Common code for generating schema file names (#267)

* Common code for generating schema file names

type/build.gradle.kts

@@ -22,8 +22,7 @@ val spotBugsVersion : String by extra
 
 dependencies {
     api(project(":annotation"))
-
-    implementation("com.github.spotbugs:spotbugs-annotations:$spotBugsVersion")
+    api("com.github.spotbugs:spotbugs-annotations:$spotBugsVersion")
 
     // Do not add any other non-test runtime dependencies
 }

type/src/main/java/module-info.java

@@ -1,10 +1,11 @@
 /** Module containing types used by many other Creek modules */
 module creek.base.type {
     requires transitive creek.base.annotation;
-    requires com.github.spotbugs.annotations;
+    requires transitive com.github.spotbugs.annotations;
 
     exports org.creekservice.api.base.type;
     exports org.creekservice.api.base.type.config;
-    exports org.creekservice.api.base.type.temporal;
     exports org.creekservice.api.base.type.json;
+    exports org.creekservice.api.base.type.temporal;
+    exports org.creekservice.api.base.type.schema;
 }

type/src/main/java/org/creekservice/api/base/type/schema/GeneratedSchemas.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2024 Creek Contributors (https://github.com/creek-service)
+ *
+ * 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.
+ */
+
+package org.creekservice.api.base.type.schema;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+/**
+ * Utility class for working with {@link
+ * org.creekservice.api.base.annotation.schema.GeneratesSchema} types.
+ */
+public final class GeneratedSchemas {
+
+    private GeneratedSchemas() {}
+
+    /**
+     * The schema filename for a given type.
+     *
+     * @param type the type
+     * @param extension the expected file extension, e.g. {@code ".yml"}.
+     * @return the filename the schema will be stored in.
+     */
+    @SuppressFBWarnings(value = "PATH_TRAVERSAL_IN", justification = "False positive")
+    public static Path schemaFileName(final Class<?> type, final String extension) {
+        final String name =
+                type.getName()
+                        .replaceAll("([A-Z])", "_$1")
+                        .replaceFirst("_", "")
+                        .replaceAll("\\$_", "\\$")
+                        .toLowerCase();
+
+        return Paths.get(name + extension);
+    }
+
+    /**
+     * @return the file extension used for YAML files.
+     */
+    public static String yamlExtension() {
+        return ".yml";
+    }
+}

type/src/test/java/org/creekservice/api/base/type/schema/GeneratedSchemasTest.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2024 Creek Contributors (https://github.com/creek-service)
+ *
+ * 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.
+ */
+
+package org.creekservice.api.base.type.schema;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
+import java.nio.file.Path;
+import org.junit.jupiter.api.Test;
+
+class GeneratedSchemasTest {
+
+    @Test
+    void shouldGenerateFileName() {
+        assertThat(
+                GeneratedSchemas.schemaFileName(
+                        GeneratedSchemasTest.class, GeneratedSchemas.yamlExtension()),
+                is(Path.of("org.creekservice.api.base.type.schema.generated_schemas_test.yml")));
+    }
+
+    @Test
+    void shouldWriteSchemaForNestedType() {
+        assertThat(
+                GeneratedSchemas.schemaFileName(Nested.class, GeneratedSchemas.yamlExtension()),
+                is(
+                        Path.of(
+                                "org.creekservice.api.base.type.schema.generated_schemas_test$nested.yml")));
+    }
+
+    @Test
+    void shouldWriteSchemaForLocalType() {
+        // Given:
+        final class Model {}
+
+        // Then:
+        assertThat(
+                GeneratedSchemas.schemaFileName(Model.class, GeneratedSchemas.yamlExtension()),
+                is(
+                        Path.of(
+                                "org.creekservice.api.base.type.schema.generated_schemas_test$1_model.yml")));
+    }
+
+    private static final class Nested {}
+}