Эффективное получение нескольких срезов из Objectified XML

Question

Если у меня есть XML, который я использовал lxml для Objectify, как мне получить фрагменты списка эффективно?

Мой сценарий.

# from lxml import etree 
from lxml import objectify 
import argparse 
import os 

parser = argparse.ArgumentParser() 
parser.add_argument("path", type=str, nargs="+") 
parser.add_argument('-e', 
        '--extension', 
        default='', 
        help='File extension to filter by.') 

args = parser.parse_args() 
name_pattern = "*" + args.extension 
my_dir = args.path[0] 

for dir_path, subdir_list, file_list in os.walk(my_dir): 
    for name_pattern in file_list: 
     full_path = os.path.join(dir_path, name_pattern) 


def getsMeet(file_list): 
    for filename in sorted(file_list): 
     filename=my_dir + filename 
     yield filename 

def parseXML(): 
    """ 
    """ 
    for file in getsMeet(file_list): 
     with open(file) as f: 
      xml = f.read() 

      root = objectify.fromstring(xml) 
      print(objectify.dump(root.race.nomination[0])) 
      find = objectify.ObjectPath(".race.nomination") 
      print(find.hasattr(root)) 


parseXML() 

XML-поток от root = meeting> Club> Race> Условие | Выдвижение

Так что печать показать структуру номинации

print(objectify.dump(root.race.nomination[0])) 

(pyxml) [sayth@localhost pyxml]$ python xrace.py data/ -e .xml 
nomination = '' [StringElement] 
    * number = '8' 
    * saddlecloth = '8' 
    * horse = 'Chipanda' 
    * id = '198926' 
    * idnumber = '' 
    * regnumber = '' 
    * blinkers = '0' 
    * trainernumber = '235' 
    * trainersurname = "O'Shea" 
    * trainerfirstname = 'John' 
    * trainertrack = 'Agnes Banks/Hawkesbury' 
    * rsbtrainername = "John O'Shea" 
    * jockeynumber = '84015' 
    * jockeysurname = 'Avdulla' 
    * jockeyfirstname = 'Brenton' 
    * barrier = '5' 
    * weight = '54' 
    * rating = '0' 
    * description = 'B F 2 Sepoy x Lobola (Anabaa(USA))' 
    * colours = 'Royal Blue' 
    * owners = 'Godolphin ' 
    * dob = '2013-10-08T00:00:00' 
    * age = '3' 
    * sex = 'F' 
    * career = '2-0-0-2 $30225.00' 
    * thistrack = '1-0-0-1 $15000.00' 
    * thisdistance = '0-0-0-0' 
    * goodtrack = '0-0-0-0' 
    * heavytrack = '0-0-0-0' 
    * slowtrack = '' 
    * deadtrack = '' 
    * fasttrack = '0-0-0-0' 
    * firstup = '2-0-0-2 $30225.00' 
    * secondup = '0-0-0-0' 
    * mindistancewin = '0' 
    * maxdistancewin = '0' 
    * finished = '1' 
    * weightvariation = '0' 
    * variedweight = '54' 
    * decimalmargin = '0.00' 
    * penalty = '0' 
    * pricestarting = '$3.50' 
    * sectional200 = '0' 
    * sectional400 = '0' 
    * sectional600 = '0' 
    * sectional800 = '0' 
    * sectional1200 = '0' 
    * bonusindicator = 'E' 
True 

Если я хочу, чтобы вернуть эти элементы, как я должен это сделать?

* number = '8' 
    * saddlecloth = '8' 
    * horse = 'Chipanda' 
    * id = '198926' 
    * barrier = '5' 
    * weight = '54' 
    * rating = '0' 
    * description = 'B F 2 Sepoy x Lobola (Anabaa(USA))' 
    * colours = 'Royal Blue' 
    * owners = 'Godolphin ' 
    * dob = '2013-10-08T00:00:00' 
    * age = '3' 
    * sex = 'F' 
    * career = '2-0-0-2 $30225.00' 
    * thistrack = '1-0-0-1 $15000.00' 
    * thisdistance = '0-0-0-0' 
    * goodtrack = '0-0-0-0' 
    * heavytrack = '0-0-0-0' 
    * finished = '1' 
    * weightvariation = '0' 
    * variedweight = '54' 
    * decimalmargin = '0.00' 
    * penalty = '0' 
    * pricestarting = '$3.50' 

Пример XML

<meeting id="42977" barriertrial="0" venue="Rosehill Gardens" date="2016-05-21T00:00:00" gearchanges="-1" stewardsreport="-1" gearlist="-1" racebook="0" postracestewards="0" meetingtype="TAB" rail="Timing - Electronic : Rail - +6m" weather="Fine  " trackcondition="Good 3 " nomsdeadline="2016-05-16T11:00:00" weightsdeadline="2016-05-17T16:00:00" acceptdeadline="2016-05-18T09:00:00" jockeydeadline="2016-05-18T12:00:00"> 
    <club abbrevname="Australian Turf Club" code="56398" associationclass="1" website="http://" /> 
    <race id="215411" number="1" nomnumber="9" division="0" name="LES CARLYON AC PLATE" mediumname="2Y-SWP" shortname="2Y-SWP" stage="Results" distance="1200" minweight="0" raisedweight="0" class="~   " age="2   " grade="0" weightcondition="SWP  " trophy="0" owner="0" trainer="0" jockey="0" strapper="0" totalprize="85000" first="48750" second="16750" third="8350" fourth="4150" fifth="2000" time="2016-05-21T11:25:00" bonustype="BOB7  " nomsfee="0" acceptfee="0" trackcondition="Good 3 " timingmethod="Electronic" fastesttime="1-10.22 " sectionaltime="600/34.78 " formavailable="0" racebookprize="Of $85000. First $48750, second $16750, third $8350, fourth $4150, fifth $2000, sixth $1000, seventh $1000, eighth $1000, ninth $1000, tenth $1000"> 
    <condition line="1">Of $85000. First $48750, second $16750, third $8350, fourth $4150, fifth $2000, sixth $1000, seventh $1000, eighth $1000, ninth $1000, tenth $1000</condition> 
    <condition line="2">Starter Subsidy: $200 for non-prize earning runners.</condition> 
    <condition line="3">No class restriction, Set Weights plus Penalties, For Two-Years-Old, No sex restriction</condition> 
    <condition line="4">BOBS Bonus available: $20,000</condition> 
    <condition line="5">Apprentices can claim. Field Limit: 16 + 4 EM</condition> 
    <nomination number="8" saddlecloth="8" horse="Chipanda" id="198926" idnumber="" regnumber="" blinkers="0" trainernumber="235" trainersurname="O'Shea" trainerfirstname="John" trainertrack="Agnes Banks/Hawkesbury" rsbtrainername="John O'Shea" jockeynumber="84015" jockeysurname="Avdulla" jockeyfirstname="Brenton" barrier="5" weight="54" rating="0" description="B F 2 Sepoy x Lobola (Anabaa(USA))" colours="Royal Blue" owners="Godolphin " dob="2013-10-08T00:00:00" age="3" sex="F" career="2-0-0-2 $30225.00" thistrack="1-0-0-1 $15000.00" thisdistance="0-0-0-0" goodtrack="0-0-0-0" heavytrack="0-0-0-0" slowtrack="" deadtrack="" fasttrack="0-0-0-0" firstup="2-0-0-2 $30225.00" secondup="0-0-0-0" mindistancewin="0" maxdistancewin="0" finished="1" weightvariation="0" variedweight="54" decimalmargin="0.00" penalty="0" pricestarting="$3.50" sectional200="0" sectional400="0" sectional600="0" sectional800="0" sectional1200="0" bonusindicator="E" /> 
    <nomination number="1" saddlecloth="1" horse="Legerity" id="200769" idnumber="" regnumber="" blinkers="0" trainernumber="77974" trainersurname="Hawkes" trainerfirstname="Michael" trainertrack="Rosehill" rsbtrainername="Michael, Wayne &amp; John Hawkes" jockeynumber="2687" jockeysurname="Reith" jockeyfirstname="Christian" barrier="1" weight="57.5" rating="0" description="B C 2 Snitzel x Simply Spiteful(USA) (Speightstown(USA))" colours="Purple, Gold Checks, Quartered Cap" owners="Highgrove Stud Syndicate (Mgr: R T Gilbert)" dob="2013-08-30T00:00:00" age="3" sex="C" career="4-1-1-1 $85075.00" thistrack="1-1-0-0 $68750.00" thisdistance="0-0-0-0" goodtrack="3-1-0-1 $77150.00" heavytrack="0-0-0-0" slowtrack="" deadtrack="" fasttrack="0-0-0-0" firstup="2-0-1-1 $15125.00" secondup="2-1-0-0 $69950.00" mindistancewin="0" maxdistancewin="0" finished="2" weightvariation="0" variedweight="57.5" decimalmargin="0.50" penalty="0" pricestarting="$2.50F" sectional200="0" sectional400="0" sectional600="0" sectional800="0" sectional1200="0" bonusindicator="E" /> 
</race> 
</meeting> 

я могу получить все значения с этим defaultdict Однако, кажется, я не использую объективизации должным образом.

d = defaultdict(list) 
    # nomItems = ['id', 'horse'] 
    for sample in root.xpath('//race/nomination'): 
     for attr_name, attr_value in sample.items(): 
      d[attr_name].append(attr_value) 

pprint(dict(d)) 

Answer 1

Вы можете получить несколько атрибутов в одном выражении, но вам нужно будет добавить их в порядке их появления, если вы хотите знать, что принадлежит к которому:

.xpath(('//race/nomination/@*[name() = "number" or name() = "saddlecloth" or name() = "horse"]' 

Другой вариант тянуть от ATTRIB Словаря, используя operator.itemgetter:

from operator import itemgetter 

atts = ("number", "id", "horse", "saddlecloth", "barrier", "weight", "rating", "description", "colours", 
    "owners", "dob", "age", "sex", "career", "thistrack", "thisdistance", "goodtrack", "heavytrack", 
    "finished", "weightvariation", "variedweight", "decimalmargin", "penalty", "pricestarting") 

for sample in root.xpath('//race/nomination'): 
     print(dict(zip(atts, (itemgetter(*atts)(sample.attrib) 

Для примера XML выведет:

{'thistrack': '1-0-0-1 $15000.00', 'rating': '0', 'weight': '54', 'number': '8', 'sex': 'F', 'id': '198926', 'penalty': '0', 'horse': 'Chipanda', 'pricestarting': '$3.50', 'colours': 'Royal Blue', 'saddlecloth': '8', 'description': 'B F 2 Sepoy x Lobola (Anabaa(USA))', 'barrier': '5', 'weightvariation': '0', 'finished': '1', 'variedweight': '54', 'goodtrack': '0-0-0-0', 'owners': 'Godolphin ', 'decimalmargin': '0.00', 'dob': '2013-10-08T00:00:00', 'thisdistance': '0-0-0-0', 'age': '3', 'heavytrack': '0-0-0-0', 'career': '2-0-0-2 $30225.00'} 
{'thistrack': '1-1-0-0 $68750.00', 'rating': '0', 'weight': '57.5', 'number': '1', 'sex': 'C', 'id': '200769', 'penalty': '0', 'horse': 'Legerity', 'pricestarting': '$2.50F', 'colours': 'Purple, Gold Checks, Quartered Cap', 'saddlecloth': '1', 'description': 'B C 2 Snitzel x Simply Spiteful(USA) (Speightstown(USA))', 'barrier': '1', 'weightvariation': '0', 'finished': '2', 'variedweight': '57.5', 'goodtrack': '3-1-0-1 $77150.00', 'owners': 'Highgrove Stud Syndicate (Mgr: R T Gilbert)', 'decimalmargin': '0.50', 'dob': '2013-08-30T00:00:00', 'thisdistance': '0-0-0-0', 'age': '3', 'heavytrack': '0-0-0-0', 'career': '4-1-1-1 $85075.00'} 

Или, если вы хотите сгруппировать в defauldict:

from collections import defaultdict 
from operator import itemgetter 

d = defaultdict(list) 



for sample in root.xpath('//race/nomination'): 
     for k,v in zip(atts, itemgetter(*atts)(sample.attrib)): 
      d[k].append(v) 

print(d) 

Который даст вам:

defaultdict(<type 'list'>, {'thistrack': ['1-0-0-1 $15000.00', '1-1-0-0 $68750.00'], 'rating': ['0', '0'], 'weight': ['54', '57.5'], 'number': ['8', '1'], 'sex': ['F', 'C'], 'id': ['198926', '200769'], 'penalty': ['0', '0'], 'horse': ['Chipanda', 'Legerity'], 'pricestarting': ['$3.50', '$2.50F'], 'colours': ['Royal Blue', 'Purple, Gold Checks, Quartered Cap'], 'saddlecloth': ['8', '1'], 'description': ['B F 2 Sepoy x Lobola (Anabaa(USA))', 'B C 2 Snitzel x Simply Spiteful(USA) (Speightstown(USA))'], 'barrier': ['5', '1'], 'weightvariation': ['0', '0'], 'finished': ['1', '2'], 'variedweight': ['54', '57.5'], 'goodtrack': ['0-0-0-0', '3-1-0-1 $77150.00'], 'owners': ['Godolphin ', 'Highgrove Stud Syndicate (Mgr: R T Gilbert)'], 'decimalmargin': ['0.00', '0.50'], 'dob': ['2013-10-08T00:00:00', '2013-08-30T00:00:00'], 'thisdistance': ['0-0-0-0', '0-0-0-0'], 'age': ['3', '3'], 'heavytrack': ['0-0-0-0', '0-0-0-0'], 'career': ['2-0-0-2 $30225.00', '4-1-1-1 $85075.00']}) 

Или:

d = defaultdict(list) 

for sample in root.xpath('//race/nomination'): 
    dct = sample.attrib 
    for k in atts: 
     d[k].append(dct[k]) 

print(d) 

Для любого отсутствует ключей/атрибутов, чтобы установить значение по умолчанию None:

for sample in root.xpath('//race/nomination'): 
     print(dict(zip(atts, map(sample.attrib.get, atts)))) 

Dict поиски являются O (1), так что я не думаю, что вы собираетесь получить гораздо более эффективный способ, чтобы вытащить атрибуты, которые вы хотите.