KTOR-550 Fix MDC exception crash request (#3143)

ktorio · Aug 31, 2022 · 9bf1ff9 · 9bf1ff9
1 parent e638b15
commit 9bf1ff9
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Showing 2 changed files with 29 additions and 1 deletion.
diff --git a/...ugins/ktor-server-call-logging/jvm/src/io/ktor/server/plugins/callloging/MDCEntryUtils.kt b/...ugins/ktor-server-call-logging/jvm/src/io/ktor/server/plugins/callloging/MDCEntryUtils.kt
@@ -29,7 +29,8 @@ internal fun List<MDCEntry>.setup(call: ApplicationCall): Map<String, String> {
     val result = HashMap<String, String>()
 
     forEach { entry ->
-        entry.provider(call)?.let { mdcValue ->
+        val provider = runCatching { entry.provider(call) }.getOrNull()
+        provider?.let { mdcValue ->
             result[entry.name] = mdcValue
         }
     }

diff --git a/ktor-server/ktor-server-plugins/ktor-server-call-logging/jvm/test/CallLoggingTest.kt b/ktor-server/ktor-server-plugins/ktor-server-call-logging/jvm/test/CallLoggingTest.kt
@@ -5,6 +5,7 @@
 package io.ktor.server.plugins.callloging
 
 import io.ktor.client.request.*
+import io.ktor.client.statement.*
 import io.ktor.http.*
 import io.ktor.server.application.*
 import io.ktor.server.engine.*
@@ -371,6 +372,32 @@ class CallLoggingTest {
         assertTrue("INFO: 404 Not Found: GET - /" in messages)
     }
 
+    @Test
+    fun `mdc exception does not crash request`() = testApplication {
+        var failed = 0
+        install(CallLogging) {
+            mdc("bar") {
+                failed++
+                throw Exception()
+            }
+            mdc("foo") { "Hello" }
+        }
+
+        routing {
+            get {
+                call.respond("OK")
+            }
+        }
+
+        assertEquals(0, failed)
+
+        assertEquals("OK", client.get("/").bodyAsText())
+        assertEquals(3, failed)
+
+        assertEquals("OK", client.get("/").bodyAsText())
+        assertEquals(6, failed)
+    }
+
     private fun green(value: Any): String = colored(value, Ansi.Color.GREEN)
     private fun red(value: Any): String = colored(value, Ansi.Color.RED)
     private fun cyan(value: Any): String = colored(value, Ansi.Color.CYAN)