2378a5ff78
Replaces separate Url/User/Password inputs on NatsPublish and NatsTrigger with one Connection input in standard NATS URL form (e.g. nats://user:pass@host:4222, wss://user:pass@host/). The activity's input description explains the format so it renders as help text in the Studio property panel. NatsConnectionCache now parses the connection string, keeps its cache keyed on the parsed (url, user, password) tuple, and exposes ParseConnectionString for reuse. NatsTriggerStimulus collapses to (Connection, Stream, Subject); existing NATS workflows must be republished to re-index with the new stimulus shape.
79 lines
3.4 KiB
C#
79 lines
3.4 KiB
C#
using System.Text;
|
|
using Elsa.CustomServer.Nats;
|
|
using Elsa.Extensions;
|
|
using Elsa.Workflows;
|
|
using Elsa.Workflows.Attributes;
|
|
using Elsa.Workflows.Models;
|
|
using NATS.Client.Core;
|
|
using NATS.Client.JetStream;
|
|
using NATS.Client.JetStream.Models;
|
|
|
|
namespace Elsa.CustomServer.Activities;
|
|
|
|
[Activity("NATS", "NATS", "Publish a message to a NATS JetStream subject.", DisplayName = "NATS Publish", Kind = ActivityKind.Task)]
|
|
public class NatsPublish : CodeActivity
|
|
{
|
|
[Input(
|
|
DisplayName = "Connection string",
|
|
Description =
|
|
"NATS connection string. Format: <scheme>://[user:password@]host[:port]. " +
|
|
"Schemes: nats, tls, ws, wss. " +
|
|
"Examples: nats://demo.nats.io:4222 | nats://alice:s3cret@nats.example.com:4222 | " +
|
|
"wss://alice:s3cret@nats.example.com/. " +
|
|
"Special characters in the password must be URL-encoded (@ = %40, : = %3A, / = %2F, # = %23).",
|
|
Category = "Connection")]
|
|
public Input<string> Connection { get; set; } = default!;
|
|
|
|
[Input(Description = "Subject to publish to (must be bound to a JetStream stream).")]
|
|
public Input<string> Subject { get; set; } = default!;
|
|
|
|
[Input(Description = "Message body (UTF-8 string).")]
|
|
public Input<string> Body { get; set; } = default!;
|
|
|
|
[Input(Description = "Optional Nats-Msg-Id used by JetStream for server-side deduplication within the stream's duplicate window.")]
|
|
public Input<string?> MessageId { get; set; } = new(default(string?));
|
|
|
|
[Input(Description = "Optional stream name for a fail-fast assertion that the subject lands in this stream.")]
|
|
public Input<string?> ExpectedStream { get; set; } = new(default(string?));
|
|
|
|
[Output(Description = "Stream sequence number the server assigned to the accepted message.")]
|
|
public Output<long> Sequence { get; set; } = default!;
|
|
|
|
[Output(Description = "True when JetStream deduplicated (Nats-Msg-Id already seen within the duplicate window).")]
|
|
public Output<bool> Duplicate { get; set; } = default!;
|
|
|
|
protected override async ValueTask ExecuteAsync(ActivityExecutionContext context)
|
|
{
|
|
var connection = context.Get(Connection);
|
|
if (string.IsNullOrWhiteSpace(connection))
|
|
throw new InvalidOperationException("NatsPublish: Connection string is required.");
|
|
|
|
var subject = context.Get(Subject);
|
|
if (string.IsNullOrWhiteSpace(subject))
|
|
throw new InvalidOperationException("NatsPublish: Subject is required.");
|
|
|
|
var body = context.Get(Body) ?? string.Empty;
|
|
var messageId = context.Get(MessageId);
|
|
var expectedStream = context.Get(ExpectedStream);
|
|
|
|
var pool = context.GetRequiredService<NatsConnectionCache>();
|
|
var nats = pool.Get(connection);
|
|
var js = new NatsJSContext(nats);
|
|
|
|
NatsHeaders? headers = null;
|
|
if (!string.IsNullOrEmpty(messageId))
|
|
headers = new NatsHeaders { ["Nats-Msg-Id"] = messageId };
|
|
|
|
var opts = string.IsNullOrEmpty(expectedStream)
|
|
? null
|
|
: new NatsJSPubOpts { ExpectedStream = expectedStream };
|
|
|
|
var payload = Encoding.UTF8.GetBytes(body);
|
|
var ack = await js.PublishAsync(subject, payload, headers: headers, opts: opts, cancellationToken: context.CancellationToken);
|
|
ack.EnsureSuccess();
|
|
|
|
context.Set(Sequence, (long)ack.Seq);
|
|
context.Set(Duplicate, ack.Duplicate);
|
|
}
|
|
}
|