Rewrite general weather alerts filter

weather/alerts_filter.js

@@ -3,56 +3,51 @@ const tornadoWarningEvents = ["Tornado Warning","Radar Indicated Tornado Warning
 
 let alerts = msg.payload
 
-// Filter for Severe Thunderstorm Warnings
+// Helper function to safely access nested properties
+const getNestedProperty = (obj, path, defaultValue = undefined) => {
+    return path.reduce((acc, key) => (acc && acc[key] !== undefined ? acc[key] : defaultValue), obj)
+}
 
-let ts = alerts.filter(function(alert) {
-    if (alert.raw.properties &&
-    severeWarningEvents.includes(alert.raw.properties.event)) {
-        return true
+// Filter function
+const filterAlerts = (alerts, condition) => {
+    return alerts.filter(alert => {
+        try {
+            return condition(alert)
+        } catch (e) {
+            node.warn(`Error processing alert: ${e.message}`)
+            return false
         }
     })
-
-// Filter for Severe Thunderstorm Warnings with tornado detection
-// that have a tornado possible parameter
-
-let tstp = alerts.filter(function(alert) {
-    if (alert.raw.properties &&
-    severeWarningEvents.includes(alert.raw.properties.event) &&
-    alert.raw.properties.parameters &&
-    alert.raw.properties.parameters.tornadoDetection &&
-    alert.raw.properties.parameters.tornadoDetection.length > 0) {
-        let tornadoPossible = alert.raw.properties.parameters.tornadoDetection[0]
-        return tornadoPossible === "POSSIBLE"
 }
+
+// Filtering logic
+const ts = filterAlerts(alerts, alert => {
+    const event = getNestedProperty(alert, ['raw', 'properties', 'event'])
+    return severeWarningEvents.includes(event)
 })
 
-// Filter for considerable destructive severe thunderstorm warnings
-
-let cdst = alerts.filter(function(alert) {
-    if (alert.raw.properties &&
-    alert.raw.properties.event === "Considerable Destructive Severe Thunderstorm Warning") {
-        return true
-    }
+const tstp = filterAlerts(alerts, alert => {
+    const event = getNestedProperty(alert, ['raw', 'properties', 'event'])
+    const tornadoDetection = getNestedProperty(alert, ['raw', 'properties', 'parameters', 'tornadoDetection'], [])
+    return severeWarningEvents.includes(event) && tornadoDetection.includes("POSSIBLE")
 })
 
-// Filter for Tornado Warnings
-
-let tornado = alerts.filter(function(alert) {
-    if (alert.raw.properties &&
-    tornadoWarningEvents.includes(alert.raw.properties.event)) {
-        return true
-    }
+const cdst = filterAlerts(alerts, alert => {
+    const event = getNestedProperty(alert, ['raw', 'properties', 'event'])
+    return event === "Considerable Destructive Severe Thunderstorm Warning"
 })
 
-let confirmed_tornado = alerts.filter(function(alert) {
-    if (alert.raw.properties &&
-    alert.raw.properties.event === "Confirmed Tornado Warning") {
-        return true
-    }
+const tornado = filterAlerts(alerts, alert => {
+    const event = getNestedProperty(alert, ['raw', 'properties', 'event'])
+    return tornadoWarningEvents.includes(event)
 })
 
-// If there are any alerts, return them
+const confirmed_tornado = filterAlerts(alerts, alert => {
+    const event = getNestedProperty(alert, ['raw', 'properties', 'event'])
+    return event === "Confirmed Tornado Warning"
+})
 
+// Output messages
 let tstormMsg = {
     "payload": {
         "alerts": ts,