Slack

Sign in with Slack accounts using OpenID Connect.

1. Create OAuth App

1. Go to Slack API — Your Apps.
2. Click Create New App > From scratch.
3. Enter your app name and select a workspace, then click Create App.
4. Go to OAuth & Permissions in the left sidebar.
5. Under Redirect URLs, add your EdgeBase callback URL (see below), click Add, then click Save URLs.
6. Under Scopes > User Token Scopes, add:
   • openid
   • email
   • profile
7. Click Install to Workspace (or reinstall if you changed redirect URLs or scopes).

2. Set Redirect URI

Add your EdgeBase callback URL under OAuth & Permissions > Redirect URLs:

https://your-edgebase-url/api/auth/oauth/slack/callback

For local development:

Use an HTTPS tunnel that forwards to your local EdgeBase auth server, for example:

https://your-tunnel.example/api/auth/oauth/slack/callback

As of March 8, 2026, Slack's app console requires redirect URLs to begin with https://, so plain http://localhost:8787/... is rejected in the UI. A local tunnel such as cloudflared or ngrok is the practical approach for browser-based local testing.

3. Get Credentials

In Basic Information:

• Client ID — Listed as your app's Client ID.
• Client Secret — Listed as your app's Client Secret.

Do Not Use the User OAuth Token

Slack also shows a User OAuth Token on the OAuth & Permissions page after installation. That token is not the clientSecret for EdgeBase. Use the Client ID and Client Secret from Basic Information.

4. Configure EdgeBase

// edgebase.config.ts
export default defineConfig({
  auth: {
    allowedOAuthProviders: ['slack'],
  },
});

export default defineConfig({
  auth: {
    oauth: {
      slack: {
        clientId: 'YOUR_CLIENT_ID',
        clientSecret: 'YOUR_CLIENT_SECRET',
      },
    },
  },
});

5. Usage

JavaScript

client.auth.signInWithOAuth('slack');

Dart/Flutter

await client.auth.signInWithOAuth('slack');

Swift

let url = client.auth.signInWithOAuth(provider: "slack")
// Open url in SFSafariViewController or ASWebAuthenticationSession

Kotlin

client.auth.signInWithOAuth("slack")

Java

client.auth().signInWithOAuth("slack");

C#

client.Auth.SignInWithOAuth("slack");

C++

OAuth requires a browser redirect flow. For C++ (Unreal Engine), handle OAuth in a platform webview and pass the token to the SDK.

Provider Details

Property	Value
Scopes	openid email profile
PKCE	No
Email	Yes
Email verified	Always true (Slack policy)
Avatar	Yes — picture URL
Refresh token	No

Notes

• Slack uses OpenID Connect (not standard OAuth2), so the endpoints are openid.connect.authorize and openid.connect.token.
• Slack emails are always considered verified (email_verified is always true), so automatic account linking with existing email accounts will work.
• The user ID comes from the sub claim in the OpenID Connect response.
• Your app must be installed to a workspace, but users from any workspace can sign in if your app is distributed.
• Use User Token Scopes, not Bot Token Scopes, for Slack sign-in.
• If Slack says the redirect URL must start with https://, that is expected in the current console UI. Use an HTTPS tunnel for local browser testing.
• Local verification was completed on March 8, 2026 using an HTTPS tunnel callback and the js-web browser harness. The current result was 7 passed / 2 skipped, where the skipped items were the intentional passkey reuse / no-auto-delete checks.