Empty body content when doing a PUT request to Wiki pages - rest

Question

Azure DevOps Services REST API 5.0 - Wiki Pages
I'm trying to dynamically update an Azure DevOps Wiki page with the newest commits on top whenever a change is introduced to a repository.
When I try to PUT the commit history into a Wiki page the content field within the body is empty.
The request is done via Powershell and looks like this:
function postToWiki($Commits) {
$wikiUrl = "https://dev.azure.com/$organization/$project/_apis/wiki/wikis/Ekonomiredovisning.wiki/pages?path=MyWikiPage&api-version=5.0"
$Etag = getWikiPageVersion
$headers = #{
Authorization = "Bearer $env:SYSTEM_ACCESSTOKEN";
'If-Match' = $Etag}
$body = #{ content = $Commits }
$json = $body | ConvertTo-Json
Invoke-WebRequest -Uri $wikiUrl -Headers $headers -Body $json -ContentType "application/json" -Method Put
}
Additional information that can be useful:
It works when I send simpler strings like "Hello"
The JSON being sent is valid according to https://jsonlint.com/.
The $Commit variable is pretty huge, up to 6000 lines.

Answer 1

I have the same problem today. My body contained special HTML caracters wich are not escaped in the request.
Try to escape the special chars (éè...).
In PowerShell, you can use the following assembly:
Add-Type -AssemblyName System.Web
$encodedBody = [System.Web.HttpUtility]::HtmlEncode($Commits)
Result:
# Construct the wiki REST URI
# $uri = $WikiUri +$WikiPath + $($contentPackage.version)
$uri = "$($env:WikiUri)$($contentPackage)&api-version=5.0"
# Encode and convert to json
Add-Type -AssemblyName System.Web
$encodedContent = [System.Web.HttpUtility]::HtmlEncode($content)
$data = #{ Content=$encodedContent; } | ConvertTo-Json;
# Set Request
$params = #{uri = "$($uri)";
Method = 'PUT';
Headers = $header;
ContentType = "application/json";
Body = $data;
}
# Call
Invoke-WebRequest #params