Start MigrateEmptyLabelMiskCounter

src/main/java/org/openrewrite/micrometer/misk/MigrateEmptyLabelMiskCounter.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2023 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * https://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.
+ */
+package org.openrewrite.micrometer.misk;
+
+import io.micrometer.core.instrument.Counter;
+import io.micrometer.core.instrument.Metrics;
+import org.openrewrite.*;
+import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.MethodMatcher;
+import org.openrewrite.java.search.UsesType;
+import org.openrewrite.java.template.Semantics;
+import org.openrewrite.java.tree.J;
+
+import java.util.List;
+
+import static kotlin.collections.CollectionsKt.listOf;
+import static org.openrewrite.java.template.Semantics.expression;
+
+public class MigrateEmptyLabelMiskCounter extends Recipe {
+
+    @Override
+    public String getDisplayName() {
+        return "Migrate Misk counter to Micrometer";
+    }
+
+    @Override
+    public String getDescription() {
+        return "Convert a Misk (Prometheus) counter to a Micrometer counter.";
+    }
+
+    @Override
+    public List<Recipe> getRecipeList() {
+        return super.getRecipeList();
+    }
+
+    @Override
+    public TreeVisitor<?, ExecutionContext> getVisitor() {
+        return Preconditions.check(new UsesType<>("misk.metrics.v2.Metrics", true), new JavaIsoVisitor<>() {
+            final MethodMatcher miskCounter = new MethodMatcher("misk.metrics.v2.Metrics counter(..)");
+
+            @Override
+            public J.MethodInvocation visitMethodInvocation(J.MethodInvocation method, ExecutionContext ctx) {
+                J.MethodInvocation m = super.visitMethodInvocation(method, ctx);
+                if (miskCounter.matches(method)) {
+                    boolean emptyLabel = method.getArguments().size() == 2;
+                    if (method.getArguments().size() == 3) {
+                        emptyLabel = expression(this, "listOf", () -> listOf()).build()
+                                .matches(new Cursor(getCursor(), method.getArguments().get(2)));
+                    }
+                    if (!emptyLabel) {
+                        return m;
+                    }
+                    m = expression(
+                            this, "micrometerCounter",
+                            (String name, String help) -> Counter.builder(name).description(help).register(Metrics.globalRegistry)
+                    ).build().apply(getCursor(),
+                            method.getCoordinates().replace(),
+                            method.getArguments().get(0),
+                            method.getArguments().get(1));
+
+                    maybeRemoveImport("misk.metrics.v2.Metrics");
+                }
+                return m;
+            }
+        });
+    }
+}

src/main/java/org/openrewrite/micrometer/misk/NoExplicitEmptyLabelList.java

@@ -1,3 +1,18 @@
+/*
+ * Copyright 2023 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * https://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.
+ */
 package org.openrewrite.micrometer.misk;
 
 import misk.metrics.v2.Metrics;

src/main/resources/META-INF/rewrite/misk.yml

@@ -0,0 +1,23 @@
+#
+# Copyright 2023 the original author or authors.
+# <p>
+# 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
+# <p>
+# https://www.apache.org/licenses/LICENSE-2.0
+# <p>
+# 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.
+#
+---
+type: specs.openrewrite.org/v1beta/recipe
+name: org.openrewrite.micrometer.misk.MigrateMiskToMicrometer
+displayName: Migrate Misk metrics to Micrometer
+description: This recipe will move Misk metrics to Micrometer, where that is possible to do without a loss of fidelity.
+recipeList:
+  - org.openrewrite.micrometer.misk.NoExplicitEmptyLabelList
+  - org.openrewrite.micrometer.misk.MigrateEmptyLabelMiskCounter

src/test/java/org/openrewrite/micrometer/misk/MigrateEmptyLabelMiskCounterTest.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2023 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * https://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.
+ */
+package org.openrewrite.micrometer.misk;
+
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.test.RecipeSpec;
+import org.openrewrite.test.RewriteTest;
+
+import static org.openrewrite.java.Assertions.java;
+
+public class MigrateEmptyLabelMiskCounterTest implements RewriteTest {
+
+    @Override
+    public void defaults(RecipeSpec spec) {
+        spec.recipe(new MigrateEmptyLabelMiskCounter())
+          .parser(JavaParser.fromJavaVersion()
+            .classpath("misk-metrics", "kotlin-reflect", "kotlin-stdlib"));
+    }
+
+    @Disabled
+    @Test
+    void migrateEmptyLabel() {
+        //language=java
+        rewriteRun(
+          java(
+            """
+              import misk.metrics.v2.Metrics;
+              import static kotlin.collections.CollectionsKt.listOf;
+                            
+              class Test {
+                void test(Metrics metrics) {
+                    metrics.counter("counter", "description", listOf());
+                }
+              }
+              """,
+            """
+              import io.micrometer.core.instrument.Counter;
+              
+              import static kotlin.collections.CollectionsKt.listOf;
+                            
+              class Test {
+                void test(Metrics metrics) {
+                    Counter.builder("counter").description("description").register(Metrics.globalRegistry);
+                }
+              }
+              """
+          )
+        );
+    }
+}

src/test/java/org/openrewrite/micrometer/misk/NoExplicitEmptyLabelListTest.java

@@ -1,3 +1,18 @@
+/*
+ * Copyright 2023 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * https://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.
+ */
 package org.openrewrite.micrometer.misk;
 
 import org.junit.jupiter.api.Disabled;