windmill-labs/windmill · error

e (Slack chat.update request error propagated via anyhow)

Error message

e (Slack chat.update request error propagated via anyhow)

What it means

`update_original_slack_message` edits the original approval/interactivity message in Slack via `POST https://slack.com/api/chat.update`. Network or transport failures on `.send()` (DNS failure, connection reset, timeout) are propagated as anyhow errors wrapping the reqwest error. Note: HTTP-level errors from Slack's API (non-2xx responses with an `error` body like `message_not_found` or `invalid_auth`) are logged, not thrown — this specific error is the request-level failure path.

Source

Thrown at backend/windmill-api/src/slack_approvals.rs:1228

    let payload = serde_json::json!({
        "channel": container.channel_id,
        "ts": container.message_ts,
        "text": message,
        "blocks": final_blocks,
        "mrkdwn": true // Enable markdown to support emojis
    });

    let client = Client::new();

    let response = client
        .post("https://slack.com/api/chat.update")
        .bearer_auth(token) // Use the token for authentication
        .header("Content-Type", "application/json")
        .json(&payload)
        .send()
        .await
        .map_err(|e| Error::from(anyhow::Error::new(e)))?;

    if response.status().is_success() {
        tracing::debug!("Slack message updated successfully!");
    } else {
        tracing::error!(
            "Failed to update Slack message. Status: {}, Response: {:?}",
            response.status(),
            response
                .text()
                .await
                .map_err(|e| Error::from(anyhow::Error::new(e)))?
        );
    }

    Ok(())
}

View on GitHub (pinned to e474e8803c)

Solutions

1. Verify the worker/API server has outbound HTTPS access to slack.com (curl https://slack.com/api/api.test from the host)
2. Check corporate proxy/firewall rules and set HTTPS_PROXY if required
3. Retry the submission — transport errors to Slack are often transient
4. Confirm the failure is transport-level (this error) vs a Slack API error (logged, e.g. invalid token), and check token validity for the latter

// preflight: can the server reach Slack?
const ok = await fetch("https://slack.com/api/api.test").then(r => r.ok).catch(() => false);
if (!ok) throw new Error("No outbound access to slack.com");

try {
  await updateOriginalSlackMessage(...);
} catch (e) {
  // transport-level failure: check egress/proxy, then retry with backoff
  await backoff(() => updateOriginalSlackMessage(...), 3);
}

When it happens

Trigger: A Slack form submission handler (`handle_submission`) tries to update the original message but the HTTPS request to Slack fails at the transport layer: no outbound network access, DNS resolution failure, TLS issues, or Slack returning a 5xx/timeout at the connection level.

Common situations: Self-hosted Windmill instances without internet egress, firewalls/proxies blocking slack.com, transient Slack outages, DNS misconfiguration in containers.

Understand the failure class

Background: ECONNREFUSED and "connection refused" / "could not connect to server" errors: what they mean and how to fix them — this error's family across 44 libraries.

Related errors

• Error executing get request from authed http client to {url}
• Error streaming get request from authed http client to {url}
• ApiError with mapped HTTP status message (e.g. "Not Found",
• Generic Error: status: ${errorStatus}; status text: ${errorS
• Couldn't fetch resource types from hub ${hubBaseUrl}: ${(awa

AI-assisted analysis of windmill-labs/windmill@e474e8803c (2026-09-03). Data as JSON: /api/errors/e0daa7fc5e283caf. Report an issue: GitHub.