Capture (remove) all double-quotes after colon - regex

Question

I'm trying to clean up a string. An example string:
{
"NodeID": "${NodeID}",
"EventID": "${EventID}"
}
I want to capture all double quotes which occur after the colon, so that the end string will be:
{
"NodeID": ${NodeID},
"EventID": ${EventID}
}
I know that it's JSON, and that technically it is a string in those positions, but they're macros that will be interpreted by a system which generates the actual JSON string and replaces the macros with data, so in my use case this text isn't JSON yet. I can deal with the text line-by-line to make it easier.
I'll be using the regex pattern in both PowerShell and Python.
The closest I've gotten so far have been: (?<=[^*:])("), and (?<=:)(.*)(?<!,)
This is working, but seems incredibly kludgy and inelegant:
$String = '{
"NodeID": "${NodeID}",
"EventID": "${EventID}"
}'
# The Regex to match the text after the colon
[regex]$Regex = '(?<=:)(.*)'
# Splitting each line of the string into an ArrayList element
[System.Collections.ArrayList]$StringArray = $String.Split([string[]][Environment]::NewLine, [StringSplitOptions]::None)
# Declaring an output string
$OutPutString = ''
# Loop through the ArrayList
$i = 1
foreach ($Row in $StringArray) {
# Split each element string at the RegEx match
$RowArray = $Row -split $Regex
[String]$RowString1 = $RowArray[0]
[String]$RowString2 = $RowArray[1]
# Reassemble the element string after replacing the double quotes in the 2nd half
$FullRowString = $RowString1 + $RowString2.Replace('"','')
# If this is the first line in the string, don't add a new line charact in front
if ($i -gt 1) {
$NewLine = "`n"
}
# Reassemble the string
$OutPutString += $NewLine + $FullRowString
$i++
}
$OutPutString
Any better ideas?

Answer 1

👉️ For the regex to be functional as expected, the regex-engine indicated by scripting/programming language is important to know.
Please always add this information as tags besides regex.
Here: powershell, python
Regex to match a JSON text-field and capture the raw-value
Tested on Python, see regex101 demo:
(?<=:\s\s)\"([^\"]*)\"
💡️ Components
To explain the composition of the regex and its working in steps:
(?<=:\s\s): positive look behind ?<=: for 2 white-spaces \s\s
to neglect the field-name also enclosed in double-quotes
\" and \": matching double-quotes before and after the capture group
the unwanted enclosing of the field-value
([^\"]*): capture-group denoted by parentheses surround any non-double-quote character [^\"]*
the wanted raw field-value (string) without enclosing double-quotes
ℹ️ Note:
The character-group [^\"] matches any non (^) double-quote \".
It will start matching at the leading double-quote and stop matching as soon as a double-quote is detected. So the final \" in the regex is optional: It is not required for matching/capturing, but will ensure that each matched field-value is correctly enclosed by double-quotes.
Result
Matching following input lines:
{
"NodeID": "${NodeID}",
"EventID": "${EventID}"
}
Will give the desired raw field-values in group 1 for each match:
e.g.
${NodeID} for the first match
${EventID} for the second match
📚️ Working with JSON in PowerShell
For your context assumed as parsing JSON following related links may be useful:
Microsoft Scripting Blog: Working with JSON data in PowerShell
Related Question: PowerShell parsing JSON
PowerShell Explained: Powershell: The many ways to use regex