Validate dashboard sub to Slack creation (#14531)

[Fixes #14494]

frontend/src/metabase/lib/pulse.js

@@ -46,23 +46,25 @@ export function channelIsValid(channel, channelSpec) {
   return true;
 }
 
+function pulseChannelsAreValid(pulse, channelSpecs) {
+  return (
+    pulse.channels.filter(c =>
+      channelIsValid(c, channelSpecs && channelSpecs[c.channel_type]),
+    ).length > 0 || false
+  );
+}
+
 export function pulseIsValid(pulse, channelSpecs) {
   return (
     (pulse.name &&
       pulse.cards.length > 0 &&
-      pulse.channels.filter(c =>
-        channelIsValid(c, channelSpecs && channelSpecs[c.channel_type]),
-      ).length > 0) ||
+      pulseChannelsAreValid(pulse, channelSpecs)) ||
     false
   );
 }
 
 export function dashboardPulseIsValid(pulse, channelSpecs) {
-  return (
-    pulse.channels.filter(c =>
-      channelIsValid(c, channelSpecs && channelSpecs[c.channel_type]),
-    ).length > 0 || false
-  );
+  return pulseChannelsAreValid(pulse, channelSpecs);
 }
 
 export function emailIsEnabled(pulse) {

frontend/src/metabase/sharing/components/SharingSidebar.jsx

@@ -28,7 +28,11 @@ import User from "metabase/entities/users";
 
 import { connect } from "react-redux";
 
-import { cleanPulse, createChannel, pulseIsValid } from "metabase/lib/pulse";
+import {
+  cleanPulse,
+  createChannel,
+  dashboardPulseIsValid,
+} from "metabase/lib/pulse";
 import MetabaseSettings from "metabase/lib/settings";
 
 import {
@@ -604,7 +608,7 @@ class SharingSidebar extends React.Component {
           onClose={this.handleSave}
           onCancel={this.onCancel}
           className="text-dark"
-          closeIsDisabled={!pulseIsValid(pulse, formInput.channels)}
+          closeIsDisabled={!dashboardPulseIsValid(pulse, formInput.channels)}
         >
           <div className="pt4 px4 flex align-center">
             <Icon name="mail" className="mr1" size={21} />
@@ -705,6 +709,7 @@ class SharingSidebar extends React.Component {
           onClose={this.handleSave}
           onCancel={this.onCancel}
           className="text-dark"
+          closeIsDisabled={!dashboardPulseIsValid(pulse, formInput.channels)}
         >
           <div className="pt4 flex align-center px4 mb3">
             <Icon name="slack" className="mr1" size={21} />