1 files changed, 92 insertions, 0 deletions
diff --git a/build/hv-collector-analysis/src/main/kotlin/org/onap/dcae/collectors/veshv/analysis/SuboptimalLoggerUsage.kt b/build/hv-collector-analysis/src/main/kotlin/org/onap/dcae/collectors/veshv/analysis/SuboptimalLoggerUsage.kt
new file mode 100644
index 00000000..a070584c
--- /dev/null
+++ b/build/hv-collector-analysis/src/main/kotlin/org/onap/dcae/collectors/veshv/analysis/SuboptimalLoggerUsage.kt
@@ -0,0 +1,92 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.analysis
+
+import io.gitlab.arturbosch.detekt.api.CodeSmell
+import io.gitlab.arturbosch.detekt.api.Config
+import io.gitlab.arturbosch.detekt.api.Debt
+import io.gitlab.arturbosch.detekt.api.Entity
+import io.gitlab.arturbosch.detekt.api.Issue
+import io.gitlab.arturbosch.detekt.api.Rule
+import io.gitlab.arturbosch.detekt.api.Severity
+import org.jetbrains.kotlin.com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.psi.KtCallExpression
+import org.jetbrains.kotlin.psi.KtOperationExpression
+import org.jetbrains.kotlin.psi.KtStringTemplateExpression
+import org.jetbrains.kotlin.psi.KtValueArgumentList
+import org.jetbrains.kotlin.psi.psiUtil.anyDescendantOfType
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since November 2018
+ */
+class SuboptimalLoggerUsage(config: Config) : Rule(config) {
+
+    override val issue = Issue(javaClass.simpleName,
+            Severity.Performance,
+            """
+                Reports usage of unoptimized logger calls.
+                In Kotlin every method call (including logger calls) is eagerly evaluated by default. That means that
+                each argument will be evaluated even if loglevel is higher than in current call. The most common way of
+                mitigating this issue is to use lazy loading by means of lambda expressions, so instead of
+                log.debug("a=${'$'}a") we can write log.debug{ "a=${'$'}a" }. Logging string literals is fine - no
+                additional computation will be performed.""".trimIndent(),
+            Debt(mins = 10))
+
+    private val loggerNames = config.valueOrDefault("loggerNames", DEFAULT_LOGGER_NAMES).split(",")
+
+    private val loggingMethods = config.valueOrDefault("loggingMethodNames", DEFAULT_LOGGING_METHOD_NAMES).split(",")
+
+    override fun visitCallExpression(expression: KtCallExpression) {
+        val targetObject = expression.parent.firstChild
+        val methodName = expression.firstChild
+
+        logExpressionArguments(targetObject, methodName)
+                ?.let(this::checkGettingWarningMessage)
+                ?.let { reportCodeSmell(expression, it) }
+    }
+
+    private fun logExpressionArguments(targetObject: PsiElement, methodName: PsiElement) =
+            if (isLogExpression(targetObject, methodName))
+                methodName.nextSibling as? KtValueArgumentList
+            else null
+
+    private fun isLogExpression(targetObject: PsiElement, methodName: PsiElement) =
+            loggerNames.any(targetObject::textMatches) && loggingMethods.any(methodName::textMatches)
+
+    private fun checkGettingWarningMessage(args: KtValueArgumentList) = when {
+        args.anyDescendantOfType<KtOperationExpression> { true } ->
+            "should not use any operators in logging expression"
+        args.anyDescendantOfType<KtCallExpression> { true } ->
+            "should not call anything in logging expression"
+        args.anyDescendantOfType<KtStringTemplateExpression> { it.hasInterpolation() } ->
+            "should not use string interpolation in logging expression"
+        else -> null
+    }
+
+    private fun reportCodeSmell(expression: KtCallExpression, message: String) {
+        report(CodeSmell(issue, Entity.from(expression), message))
+    }
+
+    companion object {
+        const val DEFAULT_LOGGER_NAMES = "logger,LOGGER,log,LOG"
+        const val DEFAULT_LOGGING_METHOD_NAMES = "trace,debug,info,warn,error,severe"
+    }
+}