first cut at slack oauth flow (#3323)

* first cut at slack oauth flow

* fix usage of hooks

* fix button spacing

* add additional error logging

* no dev redirect

* cleanup

* comment work in progress

* move some stuff to ee, add some playwright tests for the oauth callback edge cases

* fix ee, fix test name

* fix tests

* code review fixes

web/tests/e2e/admin_oauth_redirect_uri.spec.ts

@@ -0,0 +1,65 @@
+import { test, expect } from "@chromatic-com/playwright";
+
+test(
+  "Admin - OAuth Redirect - Missing Code",
+  {
+    tag: "@admin",
+  },
+  async ({ page }, testInfo) => {
+    await page.goto(
+      "http://localhost:3000/admin/connectors/slack/oauth/callback?state=xyz"
+    );
+
+    await expect(page.locator("p.text-text-500")).toHaveText(
+      "Missing authorization code."
+    );
+  }
+);
+
+test(
+  "Admin - OAuth Redirect - Missing State",
+  {
+    tag: "@admin",
+  },
+  async ({ page }, testInfo) => {
+    await page.goto(
+      "http://localhost:3000/admin/connectors/slack/oauth/callback?code=123"
+    );
+
+    await expect(page.locator("p.text-text-500")).toHaveText(
+      "Missing state parameter."
+    );
+  }
+);
+
+test(
+  "Admin - OAuth Redirect - Invalid Connector",
+  {
+    tag: "@admin",
+  },
+  async ({ page }, testInfo) => {
+    await page.goto(
+      "http://localhost:3000/admin/connectors/invalid-connector/oauth/callback?code=123&state=xyz"
+    );
+
+    await expect(page.locator("p.text-text-500")).toHaveText(
+      "invalid-connector is not a valid source type."
+    );
+  }
+);
+
+test(
+  "Admin - OAuth Redirect - No Session",
+  {
+    tag: "@admin",
+  },
+  async ({ page }, testInfo) => {
+    await page.goto(
+      "http://localhost:3000/admin/connectors/slack/oauth/callback?code=123&state=xyz"
+    );
+
+    await expect(page.locator("p.text-text-500")).toHaveText(
+      "An error occurred during the OAuth process. Please try again."
+    );
+  }
+);