exceptionfactory commented on code in PR #10214: URL: https://github.com/apache/nifi/pull/10214#discussion_r2290987788
########## nifi-extension-bundles/nifi-protobuf-bundle/nifi-protobuf-services/src/main/java/org/apache/nifi/services/protobuf/ProtobufSchemaCompiler.java: ########## @@ -0,0 +1,283 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You 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.apache.nifi.services.protobuf; + +import com.github.benmanes.caffeine.cache.Cache; +import com.github.benmanes.caffeine.cache.Caffeine; +import com.squareup.wire.schema.CoreLoaderKt; +import com.squareup.wire.schema.Location; +import com.squareup.wire.schema.Schema; +import com.squareup.wire.schema.SchemaLoader; +import org.apache.commons.io.FileUtils; +import org.apache.nifi.logging.ComponentLog; +import org.apache.nifi.schemaregistry.services.SchemaDefinition; +import org.apache.nifi.serialization.record.SchemaIdentifier; + +import java.io.IOException; +import java.nio.file.FileSystems; +import java.nio.file.Files; +import java.nio.file.Path; +import java.nio.file.StandardOpenOption; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Collections; +import java.util.List; +import java.util.Map; +import java.util.concurrent.TimeUnit; + +/** + * Handles Protocol Buffer schema compilation, caching, and temporary directory operations. + * This class is responsible for compiling schema definitions into Wire Schema objects, + * managing a cache of compiled schemas, and handling temporary directory operations + * required during the compilation process. + */ +final class ProtobufSchemaCompiler { + + private static final List<Location> STANDARD_PROTOBUF_LOCATIONS = Arrays.asList( + Location.get(CoreLoaderKt.WIRE_RUNTIME_JAR, "google/protobuf/any.proto"), + Location.get(CoreLoaderKt.WIRE_RUNTIME_JAR, "google/protobuf/duration.proto"), + Location.get(CoreLoaderKt.WIRE_RUNTIME_JAR, "google/protobuf/empty.proto"), + Location.get(CoreLoaderKt.WIRE_RUNTIME_JAR, "google/protobuf/struct.proto"), + Location.get(CoreLoaderKt.WIRE_RUNTIME_JAR, "google/protobuf/timestamp.proto"), + Location.get(CoreLoaderKt.WIRE_RUNTIME_JAR, "google/protobuf/wrappers.proto") + ); + private static final int CACHE_EXPIRE_HOURS = 1; + private static final int COMPILED_SCHEMAS_CACHE_SIZE = 200; + + private final Cache<SchemaIdentifier, Schema> compiledSchemaCache; + private final ComponentLog logger; + + /** + * Creates a new ProtobufSchemaCompiler with default cache settings. + * + * @param logger the component logger for logging compilation activities + */ + public ProtobufSchemaCompiler(final ComponentLog logger) { + this.logger = logger; + this.compiledSchemaCache = Caffeine.newBuilder() + .expireAfterAccess(CACHE_EXPIRE_HOURS, TimeUnit.HOURS) + .maximumSize(COMPILED_SCHEMAS_CACHE_SIZE) + .build(); + } + + /** + * Compiles a schema definition or retrieves it from cache. + * + * @param schemaDefinition the schema definition to compile + * @return the compiled Schema + */ + public Schema compileOrGetFromCache(final SchemaDefinition schemaDefinition) { + return compiledSchemaCache.get(schemaDefinition.getIdentifier(), + identifier -> { + try { + return compileSchemaDefinition(schemaDefinition); + } catch (final IOException e) { + throw new RuntimeException("Could not compile schema for identifier: " + identifier, e); + } + }); + } + + /** + * Invalidates all cached schemas. + */ + public void invalidateCache() { + if (compiledSchemaCache != null) { + compiledSchemaCache.invalidateAll(); + } + } + + /** + * Compiles a SchemaDefinition structure into a Schema using the wire library. + * Creates a temporary directory structure that mirrors the package structure and + * places all schemas in their appropriate directories. + * + * @param schemaDefinition the main schema definition to compile + * @return the compiled Schema + * @throws IOException if unable to create temporary files or compile schema + */ + private Schema compileSchemaDefinition(final SchemaDefinition schemaDefinition) throws IOException { + logger.debug("Starting schema compilation for identifier: {}", schemaDefinition.getIdentifier()); + + // Validate that all schema identifiers end with .proto extension + validateSchemaDefinitionIdentifiers(schemaDefinition, true); + + return executeWithTemporaryDirectory(tempDir -> { + try { + // Process main schema definition + writeSchemaToTempDirectory(tempDir, schemaDefinition); + + // Process all referenced schemas recursively + processSchemaReferences(tempDir, schemaDefinition.getReferences()); + + // Create and configure schema loader + final Schema compiledSchema = createAndLoadSchema(tempDir); + logger.debug("Successfully compiled schema for identifier: {}", schemaDefinition.getIdentifier()); + return compiledSchema; + + } catch (final Exception e) { + throw new RuntimeException("Failed to compile Protobuf schema for identifier: " + schemaDefinition.getIdentifier(), e); + } + }); + } + + /** + * Executes a function with a temporary directory, ensuring proper cleanup. + * + * @param function the function to execute with the temporary directory + * @return the result of the function + * @throws IOException if unable to create or manage temporary directory + */ + private <T> T executeWithTemporaryDirectory(final WithTemporaryDirectory<T> function) throws IOException { + final Path tempDir = Files.createTempDirectory("nifi-protobuf-schema"); Review Comment: Thanks for the background. I agree that an in-memory `FileSystem` introduces dependency concerns, and a custom implementation of the `Loader` interface would be very involved. With that, I would just change the temporary directory name to use the Component Identifier of the calling Controller Service. This can be passed to the constructor, along with the `ComponentLog`, and would provide a way to associate the directory to the particular component instance. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
