,1,,/FacebookXmlRecord/page/id
t,1,,/FacebookXmlRecord/eventName
x,3,,//dummy/path/x #Required for compatibility with other social media collections.
A,1,,/FacebookXmlRecord/postFrom/id
A,1,,/FacebookXmlRecord/eventOwner/id
B,1,,/FacebookXmlRecord/page/about
C,1,,/FacebookXmlRecord/page/category
C,1,,//commentMessage
D,1,,/FacebookXmlRecord/eventEndTime
E,1,,/FacebookXmlRecord/postLink
F,1,,/FacebookXmlRecord/page/founded
G,1,,/FacebookXmlRecord/postLinkCaption
H,1,,/FacebookXmlRecord/postLinkDescription
I,1,,/FacebookXmlRecord/postPictureURL
J,1,,/FacebookXmlRecord/postIconURL
L,1,,/FacebookXmlRecord/eventLocation
M,1,,/FacebookXmlRecord/page/mission
N,1,,/FacebookXmlRecord/page/phone
O,1,,/FacebookXmlRecord/eventVenue/state
O,1,,/FacebookXmlRecord/page/location/state
O,1,,/FacebookXmlRecord/postLocation/state
P,1,,/FacebookXmlRecord/page/products
P,1,,/FacebookXmlRecord/eventPrivacy
Q,1,,/FacebookXmlRecord/eventVenue/zip
Q,1,,/FacebookXmlRecord/page/location/zip
Q,1,,/FacebookXmlRecord/postLocation/zip
S,1,,/FacebookXmlRecord/eventVenue/street
S,1,,/FacebookXmlRecord/page/location/street
S,1,,/FacebookXmlRecord/postLocation/street
T,1,,/FacebookXmlRecord/type
V,1,,/FacebookXmlRecord/eventVenue/country
V,1,,/FacebookXmlRecord/page/location/country
V,1,,/FacebookXmlRecord/postLocation/country
W,1,,/FacebookXmlRecord/eventVenue/city
W,1,,/FacebookXmlRecord/page/location/city
W,1,,/FacebookXmlRecord/postLocation/city