Handle nan values and other non-serializable data in events from the …

…WebView tracker (#909)
snowplow · Nov 20, 2024 · 8f404b5 · 8f404b5
1 parent bf14959
commit 8f404b5
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diff --git a/Sources/Core/Tracker/WebViewMessageHandler.swift b/Sources/Core/Tracker/WebViewMessageHandler.swift
@@ -40,6 +40,11 @@ class WebViewMessageHandler: NSObject, WKScriptMessageHandler {
             let context = body["context"] as? [[AnyHashable : Any]] ?? []
             let trackers = body["trackers"] as? [String] ?? []
 
+            if !JSONSerialization.isValidJSONObject(event) || !JSONSerialization.isValidJSONObject(context) {
+                logError(message: "WebView: Received event payload is not serializable to JSON, skipping.")
+                return
+            }
+
             if command == "trackSelfDescribingEvent" {
                 trackSelfDescribing(event, withContext: context, andTrackers: trackers)
             } else if command == "trackStructEvent" {

diff --git a/Tests/TestWebViewMessageHandler.swift b/Tests/TestWebViewMessageHandler.swift
@@ -126,5 +126,41 @@ class TestWebViewMessageHandler: XCTestCase {
         let context = payload?["co"] as? String
         XCTAssert(context?.contains("{\"a\":\"b\"}") ?? false)
     }
+
+    func testHandlesNonJSONSerializableDataInEvent() {
+        let message = MockWKScriptMessage(
+            body: [
+                "command": "trackSelfDescribingEvent",
+                "event": [
+                    "schema": "http://schema.com",
+                    "data": [
+                        "key": Double.nan
+                    ]
+                ]
+            ])
+        webViewMessageHandler?.receivedMesssage(message) // shouldn't crash
+    }
+
+    func testHandlesNonJSONSerializableDataInContext() {
+        let message = MockWKScriptMessage(
+            body: [
+                "command": "trackSelfDescribingEvent",
+                "event": [
+                    "schema": "http://schema.com",
+                    "data": [
+                        "key": "val"
+                    ]
+                ],
+                "context": [
+                    [
+                        "schema": "http://context-schema.com",
+                        "data": [
+                            "a": Double.nan
+                        ]
+                    ]
+                ]
+            ])
+        webViewMessageHandler?.receivedMesssage(message) // shouldn't crash
+    }
 }
 #endif