Added configConverter which converts conf to yaml

Signed-off-by: Asif Sohail Mohammed <[email protected]>

data-prepper-logstash-configuration/src/main/java/org/opensearch/dataprepper/logstash/parser/LogstashConfigConverter.java

@@ -0,0 +1,56 @@
+package org.opensearch.dataprepper.logstash.parser;
+
+import com.amazon.dataprepper.model.configuration.PipelineModel;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
+import com.fasterxml.jackson.dataformat.yaml.YAMLGenerator;
+import org.antlr.v4.runtime.CharStreams;
+import org.antlr.v4.runtime.CommonTokenStream;
+import org.antlr.v4.runtime.tree.ParseTree;
+import org.opensearch.dataprepper.logstash.LogstashLexer;
+import org.opensearch.dataprepper.logstash.LogstashParser;
+import org.opensearch.dataprepper.logstash.mapping.LogstashMapper;
+import org.opensearch.dataprepper.logstash.model.LogstashConfiguration;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Collections;
+import java.util.Map;
+
+/**
+ * Converts Logstash configuration file and returns YAML file location
+ *
+ * @since 1.2
+ */
+public class LogstashConfigConverter {
+    public String convertLogstashConfigurationToPipeline(String logstashConfigurationPath, String outputDirectory) throws IOException {
+        final String logstashConfigAsString = new String(Files.readAllBytes(Paths.get(logstashConfigurationPath)));
+
+        LogstashLexer lexer = new LogstashLexer(CharStreams.fromString(logstashConfigAsString));
+        CommonTokenStream tokens = new CommonTokenStream(lexer);
+        LogstashParser parser = new LogstashParser(tokens);
+        ParseTree tree = parser.config();
+
+        LogstashVisitor visitor = new LogstashVisitor();
+        LogstashConfiguration logstashConfiguration = (LogstashConfiguration) visitor.visit(tree);
+
+        LogstashMapper logstashMapper = new LogstashMapper();
+        PipelineModel pipelineModel = logstashMapper.mapPipeline(logstashConfiguration);
+        Map<String, Object> pipeline = Collections.singletonMap("log-pipeline", pipelineModel);
+
+        YAMLFactory factory = new YAMLFactory();
+        factory.disable(YAMLGenerator.Feature.WRITE_DOC_START_MARKER);
+        factory.enable(YAMLGenerator.Feature.INDENT_ARRAYS_WITH_INDICATOR);
+        factory.disable(YAMLGenerator.Feature.SPLIT_LINES);
+        factory.enable(YAMLGenerator.Feature.LITERAL_BLOCK_STYLE);
+
+        ObjectMapper mapper = new ObjectMapper(factory);
+
+        String yamlFilePath = outputDirectory + "logstash.yaml";
+        mapper.writeValue(new File(yamlFilePath), pipeline);
+
+        return yamlFilePath;
+    }
+}

data-prepper-logstash-configuration/src/test/java/org/opensearch/dataprepper/logstash/parser/LogstashConfigConverterTest.java

@@ -0,0 +1,29 @@
+package org.opensearch.dataprepper.logstash.parser;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import java.io.IOException;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+
+class LogstashConfigConverterTest {
+    private LogstashConfigConverter logstashConfigConverter;
+
+    @BeforeEach
+    void createObjectUnderTest() {
+        logstashConfigConverter = new LogstashConfigConverter();
+    }
+
+    @Test
+    void convertLogstashConfigurationToPipeline() throws IOException {
+
+        String outputDirectory = "build/resources/test/org/opensearch/dataprepper/logstash/parser/";
+        String confPath = "src/test/resources/org/opensearch/dataprepper/logstash/parser/logstash.conf";
+
+        String actualYamlPath =  logstashConfigConverter.convertLogstashConfigurationToPipeline(confPath, outputDirectory);
+        String expectedYamlPath = "build/resources/test/org/opensearch/dataprepper/logstash/parser/logstash.yaml";
+
+        assertThat(actualYamlPath, equalTo(expectedYamlPath));
+    }
+}

data-prepper-logstash-configuration/src/test/resources/org/opensearch/dataprepper/logstash/parser/logstash.conf

@@ -0,0 +1,14 @@
+input {
+    http {
+        port => 8000
+        threads => 100
+        max_pending_requests => 128
+    }
+}
+output {
+    elasticsearch {
+        hosts => ["https://localhost:9200"]
+        user => admin
+        password => admin
+    }
+}