R XML - combining parent and child nodes into data frame

Question

I have xml like this:

Answer 1

Consider parsing meeting data by node index and expand it to the number of its child race elements, then column bind with race data:

doc <- xmlParse("/path/to/Source.xml")

# NUMBER OF MEETING NODES
mtg_num <- length(xpathSApply(doc, "//meeting"))

# DATAFRAME LIST OF EXPANDED MEETING ATTRS
meeting_list <- lapply(seq(mtg_num), function(i) {
  races_num <- length(xpathSApply(doc, sprintf("//meeting[%s]/race", i)))

  data.frame(
    meeting_id = rep(xpathSApply(doc, sprintf("//meeting[%s]/@id", i)), races_num),
    meeting_name = rep(xpathSApply(doc, sprintf("//meeting[%s]/@name", i)), races_num)
  )
})

# COLUMN BIND MEETING NODES, RACE NODES, AND RACE ATTRS
final_df <- cbind(do.call(rbind, meeting_list),
                  xmlToDataFrame(nodes = getNodeSet(doc, "//meeting/race")),
                  XML:::xmlAttrsToDataFrame(getNodeSet(doc, "//meeting/race")))

Output

head(final_df)

#   meeting_id      meeting_name  time       date ampm                                                       title type distance    group tipsAllowed predictorAllowed
# 1        195 Punchestown (IRE) 12:25 2018-01-13   pm                      Adare Manor Opportunity Handicap Chase    C     2m4f Handicap           1                1
# 2        195 Punchestown (IRE)  1:00 2018-01-13   pm         Total Event Rental (Kildare) Novice Chase (Grade 3)    C     2m4f  Grade 3           1                1
# 3        195 Punchestown (IRE)  1:35 2018-01-13   pm Connolly's RED MILLS Amateur National (Q.R.) Handicap Chase    C     3m1f Handicap           1                1
# 4        195 Punchestown (IRE)  2:10 2018-01-13   pm                Sky Bet Moscow Flyer Novice Hurdle (Grade 2)    H       2m  Grade 2           1                1
# 5        195 Punchestown (IRE)  2:45 2018-01-13   pm                              Sportinglife.com Maiden Hurdle    H       2m                    1                1
# 6        195 Punchestown (IRE)  3:20 2018-01-13   pm                       Leinster Leader Mares Handicap Hurdle    H  2m4f40y Handicap           1                1

#  bettingLink declaredRunners liveCommentary liveTab       raceDescription tvText betOffers     id perform_race_id perform_race_id_atr details_available race_status_code
# 1           1              10              1       1        Handicap Chase   ATR        692415                                                     1                R
# 2           1               7              1       1  Novice Chase Grade 3   ATR        692416                                                     1                R
# 3           1              12              1       1        Handicap Chase   ATR        692417                                                     1                R
# 4           1               7              1       1 Novice Hurdle Grade 2   ATR        692418                                                     1                R
# 5           1              17              1       1         Maiden Hurdle   ATR        692419                                                     1                R
# 6           1               8              1       1       Handicap Hurdle   ATR        692420                                                     1                R