clear slack token if saved with a non-existant files channel (#29397)

src/metabase/api/slack.clj

@@ -40,6 +40,10 @@
       (slack/clear-channel-cache!))
     (let [processed-files-channel (slack/process-files-channel-name slack-files-channel)]
       (when (and processed-files-channel (not (slack/channel-exists? processed-files-channel)))
+        ;; Files channel could not be found; clear the token we had previously set since the integration should not be
+        ;; enabled.
+        (slack/slack-token-valid?! false)
+        (slack/slack-app-token! nil)
         (throw (ex-info (tru "Slack channel not found.")
                         {:errors {:slack-files-channel (tru "channel not found")}})))
       (slack/slack-files-channel! processed-files-channel))

src/metabase/integrations/slack.clj

@@ -192,12 +192,13 @@
                         params)))
 
 (defn channel-exists?
-  "Returns true if the channel it exists."
+  "Returns a Boolean indicating whether a channel with a given name exists in the cache."
   [channel-name]
-  (let [channel-names (into #{} (comp (map (juxt :name :id))
-                                      cat)
-                            (:channels (slack-cached-channels-and-usernames)))]
-    (and channel-name (contains? channel-names channel-name))))
+  (boolean
+   (let [channel-names (into #{} (comp (map (juxt :name :id))
+                                       cat)
+                             (:channels (slack-cached-channels-and-usernames)))]
+     (and channel-name (contains? channel-names channel-name)))))
 
 (s/defn valid-token?
   "Check whether a Slack token is valid by checking if the `conversations.list` Slack api accepts it."

test/metabase/api/slack_test.clj

@@ -45,16 +45,22 @@
           (mt/user-http-request :crowberto :put 200 "slack/settings" {:slack-files-channel "#fake-channel"})
           (is (= "fake-channel" (slack/slack-files-channel))))))
 
-    (testing "An error is returned if the Slack files channel cannot be found"
-      (with-redefs [slack/channel-exists? (constantly nil)]
+    (testing "An error is returned if the Slack files channel cannot be found, and the integration is not enabled"
+      (with-redefs [slack/channel-exists?                             (constantly nil)
+                    slack/valid-token?                                (constantly true)
+                    slack/refresh-channels-and-usernames!             (constantly nil)
+                    slack/refresh-channels-and-usernames-when-needed! (constantly nil)]
         (let [response (mt/user-http-request :crowberto :put 400 "slack/settings"
-                                             {:slack-files-channel "fake-channel"})]
-          (is (= {:slack-files-channel "channel not found"} (:errors response))))))
+                                             {:slack-files-channel "fake-channel"
+                                              :slack-app-token     "fake-token"})]
+          (is (= {:slack-files-channel "channel not found"} (:errors response)))
+          (is (nil? (slack/slack-app-token)))
+          (is (= "metabase_files" (slack/slack-files-channel))))))
 
     (testing "The Slack app token or files channel settings are cleared if no value is sent in the request"
-      (mt/with-temporary-setting-values [slack-app-token "fake-token"
-                                         slack-files-channel "fake-channel"
-                                         slack/slack-cached-channels-and-usernames ["fake_channel"]
+      (mt/with-temporary-setting-values [slack-app-token                                 "fake-token"
+                                         slack-files-channel                             "fake-channel"
+                                         slack/slack-cached-channels-and-usernames       ["fake_channel"]
                                          slack/slack-channels-and-usernames-last-updated (t/zoned-date-time)]
         (mt/user-http-request :crowberto :put 200 "slack/settings" {})
         (is (= nil (slack/slack-app-token)))