Improve checking urls for URLProtocol usage

Author: tapwork

Sources/InstanaAgent/Monitors/HTTP/InstanaURLProtocol.swift

@@ -37,8 +37,11 @@ class InstanaURLProtocol: URLProtocol {
 
     override class func canInit(with request: URLRequest) -> Bool {
         guard mode == .enabled else { return false }
-        guard let url = request.url, let scheme = url.scheme, !IgnoreURLHandler.shouldIgnore(url) else { return false }
-        return ["http", "https"].contains(scheme)
+        guard request.url?.host != nil else { return false }
+        guard let url = request.url, let scheme = url.scheme else { return false }
+        guard ["http", "https"].contains(scheme) else { return false }
+        guard !IgnoreURLHandler.shouldIgnore(url) else { return false }
+        return true
     }
 
     private var canMark: Bool {

Tests/InstanaAgentTests/Monitors/HTTP/InstanaURLProtocolTests.swift

@@ -27,6 +27,17 @@ class InstanaURLProtocolTests: InstanaTestCase {
         XCTAssertTrue(InstanaURLProtocol.canInit(with: makeRequest("http://www.a.c")))
         XCTAssertFalse(InstanaURLProtocol.canInit(with: makeRequest("www.a.c")))
         XCTAssertFalse(InstanaURLProtocol.canInit(with: makeRequest("ws://a")))
+        XCTAssertFalse(InstanaURLProtocol.canInit(with: makeRequest("some:nohost")))
+    }
+
+    func test_urlProtocol_shouldNotInitForBase64() {
+        // Given
+        let base64 = "data:image/jpeg;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAMAAAAoLQ9TAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAAwBQTFRF7c5J78kt+/Xm78lQ6stH5LI36bQh6rcf7sQp67="
+        let request = makeRequest(base64)
+
+        // Then
+        XCTAssertFalse(InstanaURLProtocol.canInit(with:request))
+        XCTAssertEqual(request.url?.absoluteString, base64)
     }
 
     func test_urlProtocol_shouldNotInitForIgnoredURL() {