Polish redacting Dynatrace token in error logs

Author: jonatan-ivanov

implementations/micrometer-registry-dynatrace/src/main/java/io/micrometer/dynatrace/v1/DynatraceExporterV1.java

@@ -53,8 +53,8 @@
  */
 public class DynatraceExporterV1 extends AbstractDynatraceExporter {
 
-    private static final int MAX_MESSAGE_SIZE = 15360; // max message size in bytes that
-                                                       // Dynatrace will accept
+    // max message size in bytes that Dynatrace will accept
+    private static final int MAX_MESSAGE_SIZE = 15360;
 
     private final InternalLogger logger = InternalLoggerFactory.getInstance(DynatraceExporterV1.class);
 
@@ -194,12 +194,10 @@ void putCustomMetric(final DynatraceMetricDefinition customMetric) {
                     .withJsonContent(customMetric.asJson());
         }
         catch (Exception ex) {
-            // log only the error message without the token
             if (logger.isErrorEnabled()) {
                 logger.error("failed to build request: {}", redactToken(ex.getMessage()));
             }
-            // do not attempt to export if the creation of the request already failed
-            return;
+            return; // don't try to export data points, the request can't be built
         }
 
         HttpSender.Response httpResponse = trySendHttpRequest(requestBuilder);
@@ -225,9 +223,8 @@ private void postCustomMetricValues(String type, String group, List<DynatraceTim
                 if (logger.isErrorEnabled()) {
                     logger.error("failed to build request: {}", redactToken(ex.getMessage()));
                 }
-                // don't export the other data points, since the endpoint will always be
-                // invalid.
-                return;
+
+                return; // don't try to export data points, the request can't be built
             }
 
             HttpSender.Response httpResponse = trySendHttpRequest(requestBuilder);
@@ -249,17 +246,15 @@ private void postCustomMetricValues(String type, String group, List<DynatraceTim
 
     // VisibleForTesting
     HttpSender.Response trySendHttpRequest(HttpSender.Request.Builder requestBuilder) {
-        HttpSender.Response httpResponse;
         try {
-            httpResponse = requestBuilder.send();
+            return requestBuilder.send();
         }
         catch (Throwable e) {
             if (logger.isErrorEnabled()) {
                 logger.error("failed to send metrics to Dynatrace: {}", redactToken(e.getMessage()));
             }
             return null;
         }
-        return httpResponse;
     }
 
     // VisibleForTesting
@@ -314,8 +309,8 @@ private Meter.Id idWithSuffix(Meter.Id id, String suffix) {
         return id.withName(id.getName() + "." + suffix);
     }
 
-    private String redactToken(String s) {
-        return s.replace(config.apiToken(), "<redacted>");
+    private String redactToken(String message) {
+        return message.replace(config.apiToken(), "<redacted>");
     }
 
 }

implementations/micrometer-registry-dynatrace/src/test/java/io/micrometer/dynatrace/v1/DynatraceExporterV1Test.java

@@ -266,16 +266,21 @@ void whenAllTsTooLargeEmptyMessageListReturned() {
 
     @Test
     void splitsWhenExactlyExceedingMaxByComma() {
+        // @formatter:off
         // comma needs to be considered when there is more than one time series
-        List<DynatraceBatchedPayload> messages = exporter.createPostMessages("my.type", "my.group",
+        List<DynatraceBatchedPayload> messages = exporter.createPostMessages(
+                "my.type",
+                "my.group",
                 // Max bytes: 15330 (excluding header/footer, 15360 with header/footer)
-                Arrays.asList(createTimeSeriesWithDimensions(750), // 14861 bytes
-                        createTimeSeriesWithDimensions(23, "asdfg"), // 469 bytes
-                        // (overflows due to
-                        // comma)
+                Arrays.asList(
+                        createTimeSeriesWithDimensions(750), // 14861 bytes
+                        // 469 bytes (overflows due to comma)
+                        createTimeSeriesWithDimensions(23, "asdfg"),
                         createTimeSeriesWithDimensions(750), // 14861 bytes
                         createTimeSeriesWithDimensions(22, "asd") // 468 bytes + comma
-                ));
+                )
+        );
+        // @formatter:on
         assertThat(messages).hasSize(3);
         assertThat(messages.get(0).metricCount).isEqualTo(1);
         assertThat(messages.get(1).metricCount).isEqualTo(1);
@@ -286,14 +291,19 @@ void splitsWhenExactlyExceedingMaxByComma() {
 
     @Test
     void countsPreviousAndNextComma() {
-        List<DynatraceBatchedPayload> messages = exporter.createPostMessages("my.type", null,
+        // @formatter:off
+        List<DynatraceBatchedPayload> messages = exporter.createPostMessages(
+                "my.type",
+                null,
                 // Max bytes: 15330 (excluding header/footer, 15360 with header/footer)
-                Arrays.asList(createTimeSeriesWithDimensions(750), // 14861 bytes
+                Arrays.asList(
+                        createTimeSeriesWithDimensions(750), // 14861 bytes
                         createTimeSeriesWithDimensions(10, "asdf"), // 234 bytes + comma
-                        createTimeSeriesWithDimensions(10, "asdf") // 234 bytes + comma =
-                // 15331 bytes
-                // (overflow)
-                ));
+                        // 234 bytes + comma = 15331 bytes (overflow)
+                        createTimeSeriesWithDimensions(10, "asdf")
+                )
+        );
+        // @formatter:on
         assertThat(messages).hasSize(2);
         assertThat(messages.get(0).metricCount).isEqualTo(2);
         assertThat(messages.get(1).metricCount).isEqualTo(1);
@@ -416,7 +426,7 @@ void testTokenShouldBeRedactedInPostFailure() throws Throwable {
         String apiToken = "this.is.a.fake.apiToken";
 
         HttpSender.Request.Builder builder = HttpSender.Request.build("http://localhost", httpClient);
-        // mock the PUT call, so we can even run the post call.
+        // mock the PUT call, so we can even run the post call
         doReturn(builder).when(httpClient).put(anyString());
         doReturn(new HttpSender.Response(200, "")).when(httpClient).send(any(HttpSender.Request.class));
 
@@ -432,7 +442,7 @@ void testTokenShouldBeRedactedInPostFailure() throws Throwable {
                 .extracting(LogEvent::getMessage).containsExactly(
                         // the custom metric was created, meaning the PUT call succeeded
                         "created custom:my.gauge as custom metric in Dynatrace",
-                        // the POST call now threw, and the token is redacted.
+                        // the POST call throws an exception and the token is redacted
                         String.format(
                                 "failed to build request: Illegal character in fragment at index 17: %s/api/v1/entity/infrastructure/custom/?api-token=<redacted>",
                                 invalidUrl));
@@ -459,8 +469,7 @@ void trySendHttpRequestErrorCode() throws Throwable {
         DynatraceExporterV1 exporter = FACTORY.injectLogger(() -> createExporter(httpClient));
         HttpSender.Request.Builder reqBuilder = mock(HttpSender.Request.Builder.class);
 
-        // simulate a failure response. This should be accepted, it will be handled
-        // elsewhere
+        // simulate a failure response, errors are handled elsewhere
         when(reqBuilder.send()).thenReturn(new HttpSender.Response(400, ""));
 
         // test that everything works and no error is logged
@@ -477,9 +486,8 @@ void trySendHttpRequestThrowsAndRedacts() throws Throwable {
 
         HttpSender.Request.Builder reqBuilder = mock(HttpSender.Request.Builder.class);
 
-        // simulate that the request builder throws. This should not happen if the
-        // endpoint is invalid,
-        // as the URI is validated elsewhere.
+        // Simulate that the request builder throws an exception.
+        // Should not happen if the endpoint is invalid, the URI is validated elsewhere.
         String exceptionMessageTemplate = "Exception with the token: %s";
         when(reqBuilder.send()).thenThrow(new Throwable(String.format(exceptionMessageTemplate, apiToken)));