XML parsing with namespaces using XML package in R - r

Question

I am trying to parse a xml file using XML package of R. Sample XML content is as follows:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
<soapenv:Header>
<messageContext xmlns="http://www.deltavista.com/dspone/ordercheck-if/V001">
<credentials>
<user>foobar</user>
<password>barbaz</password>
</credentials>
</messageContext>
</soapenv:Header>
<soapenv:Body>
<ns1:orderCheckResponse xmlns:ns1="http://www.deltavista.com/dspone/ordercheck-if/V001">
<ns1:returnCode>1</ns1:returnCode>
<ns1:product>
<ns1:name>Consumer</ns1:name>
<ns1:country>POL</ns1:country>
<ns1:language>POL</ns1:language>
</ns1:product>
<ns1:archiveID>420</ns1:archiveID>
<ns1:reportCreationTime>201911151220</ns1:reportCreationTime>
<ns1:foundAddress>
<ns1:legalForm>PERSON</ns1:legalForm>
<ns1:address>
<ns1:name>John</ns1:name>
<ns1:firstName>Dow</ns1:firstName>
<ns1:gender>MALE</ns1:gender>
<ns1:dateOfBirth>19960410</ns1:dateOfBirth>
<ns1:location>
<ns1:street>nowhere</ns1:street>
<ns1:house>48</ns1:house>
<ns1:city>farfarland</ns1:city>
<ns1:zip>00-500</ns1:zip>
<ns1:country>POL</ns1:country>
</ns1:location>
</ns1:address>
</ns1:foundAddress>
<ns1:myDecision>
<ns1:decision>YELLOW</ns1:decision>
</ns1:myDecision>
<ns1:personBasicData>
<ns1:knownSince>20181201</ns1:knownSince>
<ns1:contact>
<ns1:item>EMAIL</ns1:item>
<ns1:value>foo#gmail.com</ns1:value>
</ns1:contact>
<ns1:contact>
<ns1:item>PHONE</ns1:item>
<ns1:value>123456789</ns1:value>
</ns1:contact>
</ns1:personBasicData>
<ns1:decisionMatrix>
<ns1:identificationDecision>
<ns1:personStatus xsi:type="ns1:DecisionMatrixItemPersonStatus" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>ADULT</ns1:value>
</ns1:personStatus>
<ns1:identificationType xsi:type="ns1:DecisionMatrixItemIdentificationType" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>IDENTITY_IN_CITY</ns1:value>
</ns1:identificationType>
<ns1:similarHit xsi:type="ns1:DecisionMatrixItemInt" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>0</ns1:value>
</ns1:similarHit>
<ns1:houseType xsi:type="ns1:DecisionMatrixItemString" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>SHARED_USAGE</ns1:value>
</ns1:houseType>
<ns1:nameHint xsi:type="ns1:DecisionMatrixItemNameHint" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>CONFIRMED</ns1:value>
</ns1:nameHint>
<ns1:locationIdentificationType xsi:type="ns1:DecisionMatrixItemLocationIdentificationType" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>HOUSE_CONFIRMED</ns1:value>
</ns1:locationIdentificationType>
</ns1:identificationDecision>
<ns1:solvencyDecision>
<ns1:paymentExperience xsi:type="ns1:DecisionMatrixItemPHS" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>NOPROBLEM</ns1:value>
</ns1:paymentExperience>
<ns1:externalSourcesProcessingStatus xsi:type="ns1:DecisionMatrixItemExternalProcessingStatus" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>OK</ns1:value>
</ns1:externalSourcesProcessingStatus>
</ns1:solvencyDecision>
<ns1:clientExtensionsDecision>
<ns1:applicationFilter xsi:type="ns1:DecisionMatrixItemStringWithOverride" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>GREEN</ns1:partialDecision>
<ns1:value>0</ns1:value>
</ns1:applicationFilter>
<ns1:myScore xsi:type="ns1:DecisionMatrixItemInt" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:partialDecision>YELLOW</ns1:partialDecision>
<ns1:value>401</ns1:value>
</ns1:myScore>
</ns1:clientExtensionsDecision>
</ns1:decisionMatrix>
<ns1:paymentHistory>
<ns1:currency>PLN</ns1:currency>
<ns1:count>0</ns1:count>
<ns1:dateOfLastEntry>20191111</ns1:dateOfLastEntry>
<ns1:amountTotal>0.0</ns1:amountTotal>
<ns1:amountTotalOpen>0.0</ns1:amountTotalOpen>
<ns1:creditStatusMax>0</ns1:creditStatusMax>
<ns1:masterRiskStatus>Brak danych o negatywnej historii</ns1:masterRiskStatus>
</ns1:paymentHistory>
<ns1:normalization>
<ns1:searchedAddress xsi:type="ns1:SearchedAddressN" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns1:name>John</ns1:name>
<ns1:firstName>Dow</ns1:firstName>
<ns1:gender>MALE</ns1:gender>
<ns1:dateOfBirth>19960410</ns1:dateOfBirth>
<ns1:location>
<ns1:street>nowhere</ns1:street>
<ns1:house>39</ns1:house>
<ns1:houseExtension/>
<ns1:city>farfarland</ns1:city>
<ns1:zip>00-500</ns1:zip>
<ns1:country>POL</ns1:country>
</ns1:location>
<ns1:addressID>123</ns1:addressID>
<ns1:unitID>123</ns1:unitID>
<ns1:liableID>1231</ns1:liableID>
<ns1:houseID>1232</ns1:houseID>
<ns1:streetID>1233</ns1:streetID>
<ns1:cityID>1234</ns1:cityID>
</ns1:searchedAddress>
<ns1:foundAddress>
<ns1:addressID>1235</ns1:addressID>
<ns1:unitID>1236</ns1:unitID>
<ns1:liableID>1237</ns1:liableID>
<ns1:houseID>1238</ns1:houseID>
<ns1:streetID>1239</ns1:streetID>
<ns1:cityID>1230</ns1:cityID>
</ns1:foundAddress>
</ns1:normalization>
<ns1:clientExtensions>
<ns1:additionalData>
<ns1:name>pesel_verification_status</ns1:name>
<ns1:value>1</ns1:value>
</ns1:additionalData>
<ns1:additionalData>
<ns1:name>pesel_verification_execution_code</ns1:name>
<ns1:value>200</ns1:value>
</ns1:additionalData>
<ns1:additionalData>
<ns1:name>pesel_verification_codes</ns1:name>
<ns1:value>12010; 12013</ns1:value>
</ns1:additionalData>
</ns1:clientExtensions>
<ns1:executionStrategy/>
</ns1:orderCheckResponse>
</soapenv:Body>
</soapenv:Envelope>
Here is the code I am using to read and parse this XML content; str henceforth:
library(XML)
foobar <- xmlInternalTreeParse(str, encoding = 'KOI8-R', useInternalNodes = F)
xmlSApply(foobar$doc$children$Envelope, function(x) xmlSApply(x, names))
xmlSApply(foobar$doc$children$Envelope, function(x) xmlSApply(x, function(x1) xmlSApply(x1, names)))
Here I am able to parse the XML content and tried iterating over nodes to at least print the names. However I couldn't extract the values inside, even though I read many SO questions and tried countless combinations using xPathApply() etc. (reference)
Any hint on what I might be doing wrong here.

Answer 1

Consider a straightforward descendant XPath search with //* that acknowledges namespaces to retrieve all element names and values. However, since your XPath does not reference any namespace prefixes, for this specific search it is redundant in the xpathSApply calls:
doc <- xmlParse(str, asText=TRUE)
nmsp <- c(soapenv = "http://schemas.xmlsoap.org/soap/envelope/",
doc = "http://www.deltavista.com/dspone/ordercheck-if/V001",
ns1 = "http://www.deltavista.com/dspone/ordercheck-if/V001")
# NAMED CHARACTER VECTOR OF ALL 117 ELEMENT NAMES AND VALUES
elem_vals <- setNames(xpathSApply(doc, path="//*", namespaces = nmsp, xmlValue) ,
xpathSApply(doc, path="//*", namespaces = nmsp, xmlName))
Output
Names (first 20 items)
head(names(elem_vals), 20)
# [1] "Envelope" "Header" "messageContext" "credentials" "user"
# [6] "password" "Body" "orderCheckResponse" "returnCode" "product"
# [11] "name" "country" "language" "archiveID" "reportCreationTime"
# [16] "foundAddress" "legalForm" "address" "name" "firstName"
Values (last 20 items)
tail(elem_vals, 20)
# streetID cityID
# "1233" "1234"
# foundAddress addressID
# "123512361237123812391230" "1235"
# unitID liableID
# "1236" "1237"
# houseID streetID
# "1238" "1239"
# cityID clientExtensions
# "1230" "pesel_verification_status1pesel_verification_execution_code200pesel_verification_codes12010; 12013"
# additionalData name
# "pesel_verification_status1" "pesel_verification_status"
# value additionalData
# "1" "pesel_verification_execution_code200"
# name value
# "pesel_verification_execution_code" "200"
# additionalData name
# "pesel_verification_codes12010; 12013" "pesel_verification_codes"
# value executionStrategy
# "12010; 12013" ""