add csvoutput scripting plugin for response curve capture

engine-extensions/src/main/java/io/nosqlbench/engine/extensions/csvoutput/CsvOutput.java

@@ -0,0 +1,4 @@
+package io.nosqlbench.engine.extensions.csvoutput;
+
+public class CsvOutput {
+}

engine-extensions/src/main/java/io/nosqlbench/engine/extensions/csvoutput/CsvOutputPluginData.java

@@ -0,0 +1,22 @@
+package io.nosqlbench.engine.extensions.csvoutput;
+
+import com.codahale.metrics.MetricRegistry;
+import io.nosqlbench.engine.api.extensions.ScriptingPluginInfo;
+import io.nosqlbench.nb.annotations.Service;
+import org.apache.logging.log4j.Logger;
+
+import javax.script.ScriptContext;
+
+@Service(value = ScriptingPluginInfo.class,selector = "csvoutput")
+public class CsvOutputPluginData implements ScriptingPluginInfo<CsvOutputPluginInstance> {
+
+    @Override
+    public String getDescription() {
+        return "Write CSV output to a named file";
+    }
+
+    @Override
+    public CsvOutputPluginInstance getExtensionObject(Logger logger, MetricRegistry metricRegistry, ScriptContext scriptContext) {
+        return new CsvOutputPluginInstance();
+    }
+}

engine-extensions/src/main/java/io/nosqlbench/engine/extensions/csvoutput/CsvOutputPluginInstance.java

@@ -0,0 +1,8 @@
+package io.nosqlbench.engine.extensions.csvoutput;
+
+public class CsvOutputPluginInstance {
+
+    public CsvOutput open(String filename, String... headers) {
+        return new CsvOutputWriter(filename, headers);
+    }
+}

engine-extensions/src/main/java/io/nosqlbench/engine/extensions/csvoutput/CsvOutputWriter.java

@@ -0,0 +1,75 @@
+package io.nosqlbench.engine.extensions.csvoutput;
+
+import org.apache.commons.csv.CSVFormat;
+import org.apache.commons.csv.CSVPrinter;
+import org.graalvm.polyglot.Value;
+
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.*;
+
+public class CsvOutputWriter extends CsvOutput {
+
+    private final CSVPrinter printer;
+    private final FileWriter filewriter;
+    private final LinkedHashSet<String> headerKeys;
+    private final String filename;
+
+    public CsvOutputWriter(String filename, String... headers) {
+        this.filename = filename;
+        CSVFormat fmt = CSVFormat.DEFAULT;
+        this.headerKeys = new LinkedHashSet<>(Arrays.asList(headers));
+        try {
+            this.filewriter = new FileWriter(filename);
+            this.printer = new CSVPrinter(filewriter,fmt);
+            if (Files.size(Path.of(filename))==0) {
+                printer.printRecord(headerKeys);
+                printer.flush();
+            }
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public CsvOutputWriter write(Value value) {
+        List<String> lineout = new ArrayList<>();
+        Map<String,String> provided = new HashMap<>();
+        if (value.isHostObject()) {
+            Object o = value.asHostObject();
+            if (o instanceof Map) {
+                ((Map<?, ?>) o).forEach((k,v) -> {
+                    provided.put(k.toString(),v.toString());
+                });
+            } else {
+                throw new RuntimeException("host object provided as '" + o.getClass().getCanonicalName()+ ", but only Maps are supported.");
+            }
+        } else if (value.hasMembers()) {
+            for (String vkey : value.getMemberKeys()) {
+                provided.put(vkey,value.getMember(vkey).toString());
+            }
+        } else {
+            throw new RuntimeException("Value was not a Map host object nor a type with members.");
+        }
+
+        for (String headerKey : headerKeys) {
+            if (provided.containsKey(headerKey)) {
+                lineout.add(provided.remove(headerKey));
+            } else {
+                lineout.add("");
+            }
+        }
+        if (provided.size()>0) {
+            throw new RuntimeException("Unqualified column was emitted for file '" + filename);
+        }
+
+        try {
+            printer.printRecord(lineout);
+            printer.flush();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+        return this;
+    }
+}

engine-extensions/src/main/java/io/nosqlbench/engine/extensions/csvoutput/csvoutput.md

@@ -0,0 +1,13 @@
+csvoutput extension
+===================
+
+This extension makes it easy to start writing CSV data to a file,
+using a defined set of headers.
+
+### Examples
+
+Open a writer and write a row:
+
+    var out=csvoutput.open('output.csv','time','value');
+    out.write({'time':23,'value':23});
+

engine-extensions/src/test/java/io/nosqlbench/engine/extensions/csvoutput/CsvOutputWriterTest.java

@@ -0,0 +1,22 @@
+package io.nosqlbench.engine.extensions.csvoutput;
+
+import org.assertj.core.util.Files;
+import org.graalvm.polyglot.Value;
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+import java.util.Map;
+
+public class CsvOutputWriterTest {
+
+    @Test
+    public void testCsvOutputWriter() {
+        File tmpfile = Files.newTemporaryFile();
+        tmpfile.deleteOnExit();
+        System.out.println("tmpfile="+ tmpfile.getPath());
+        CsvOutputWriter out = new CsvOutputWriter(tmpfile.getPath(), "one", "two");
+        out.write(Value.asValue(Map.of("one","one_","two","two_")));
+    }
+
+
+}

nb/src/test/java/io/nosqlbench/engine/core/script/AsyncScriptIntegrationTests.java

@@ -178,6 +178,16 @@ public class AsyncScriptIntegrationTests {
         assertThat(logdata.split("Tag=testhistostatslogger.cycles.servicetime,").length).isGreaterThanOrEqualTo(2);
     }
 
+    @Test
+    public void testExtensionCsvOutput() throws IOException {
+        ScenarioResult scenarioResult = runScenario("extension_csvoutput");
+        List<String> strings = Files.readAllLines(Paths.get(
+            "logs/csvoutputtestfile.csv"));
+        String logdata = strings.stream().collect(Collectors.joining("\n"));
+        assertThat(logdata).contains("header1,header2");
+        assertThat(logdata).contains("value1,value2");
+    }
+
     @Test
     public void testExtensionHistogramLogger() throws IOException {
         ScenarioResult scenarioResult = runScenario("extension_histologger");

nb/src/test/resources/scripts/async/extension_csvoutput.js

@@ -0,0 +1,20 @@
+/*
+ *
+ *    Copyright 2016 jshook
+ *    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.
+ * /
+ */
+
+var csvlogger = csvoutput.open("logs/csvoutputtestfile.csv","header1","header2");
+
+csvlogger.write({"header1": "value1","header2":"value2"});