PsDotNet.Kevlar 2.4.0

PsDotNet.Kevlar

Async .NET client for Adobe Photoshop's Remote Connection TCP protocol — run ExtendScript, fetch pixel thumbnails, and receive event notifications from any .NET 8 application on Windows.

This is a companion package to PsDotNet, not a replacement. PsDotNet automates Photoshop via COM (in-process, rich object model). Kevlar speaks the Remote Connection wire protocol over TCP — the same channel used by Adobe's own Creative Cloud extensions. The two approaches are complementary: COM for deep automation on the same machine; Kevlar for lightweight remote or cross-process scripting, thumbnail extraction, and live event feeds.

dotnet add package PsDotNet.Kevlar

Quick start

using PsDotNet.Kevlar;

// Connect to Photoshop's Remote Connection listener (default port 49494).
// Enable it in Photoshop: Edit > Preferences > Plug-Ins > Enable Remote Connections.
await using PhotoshopConnection conn =
    await PhotoshopConnection.ConnectAsync("localhost", 49494, "mypassword");

// Run an ExtendScript expression and get the result back as a string.
string version = await conn.SendScriptAsync("app.version;");
Console.WriteLine($"Photoshop version: {version}");

// Fetch a bitmap thumbnail of the active document (returns a System.Drawing.Bitmap).
System.Drawing.Bitmap thumb = await conn.GetThumbnailAsync();

// Subscribe to live Photoshop events.
conn.NotificationReceived += (_, e) =>
    Console.WriteLine($"[{e.Notification}] {e.Payload}");

await conn.SubscribeEventsAsync(new[]
{
    PhotoshopNotification.documentChanged,
    PhotoshopNotification.currentDocumentChanged,
});

// Keep the process alive while Photoshop sends events …
await Task.Delay(Timeout.Infinite);

Windows only

PsDotNet.Kevlar targets net8.0-windows. It depends on System.Drawing.Common (for Bitmap) which requires Windows. The package will not restore on non-Windows targets.

Requirements

• Windows
• .NET 8 or newer
• Adobe Photoshop with Remote Connections enabled (Edit > Preferences > Plug-Ins > Enable Remote Connections)

Security

Read before deploying outside a trusted network.

Adobe's Remote Connection protocol has several inherent cryptographic weaknesses that this library faithfully implements in order to interoperate with Photoshop:

These weaknesses are mandated by Adobe's wire protocol — they are not design choices of this library. Kevlar cannot fix them without breaking compatibility with Photoshop.

Recommended use: localhost or isolated LAN where you fully trust all hosts. Do not expose port 49494 to the public internet or to untrusted networks.

License

MIT — see https://github.com/nodewerks/psdotnet/blob/main/LICENSE.