How use curl with spaces in json - json

Question

When making a POST call with curl I'm having trouble getting the JSON data to be passed correctly. The string is cut off at the first whitespace/blank space.
My call looks like this, I'm executing through a powershell script that has two parameters. Using these parameters I concatenate the JSON that is used for the call.
I input for instance 854e-ae7686fbc75a 365 as parameters
# usage: powershell -file send.ps1 [apitoken] [interval]
param (
[string]$apitoken = "",
[int]$startInterval = "365"
)
$AUTHORIZATION = $apitoken
$STARTDATE = (Get-Date).AddDays(-$startInterval)
$ENDDATE = (Get-Date)
$JSON = '{\"ApiToken\":\"' + $AUTHORIZATION + '\",' +
'\"StartDate\":\"' + $STARTDATE + '\",' +
'\"EndDate\":\"' + $ENDDATE + '\",' +
'\"Type\":\"SalesExport\"' +
'}'
$CURLEXE = '..\bin\curl.exe'
$CurlArgument = '-X', 'POST',
'-m', 7200,
'-H', '"Content-Type:application/json"',
'-d', $JSON,
'https://my.server/export/sales'
& $CURLEXE #CurlArgument
The STARTDATE would then be the current date minus 365 days. ENDDATE would be the current date.
The problem is as soon as there is a blank space (or possibly any whitespace) in the JSON variable curl thinks that the JSON has ended and says that the JSON is unterminated. There is no difference if I surround the variable with single or double quotes.
Even if the whitespace is inside one of the two DateTime variables the problem occurs!
How can I format the JSON properly so that it can include whitespace?

Answer 1

Not a direct answer to your question, but since you're using PowerShell anyway: why not use the native Invoke-WebRequest instead of an external command?
$today = (Get-Date).Date
$uri = 'https://example.org/export/sales'
$headers = #{
'Content-Type' = 'application/json'
}
$data = #{
'ApiToken' = $apitoken
'StartDate' = $today.AddDays(-$startInterval).ToString('d')
'EndDate' = $today.ToString('d')
'Type' = 'SalesExport'
} | ConvertTo-Json
Invoke-WebRequest -Method Post -Headers $headers -Body $data -Uri $uri
Alternatively you can define the JSON data as a multiline string:
$startDate = $today.AddDays(-$startInterval).ToString('d')
$endDate = $today.ToString('d')
$data = #"
{
"ApiToken": "$apitoken",
"StartDate": "$startDate",
"EndDate": "$endDate",
"Type": "SalesExport"
}
"#