1 files changed, 72 insertions, 0 deletions
diff --git a/api/nft-event-listener.nu b/api/nft-event-listener.nu
new file mode 100644
index 0000000..0554c6f
--- /dev/null
+++ b/api/nft-event-listener.nu
@@ -0,0 +1,72 @@
+def "job recv pending" []: nothing -> list {
+    "marker" | job send (job id) # send a marker to self
+    mut events = []
+    mut ev = job recv # marker will prevent wait here
+    while $ev != "marker" { 
+        $events = $events | append $ev
+        $ev = job recv 
+    }
+    $events
+}
+
+# may wait up to two intervals, because event timestamps are not accounted
+def create-debounce-queue [interval: duration, handler: closure] {
+    job spawn -d "debounce queue" {
+        mut event = job recv
+        loop {
+            sleep $interval
+            let new_events = job recv pending
+            if ($new_events | is-empty) {
+                do $handler $event
+                $event = job recv
+            } else {
+                $event = ($new_events | last)
+            }
+        }
+    }
+}
+
+def single [] {
+    let $data = $in
+    if ($data | length) != 1 {
+        make error "Expected single element"
+    }
+    $data | first
+}
+
+def parse-nft-mon-event [] {
+    mut rest = $in
+    mut result = {}
+    for key_name in ['action', 'type'] {
+        let key = $rest | items {|k, v| $k} | single
+        $rest = $rest | get $key
+        $result = $result | insert $key_name $key
+    }
+    $result | merge $rest
+}
+
+def main [--test] {
+    let debounce_interval = 2sec
+    let debounce_queue = create-debounce-queue $debounce_interval {|ev| 
+        print "Triggered" $ev
+        # nu update-netbird-nftables.nu --apply
+    }
+    try {
+        if $test {
+            nu test-data/mock-nft-mon.nu
+        } else {
+            ^nft --json monitor rules 
+        } | lines 
+            | each { from json | parse-nft-mon-event }
+            | where action == add and type == rule and table == netbird # TODO filter update evenets
+            | each { job send $debounce_queue } 
+            | ignore
+        print "Exiting gracefully..."
+        sleep $debounce_interval
+        sleep $debounce_interval
+    } catch { |e| 
+        print $e.rendered
+    } finally {
+        job kill $debounce_queue
+    }
+}
+\ No newline at end of file