Convert Json with columns and rows to csv using powershell - json

Question

Please help me to convert my below json file to csv.
{
"count": 12,
"name": "Daily Ticket",
"columnNames": [
"User",
"Channel",
"Date",
"# of Closed Incidents",
"Open",
"Response",
"Remark",
"Closed"
],
"rows": [
[
"abc",
"Service Web",
"\u00272020-06-13 00:00:00\u0027",
"1",
"0",
"0",
"0",
"1"
],
[
"xyz",
"Email",
"\u00272020-06-13 00:00:00\u0027",
"21",
"1",
"0",
"10",
"7"
]
]
}
I want column names as header and rows as rows separated with comma in csv.
The expected output is like below:
User,Channel,Date,# of Closed Incidents,Open,Response,Remark,Closed
abc,Service Web,\u00272020-06-13 00:00:00\u0027,1,0,0,0,1
xyz,Email,\u00272020-06-13 00:00:00\u0027,1,0,0,0,1

Answer 1

I'd offer the simplest approach I know:
$jsonText = #'
{"count":12,"name":"Daily Ticket","columnNames":["User","Channel","Date","# of Closed Incidents","Open","Response","Remark","Closed"],"rows":[["abc","Service Web","\u00272020-06-13 00:00:00\u0027","1","0","0","0","1"],["xyz","Email","\u00272020-06-13 00:00:00\u0027","21","1","0","10","7"]]}
'#
$json = $jsonText | ConvertFrom-Json
$jsonCsvLines = [System.Collections.ArrayList]::new()
[void]$jsonCsvLines.Add( $json.columnNames -join ',')
foreach ( $jsonCsvRow in $json.rows ) {
[void]$jsonCsvLines.Add( $jsonCsvRow -join ',')
}
$jsonCsvLines
$jsonCsv = $jsonCsvLines |
ConvertFrom-Csv -Delimiter ',' |
ConvertTo-Csv -Delimiter ',' -NoTypeInformation
$jsonCsvNoQuotes = $jsonCsv -replace [regex]::Escape('"')
Here
the here-string $jsonText is a compressed version of your example;
the $jsonCsvLines is simple collection (no CSV);
the $jsonCsv is a genuine csv where all fields are enclosed in double quotes, while the $jsonCsvNoQuotes is a csv where no field is enclosed in double quotes.

Answer 2

So far as I can tell (and I'm happy to be corrected) the format of the resulting PSCustomObjects from ConvertTo-JSON isn't suitable for direct consumption by ConvertTo-CSV
You need to relate the elements in row array with the column names. Create an array of objects with the correct property names and values. The way I solved this was to use the array index to associate each row array element with a column name:
$JSON = Get-Content 'C:\Temp\sample.json' | ConvertFrom-Json
$Rows =
ForEach($Row in $JSON.Rows )
{
$TmpHash = [Ordered]#{}
For($i = 0; $i -lt $Row.Length; ++$i )
{
$TmpHash.Add( $JSON.columnNames[$i], $Row[$i] )
}
[PSCustomObject]$TmpHash
}
$Rows | ConvertTo-Csv -NoTypeInformation
Obviously change the file name or whatnot.
On my workstation this results are like:
"User","Channel","Date","# of Closed Incidents","Open","Response","Remark","Closed"
"abc","Service Web","'2020-06-13 00:00:00'","1","0","0","0","1"
"xyz","Email","'2020-06-13 00:00:00'","21","1","0","10","7"
There are definitely different code patterns that can be employed here, but the theme should work.
One important difference is you had a unicode character for apostrophe \u0027 in the source JSON in my output that's properly interpreted. Just pointing out because it's one thing that differs from your sample.
I think this is pretty close to what you needed. Let me know if anything. Thanks.

Answer 3

Sorry to keep this going, but I'm intrigued by JosefZ's answer . This is not to override or critique, it's just for conversation's sake.
Considering ConvertFrom-Json returns PSCustomObjects my first answer went directly to using the same as input for ConvertTo-Csv. Even though creating Csv strings is common in the field it didn't occur to me at the time. I also didn't notice your sample output was unquoted, apologies for that.
At any rate here's my interpretation of JosefZ's answer
Note: In any of these samples -join would work just as well. I just
invoking static methods; however I don't know advantages /
disadvantages between -join & [String]::Join().
$JSON = Get-Content 'C:\Temp\sample.json' | ConvertFrom-Json
$Lines = .{
[String]::Join( ',', $JSON.columnNames )
$JSON.rows | ForEach-Object{ [String]::Join( ',', $_ ) }
}
# $Lines is already in unquoted CSV format. If you want to quote it
$Lines | ConvertFrom-Csv | ConvertTo-Csv -NoTypeInformation
If you only need the quoted or unquoted you can drop the $Lines assignment and pipe all the way through.
Quoted:
$JSON = Get-Content 'C:\Temp\sample.json' | ConvertFrom-Json
.{
[String]::Join( ',', $JSON.columnNames )
$JSON.rows | ForEach-Object{ [String]::Join( ',', $_ ) }
} | ConvertFrom-Csv | ConvertTo-Csv -NoTypeInformation
Un-Quoted:
$JSON = Get-Content 'C:\Temp\sample.json' | ConvertFrom-Json
.{
[String]::Join( ',', $JSON.columnNames )
$JSON.rows | ForEach-Object{ [String]::Join( ',', $_ ) }
}
This approach is a more concise as it can be slimmed to only a few lines. Concise doesn't always mean better or more readable, so again this isn't to override any other approach.
Of course, I don't know what you intend to do with the data after it's properly formatted. If you need to write to a file a simple | Out-File... can be added to the end of any of the above.