prevent users from toggling metabot on/off if they don't have a valid slack token. fixes #2272

frontend/src/admin/settings/components/SettingsSetting.jsx

@@ -59,7 +59,7 @@ export default class SettingsSetting extends Component {
         var on = (setting.value == null ? setting.default : setting.value) === "true";
         return (
             <div className="flex align-center pt1">
-                <Toggle value={on} onChange={this.props.updateSetting.bind(null, setting, on ? "false" : "true")}/>
+                <Toggle value={on} onChange={!this.props.disabled ? this.props.updateSetting.bind(null, setting, on ? "false" : "true") : null}/>
                 <span className="text-bold mx1">{on ? "Enabled" : "Disabled"}</span>
             </div>
         );

frontend/src/admin/settings/components/SettingsSlackForm.jsx

@@ -174,6 +174,7 @@ export default class SettingsSlackForm extends Component {
                         key={element.key}
                         setting={_.extend(element, {value, errorMessage })}
                         updateSetting={(setting, value) => this.handleChangeEvent(setting, value)}
+                        disabled={!this.state.formData["slack-token"]}
                     />
                 );
             }

frontend/src/components/Toggle.jsx

@@ -24,7 +24,7 @@ export default class Toggle extends Component {
             <a
                 className={cx("Toggle", "no-decoration", { selected: this.props.value }) + " " + (this.props.className||"")}
                 style={{color: this.props.color || null}}
-                onClick={this.onClick}
+                onClick={this.props.onChange ? this.onClick : null}
             />
         );
     }