Periodically look for a specific notification and close it in macOS

notification-killer.applescript.js

#!/usr/bin/env osascript -l JavaScript
// verify this logic using "Accessibility Inspector" of macOS if it's not working

TARGET_NOTIFICATION_TITLE_AND_BODY = ["<Set title here>", "<Set description here>"];

// generic utility functions
// -------------------------------------------------

// This function takes an element and returns a string array of all its immediate text children
function findAllTextChildren(element) {
  const textChildren = [];
  const children = element.uiElements();
  for (const child of children) {
    if (child.roleDescription() == "text") {
      textChildren.push(child.value());
    }
  }
  return textChildren;
}

// This function returns the first action of the specified element that has the specified action description
function findFirstActionChild(element, action_description) {
  const actions = element.actions();
  for (const action of actions) {
    if (action.description() == action_description) {
      return action;
    }
  }
  return null;
}

// notification specific functions
// -------------------------------------------------

// find scrollarea of the notification-center process
function findNotificationScrollingArea(process) {
  const windows = process.windows();
  if (windows.length == 0) {
    return;
  }
  
  const rootWindow = windows[0];

  // traverse into the first group
  const groups = rootWindow.groups();
  if (groups.length == 0) {
    console.log("No groups found in the root window.");
    return;
  }
  const firstGroup = groups[0];

  // traverse into the first group again
  const firstGroupChildren = firstGroup.groups();
  if (firstGroupChildren.length == 0) {
    console.log("No children found in the first group.");
    return;
  }
  const firstFirstGroup = firstGroupChildren[0];

  // traverse into the scroll area
  const scrollAreas = firstFirstGroup.scrollAreas();
  if (scrollAreas.length == 0) {
    console.log("No scroll areas found in the first-first group.");
    return;
  }
  const scrollArea = scrollAreas[0];
  
  return scrollArea;
}

// traverses through all active notification items found in the scrollArea,
// and closes those that its all texts (title, description) matches "target_texts"
function closeNotification(scrollArea, target_texts) {
  const scrollAreaGroups = scrollArea.groups();
  for (const notification of scrollAreaGroups) {
    if (notification.subrole() == "AXNotificationCenterAlert") {
      // fetch all text children of the group
      const texts = findAllTextChildren(notification);
      if (texts.toString() == target_texts.toString()) {
        console.log("Found a notification alert that matches.");

        const action = findFirstActionChild(notification, "Close");
        if (action) {          
          action.perform();
          return true;
        } else {
          console.log("Target notification alert does not have a close action.");
        }
      }
    } else if (notification.role() == "AXGroup") {
      if (closeNotification(notification, target_texts) == true) {
        return true;
      }
    }
  }
  return false;
}

// main!
// -------------------------------------------------

function run() {
  const systemEvents = Application("System Events");
  const process = systemEvents.applicationProcesses.byName("NotificationCenter");

  for (;;) {
    try {
      const scrollArea = findNotificationScrollingArea(process);
      if (scrollArea) {
        closeNotification(scrollArea, TARGET_NOTIFICATION_TITLE_AND_BODY);
      }
    } catch (e) {
      console.log('err: ', e)
    }
    delay(1);
  }
}

test scenario

// produce a notification by sending this to hammerspoon console
hs.notify.new({title = "test", subTitle = "something", withdrawAfter = 10000, }):send()

// change this variable in the script, run it, it'll close the notification
TARGET_NOTIFICATION_TITLE_AND_BODY = ["test", "something"]