SmallestDotNet

SmallestDotNet - SmallestDotNet.com is a single page site that does one thing. It tells you the smallest, easiest download you'd need to get the .NET Framework on your system.

It currently recommends .NET Framework 4.8.1 for machines that need the latest .NET Framework runtime. For new development, use modern .NET instead.

The code sucks. I did it in an hour and I'm sad.

Thanks to Calin Balauru for his help. Anything good here is him. All the bad is me.

Current production app

Production now runs from SmallestDotNetModern, an ASP.NET Core app targeting .NET 10. The original Web Forms project is still in the repository for reference, but the live site is the Linux App Service app:

• Azure subscription: Scott's Main Azure Account (MSDN)
• Resource group: HanselmanDotComLinux
• App Service app: smallestdotnet-linux
• App Service plan: HanselmanLinux
• Runtime: DOTNETCORE|10.0
• Hostnames: smallestdotnet.com, smallestdotnet-linux.azurewebsites.net
• TLS: Azure App Service managed certificate bound with SNI
• DNS: hosted at DNSimple, not Azure DNS

There is not currently a GitHub/Git deployment wired up for the Azure app. The app's deployment source is None; the production deployment was done manually with a prebuilt zip package and App Service zip deploy.

Project layout

• SmallestDotNetModern - production ASP.NET Core/.NET 10 app. It preserves the original public routes, including /, /VersionCheck.ashx, /javascript.ashx, /javascriptdom.ashx, and the old /smallestdotnet/... redirects.
• SmallestDotNetModernLib - SDK-style .NET 10 wrapper that links the original detection source files.
• SmallestDotNetLib - original .NET Framework detection and output logic. Keep framework release keys and download URLs current here.
• SmallestDotNet - original ASP.NET Web Forms app, kept for history/reference.
• CheckForDotNet45 - helper executable that reads the .NET Framework registry release key and returns to the website.
• SmallestTest - legacy MSTest coverage for the detection and JavaScript output behavior.

.NET checker executable

The " .NET Checker" download is CheckForDotNet45.exe, built from CheckForDotNet45\Program.cs and hosted outside the App Service at:

https://hanselstorage.blob.core.windows.net/blog/CheckForDotNet45.exe

The App Service deployment does not update this blob. The current binary is intentionally simple: it reads the .NET Framework Release registry value and opens https://smallestdotnet.com/?releaseKey=<value>. Because version mapping happens on the website, the binary usually does not need to be rebuilt when new release keys are added to Constants.ReleaseVersions.

If the executable is rebuilt, upload the new binary to the blob URL above and verify the site still links there. The currently hosted binary is not Authenticode-signed, so the website should not claim that it is code signed unless a signed replacement is uploaded.

Framework data maintenance

The site intentionally focuses on .NET Framework, not modern .NET. New application development should use current .NET, but this site exists for people who need to run or detect .NET Framework.

When Microsoft adds or documents new .NET Framework release keys, update:

• Constants.ReleaseVersions for checker release-key detection.
• Constants.DotNet, download URLs, and download sizes if the latest recommended .NET Framework runtime changes.
• CLRVersions.Versions if /javascriptdom.ashx should advertise additional downloadable framework versions.
• SmallestTest expectations for release keys and JavaScript payloads.

Manual deployment

Build and publish the modern app from the repository root:

Remove-Item -Recurse -Force .\artifacts -ErrorAction SilentlyContinue
dotnet publish .\SmallestDotNetModern\SmallestDotNetModern.csproj -c Release -o .\artifacts\SmallestDotNetModern-publish
Compress-Archive -Path .\artifacts\SmallestDotNetModern-publish\* -DestinationPath .\artifacts\SmallestDotNetModern.zip -Force

Deploy the zip to Azure App Service:

az account set --subscription "Scott's Main Azure Account (MSDN)"

$sub = az account show --query id -o tsv
$rg = "HanselmanDotComLinux"
$app = "smallestdotnet-linux"
$siteId = "/subscriptions/$sub/resourceGroups/$rg/providers/Microsoft.Web/sites/$app"

az resource update --ids "$siteId/basicPublishingCredentialsPolicies/scm" --set properties.allow=true

try {
    [xml]$profiles = az webapp deployment list-publishing-profiles -g $rg -n $app --xml
    $profile = @($profiles.publishData.publishProfile | Where-Object { $_.publishMethod -eq "ZipDeploy" })[0]
    $pair = "$($profile.userName):$($profile.userPWD)"
    $headers = @{ Authorization = "Basic " + [Convert]::ToBase64String([Text.Encoding]::ASCII.GetBytes($pair)) }

    Invoke-WebRequest `
        -Uri "https://$app.scm.azurewebsites.net/api/zipdeploy" `
        -Headers $headers `
        -Method Post `
        -InFile .\artifacts\SmallestDotNetModern.zip `
        -ContentType "application/zip" `
        -UseBasicParsing

    az webapp restart -g $rg -n $app
}
finally {
    az resource update --ids "$siteId/basicPublishingCredentialsPolicies/scm" --set properties.allow=false
}

Validate the public endpoints after deploy:

Invoke-WebRequest https://smallestdotnet.com/
Invoke-WebRequest https://smallestdotnet.com/?releaseKey=528040
Invoke-WebRequest https://smallestdotnet.com/?realversion=4.8
Invoke-WebRequest https://smallestdotnet.com/VersionCheck.ashx?userAgent=Mozilla%2F5.0
Invoke-WebRequest https://smallestdotnet.com/javascript.ashx
Invoke-WebRequest https://smallestdotnet.com/javascriptdom.ashx

If deployment is automated later, prefer GitHub Actions with OIDC or an Azure publish profile stored as a repository secret. Until then, keep SCM basic publishing disabled except during the short zip deploy window.

License