Check iKey length for live metrics iKey masking (Azure#44323)

Author: jeanbisutti

sdk/monitor/azure-monitor-opentelemetry-autoconfigure/checkstyle-suppressions.xml

@@ -271,6 +271,8 @@
   <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.CpuPerformanceCounterCalculator.java" checks="MissingJavadocTypeCheck" />
   <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.FormattedDuration.java" checks="MissingJavadocTypeCheck" />
   <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.FormattedTime.java" checks="MissingJavadocTypeCheck" />
+  <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.IKeyMasker.java" checks="MissingJavadocTypeCheck" />
+  <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.IKeyMasker.java" checks="MissingJavadocMethodCheck" />
   <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.HostName.java" checks="MissingJavadocTypeCheck" />
   <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.ResourceParser.java" checks="MissingJavadocTypeCheck" />
   <suppress files="com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.StatusCode.java" checks="MissingJavadocTypeCheck" />

sdk/monitor/azure-monitor-opentelemetry-autoconfigure/src/main/java/com/azure/monitor/opentelemetry/autoconfigure/implementation/pipeline/TelemetryItemExporter.java

@@ -12,6 +12,7 @@
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.models.ContextTagKeys;
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.models.TelemetryItem;
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.AksResourceAttributes;
+import com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.IKeyMasker;
 import io.opentelemetry.sdk.common.CompletableResultCode;
 import io.opentelemetry.sdk.resources.Resource;
 import io.opentelemetry.semconv.ServiceAttributes;
@@ -167,14 +168,8 @@ private static String toJson(List<TelemetryItem> telemetryItems) throws IOExcept
     private static String maskIKeys(List<TelemetryItem> telemetryItems, String json) {
         Set<String> iKeys
             = telemetryItems.stream().map(TelemetryItem::getInstrumentationKey).collect(Collectors.toSet());
-        int charactersToKeepAtEnd = 13;
         for (String instrumentationKey : iKeys) {
-            // Tests could set  the connection string with a short one
-            if (instrumentationKey.length() > charactersToKeepAtEnd) {
-                String maskedIKey
-                    = "*" + instrumentationKey.substring(instrumentationKey.length() - charactersToKeepAtEnd);
-                json = json.replace(instrumentationKey, maskedIKey);
-            }
+            json = json.replace(instrumentationKey, IKeyMasker.mask(instrumentationKey));
         }
         return json;
     }

sdk/monitor/azure-monitor-opentelemetry-autoconfigure/src/main/java/com/azure/monitor/opentelemetry/autoconfigure/implementation/quickpulse/QuickPulse.java

@@ -12,6 +12,7 @@
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.quickpulse.swagger.LiveMetricsRestAPIsForClientSDKsBuilder;
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.quickpulse.swagger.models.MonitoringDataPoint;
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.HostName;
+import com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.IKeyMasker;
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.Strings;
 import com.azure.monitor.opentelemetry.autoconfigure.implementation.utils.ThreadPoolUtils;
 import reactor.util.annotation.Nullable;
@@ -76,7 +77,8 @@ private void initialize(HttpPipeline httpPipeline, Supplier<URL> endpointUrl, Su
         if (LOGGER.canLogAtLevel(LogLevel.VERBOSE)) {
             LOGGER.verbose(
                 "Initializing QuickPulse with instrumentation key: {} , URL {}, rolename {}, role instance {}, sdk version {}",
-                maskIkey(instrumentationKey.get()), endpointUrl.get().toString(), roleName, roleInstance, sdkVersion);
+                IKeyMasker.mask(instrumentationKey.get()), endpointUrl.get().toString(), roleName, roleInstance,
+                sdkVersion);
         }
 
         String quickPulseId = UUID.randomUUID().toString().replace("-", "");
@@ -131,7 +133,4 @@ private void initialize(HttpPipeline httpPipeline, Supplier<URL> endpointUrl, Su
         this.collector = collector;
     }
 
-    private String maskIkey(String ikey) {
-        return "*" + ikey.substring(ikey.length() - 13);
-    }
 }

sdk/monitor/azure-monitor-opentelemetry-autoconfigure/src/main/java/com/azure/monitor/opentelemetry/autoconfigure/implementation/utils/IKeyMasker.java

@@ -0,0 +1,20 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.azure.monitor.opentelemetry.autoconfigure.implementation.utils;
+
+public final class IKeyMasker {
+
+    private static final int CHARACTERS_TO_KEEP_AT_END = 13;
+
+    private IKeyMasker() {
+    }
+
+    public static String mask(String instrumentationKey) {
+        // Tests could set the connection string with a short one
+        if (instrumentationKey.length() > CHARACTERS_TO_KEEP_AT_END) {
+            return "*" + instrumentationKey.substring(instrumentationKey.length() - CHARACTERS_TO_KEEP_AT_END);
+        }
+        return instrumentationKey;
+    }
+}