CODEWITHSUNDEEP
xmlpowershell
symcbean
symcbean

Reputation: 48357

Struggling with Powershell XML to CSV

I am trying to convert an XML file to CSV. While the question here was useful, I was unable to apply the suggestions to my case - presumably because my entities are multi-valued. My Xml looks something like:

<?xml version="1.0" encoding="UTF-8">
<ReportOutput Version="1">
  <ReportFilters>
    <Filter Name="Report Name" Value="My report"/>
    <Filter Name="Path" Value="/">
    <Filter Name="attr1" Value="*">
    ...
  </ReportFilters>
  <ReportHeader>
    <columnHeader>attr1</columnheader>
    <columnHeader>attr2</columnheader>
    <columnHeader>attr3</columnheader>
    ...
  </ReportHeader>
  <ReportRecord>
    <item>1</item>
    <item>first</item>
    <item>A</item>
    ...
  </ReportRecord>
  <ReportRecord>
    <item>2</item
    <item>second</item>
    <item>B</item>
    ...
  </ReportRecord>
  ...
</ReportOutput>
(where '...' represents one or recurrences of the previous node pattern)

The XML is merely a thin wrapper aroun d something which is intrinsically a tabular dataset - the ReportHeader and ReportRecord nodes all contain the same number of childnodes.

I want the ReportHeader.columnHeaders and ReportRecord.Items in my CSV file:

attr1, attr2, attr3 ...
1, first, A ...
2, second, B ...

I can remove the ReportFilters easily enough:

[xml]$xml = Get-Content data.xml

$filter=$xml.ReportOutput.ReportFilters
$filter.ParentNode.RemoveChild($filter)

but iterating through the data is bit more tricky.

$xml.ReportOutput.ChildNodes | Export-Csv "C:\Temp\report.csv" -NoTypeInformation -Delimiter:"," -Encoding:UTF8

The first record in the CSV file is the single attribute '"columnHeader"', second record is '"System.Object[]"' thereafter, lots of blank lines.

 {
    $xml.ReportOutput.ReportHeader | ConvertTo-Csv -NoTypeInformation -Delimiter:","
    foreach ($r in $xml.ReportRecord) {
    $r | ConvertTo-Csv -NoTypeInformation -Delimiter:","
    }
} | Set-Content -Path "C:\Temp\report.csv" -Encoding:UTF8

wrote part of the source code to the output stream.

 $xml.ReportOutput.ReportHeader | ConvertTo-Csv -NoTypeInformation -Delimiter:"," | Set-Content -Path "C:\Temp\report.csv" -Encoding:UTF8
 foreach ($r in $xml.ReportOutput.ReportRecord) {
    $r | ConvertTo-Csv -NoTypeInformation -Delimiter:"," | Add-Content -Path "C:\Temp\report.csv" -Encoding:UTF8
 }

just wrote lots of gibberish.

 $xml.ReportOutput.ReportHeader.ChildNodes | ConvertTo-Csv -NoTypeInformation -Delimiter:"," | Set-Content -Path "C:\Temp\report.csv" -Encoding:UTF8
 foreach ($r in $xml.ReportOutput.ReportRecord) {
    $r.ChildNodes | ConvertTo-Csv -NoTypeInformation -Delimiter:"," | Add-Content -Path "C:\Temp\report.csv" -Encoding:UTF8
 }

had the data - but as one attribute per record

Upvotes: 0

Views: 881

Answers (2)

symcbean
symcbean

Reputation: 48357

Greg's (excellent) solution uses string splicing to create a prototype CSV file (in $csv) then converts it back to a powershell collection and then to CSV as a cleaning stage. The string splicing method is not very sophisticated and things get messy if the input data contains things seen as CSV meta-data (i.e. commas). Hence I found it safer to use a tab char:

$csv = @(($xml = [xml](Get-Content C:\path\input.xml)).SelectNodes('//columnHeader').'#text' -join "`t")
$csv += $xml.SelectNodes('//ReportRecord').ForEach{$_.item -join "`t"}
$csv | ConvertFrom-Csv -Delimiter "`t" | Export-Csv C:\path\output.csv

This is not completely robust, but good enough for me.

Upvotes: 0

user9952217
user9952217

Reputation:

I sincerely believe that your XML document is valid and all of the closing tags in it are correct (as it a hint). So...

# create header of the future CSV (attr1,attr2,attr3...)
$csv = @(($xml = [xml](Get-Content C:\path\input.xml)).SelectNodes('//columnHeader').'#text' -join ',')
# append lines to the future CSV
$csv += $xml.SelectNodes('//ReportRecord').ForEach{$_.item -join ','}
# at present moment $csv is the array
# attr1,attr2,attr3...
# 1,first,A...
# 2,second,B...
# time to write this data as CSV on disk
$csv | ConvertFrom-Csv | Export-Csv C:\path\output.csv

Hope this helps.

Upvotes: 1

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