Possibly a few different ways to do this, but I'd try using an AngularJs HTTP interceptor, to capture requests to the /postsave endpoint where the action is publish.

Pretty sure the request includes the complete content item, so you'd be able to check the content type, extract any property values, and do with them whatever you need.

The interceptor is simply a service factory with request and response methods (only interested in request in this example):

(() => {
    function interceptor($q) {
        return {
            request: req => {
                if (// my condition is true) {
                    // do something with the content
                    // if it's not attached to the request, you could get it from editorState.current
                }
                return req || $q.when(req);
            }
        };
    }

    angular.module('umbraco').factory('myInterceptor', ['$q', interceptor]);

    angular.module('umbraco')
        .config(function($httpProvider) {
            $httpProvider.interceptors.push('myInterceptor');
        });  
})();

HI,

Don't know what the reason is why you want to do this client side?

I tend to do these kind of things server side hooking in to the content service events

https://our.umbraco.org/documentation/Reference/Events/ContentService-Events

Dave

in the Performsave of the umbracoController.js you can broadcast an event which can be triggered in a custom plugin.

function performSave(args) {
    var deferred = $q.defer();

    $scope.page.buttonGroupState = "busy";

    contentEditingHelper.contentEditorPerformSave({
        statusMessage: args.statusMessage,
        saveMethod: args.saveMethod,
        scope: $scope,
        content: $scope.content,
        action: args.action
    }).then(function (data) {
        //success            
        init($scope.content);
        syncTreeNode($scope.content, data.path);

        $scope.page.buttonGroupState = "success";

        // REWRITE
        // We add an event to enable the language fallback controller
        // To reload the current language state
        $scope.$broadcast("contentHasBeenSubmited");

        deferred.resolve(data);
    }, function (err) {
        //error
        if (err) {
            editorState.set($scope.content);
        }

        $scope.page.buttonGroupState = "error";

        deferred.reject(err);
    });

    return deferred.promise;
}

In your plugin you can inject the editorState where you can get the current one with editorState.getCurrent(). You can check the object to see the properties. Hereby a sample

const languagefallbackController = function ($scope, $timeout, editorState) {
        var currentEditorState = editorState.getCurrent();
        var contentId = currentEditorState.id;
        var alias = currentEditorState.contentTypeAlias;
        var somevalue = currentEditorState.tabs[0].properties[0].value.values;

        // This event is customly added to the Umbraco.Editors.Content.EditController
       // this enable us to reload the control when content has been submitted
       $scope.$on("contentHasBeenSubmited", function () {
            // do your stuff here
       });
    });
}

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