Add JSON pretty-print support to logging-otlp exporters

Closes #5972

Author: lucacavenaghi97

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/OtlpJsonLoggingLogRecordExporter.java

@@ -29,7 +29,10 @@ public final class OtlpJsonLoggingLogRecordExporter implements LogRecordExporter
   /** Returns a new {@link OtlpJsonLoggingLogRecordExporter}. */
   public static LogRecordExporter create() {
     OtlpStdoutLogRecordExporter delegate =
-        new OtlpStdoutLogRecordExporterBuilder(logger).setWrapperJsonObject(false).build();
+        new OtlpStdoutLogRecordExporterBuilder(logger)
+            .setWrapperJsonObject(false)
+            .setPrettyPrint(true)
+            .build();
     return new OtlpJsonLoggingLogRecordExporter(delegate);
   }
 

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/OtlpJsonLoggingMetricExporter.java

@@ -42,7 +42,10 @@ public static MetricExporter create() {
    */
   public static MetricExporter create(AggregationTemporality aggregationTemporality) {
     OtlpStdoutMetricExporter delegate =
-        new OtlpStdoutMetricExporterBuilder(logger).setWrapperJsonObject(false).build();
+        new OtlpStdoutMetricExporterBuilder(logger)
+            .setWrapperJsonObject(false)
+            .setPrettyPrint(true)
+            .build();
     return new OtlpJsonLoggingMetricExporter(delegate, aggregationTemporality);
   }
 

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/OtlpJsonLoggingSpanExporter.java

@@ -27,7 +27,10 @@ public final class OtlpJsonLoggingSpanExporter implements SpanExporter {
   /** Returns a new {@link OtlpJsonLoggingSpanExporter}. */
   public static SpanExporter create() {
     OtlpStdoutSpanExporter delegate =
-        new OtlpStdoutSpanExporterBuilder(logger).setWrapperJsonObject(false).build();
+        new OtlpStdoutSpanExporterBuilder(logger)
+            .setWrapperJsonObject(false)
+            .setPrettyPrint(true)
+            .build();
     return new OtlpJsonLoggingSpanExporter(delegate);
   }
 

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/internal/logs/OtlpStdoutLogRecordExporterBuilder.java

@@ -14,6 +14,7 @@
 import io.opentelemetry.sdk.common.export.MemoryMode;
 import java.io.OutputStream;
 import java.util.logging.Logger;
+import javax.annotation.Nullable;
 
 /**
  * Builder for {@link OtlpJsonLoggingLogRecordExporter}.
@@ -26,13 +27,14 @@ public final class OtlpStdoutLogRecordExporterBuilder {
   private static final String TYPE = "log records";
 
   private final Logger logger;
-  private JsonWriter jsonWriter;
+  @Nullable private OutputStream outputStream;
+  @Nullable private Logger outputLogger;
   private boolean wrapperJsonObject = true;
   private MemoryMode memoryMode = MemoryMode.IMMUTABLE_DATA;
+  private boolean prettyPrint;
 
   public OtlpStdoutLogRecordExporterBuilder(Logger logger) {
     this.logger = logger;
-    this.jsonWriter = new LoggerJsonWriter(logger, TYPE);
   }
 
   /**
@@ -57,6 +59,12 @@ public OtlpStdoutLogRecordExporterBuilder setMemoryMode(MemoryMode memoryMode) {
     return this;
   }
 
+  /** Sets the exporter to use pretty-printed JSON output. */
+  public OtlpStdoutLogRecordExporterBuilder setPrettyPrint(boolean prettyPrint) {
+    this.prettyPrint = prettyPrint;
+    return this;
+  }
+
   /**
    * Sets the exporter to use the specified output stream.
    *
@@ -67,14 +75,16 @@ public OtlpStdoutLogRecordExporterBuilder setMemoryMode(MemoryMode memoryMode) {
    */
   public OtlpStdoutLogRecordExporterBuilder setOutput(OutputStream outputStream) {
     requireNonNull(outputStream, "outputStream");
-    this.jsonWriter = new StreamJsonWriter(outputStream, TYPE);
+    this.outputStream = outputStream;
+    this.outputLogger = null;
     return this;
   }
 
   /** Sets the exporter to use the specified logger. */
   public OtlpStdoutLogRecordExporterBuilder setOutput(Logger logger) {
     requireNonNull(logger, "logger");
-    this.jsonWriter = new LoggerJsonWriter(logger, TYPE);
+    this.outputLogger = logger;
+    this.outputStream = null;
     return this;
   }
 
@@ -88,6 +98,13 @@ public OtlpStdoutLogRecordExporter build() {
       throw new IllegalArgumentException(
           "Reusable data mode is not supported without wrapperJsonObject");
     }
+    JsonWriter jsonWriter;
+    if (outputStream != null) {
+      jsonWriter = new StreamJsonWriter(outputStream, TYPE, prettyPrint);
+    } else {
+      Logger writerLogger = outputLogger != null ? outputLogger : this.logger;
+      jsonWriter = new LoggerJsonWriter(writerLogger, TYPE, prettyPrint);
+    }
     return new OtlpStdoutLogRecordExporter(logger, jsonWriter, wrapperJsonObject, memoryMode);
   }
 }

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/internal/metrics/OtlpStdoutMetricExporterBuilder.java

@@ -18,6 +18,7 @@
 import io.opentelemetry.sdk.metrics.export.MetricExporter;
 import java.io.OutputStream;
 import java.util.logging.Logger;
+import javax.annotation.Nullable;
 
 /**
  * Builder for {@link OtlpJsonLoggingMetricExporter}.
@@ -39,13 +40,14 @@ public final class OtlpStdoutMetricExporterBuilder {
       DefaultAggregationSelector.getDefault();
 
   private final Logger logger;
-  private JsonWriter jsonWriter;
+  @Nullable private OutputStream outputStream;
+  @Nullable private Logger outputLogger;
   private boolean wrapperJsonObject = true;
   private MemoryMode memoryMode = MemoryMode.IMMUTABLE_DATA;
+  private boolean prettyPrint;
 
   public OtlpStdoutMetricExporterBuilder(Logger logger) {
     this.logger = logger;
-    this.jsonWriter = new LoggerJsonWriter(logger, TYPE);
   }
 
   /**
@@ -70,6 +72,12 @@ public OtlpStdoutMetricExporterBuilder setMemoryMode(MemoryMode memoryMode) {
     return this;
   }
 
+  /** Sets the exporter to use pretty-printed JSON output. */
+  public OtlpStdoutMetricExporterBuilder setPrettyPrint(boolean prettyPrint) {
+    this.prettyPrint = prettyPrint;
+    return this;
+  }
+
   /**
    * Sets the exporter to use the specified output stream.
    *
@@ -80,14 +88,16 @@ public OtlpStdoutMetricExporterBuilder setMemoryMode(MemoryMode memoryMode) {
    */
   public OtlpStdoutMetricExporterBuilder setOutput(OutputStream outputStream) {
     requireNonNull(outputStream, "outputStream");
-    this.jsonWriter = new StreamJsonWriter(outputStream, TYPE);
+    this.outputStream = outputStream;
+    this.outputLogger = null;
     return this;
   }
 
   /** Sets the exporter to use the specified logger. */
   public OtlpStdoutMetricExporterBuilder setOutput(Logger logger) {
     requireNonNull(logger, "logger");
-    this.jsonWriter = new LoggerJsonWriter(logger, TYPE);
+    this.outputLogger = logger;
+    this.outputStream = null;
     return this;
   }
 
@@ -131,6 +141,13 @@ public OtlpStdoutMetricExporter build() {
       throw new IllegalArgumentException(
           "Reusable data mode is not supported without wrapperJsonObject");
     }
+    JsonWriter jsonWriter;
+    if (outputStream != null) {
+      jsonWriter = new StreamJsonWriter(outputStream, TYPE, prettyPrint);
+    } else {
+      Logger writerLogger = outputLogger != null ? outputLogger : this.logger;
+      jsonWriter = new LoggerJsonWriter(writerLogger, TYPE, prettyPrint);
+    }
     return new OtlpStdoutMetricExporter(
         logger,
         jsonWriter,

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/internal/traces/OtlpStdoutSpanExporterBuilder.java

@@ -14,6 +14,7 @@
 import io.opentelemetry.sdk.common.export.MemoryMode;
 import java.io.OutputStream;
 import java.util.logging.Logger;
+import javax.annotation.Nullable;
 
 /**
  * Builder for {@link OtlpJsonLoggingSpanExporter}.
@@ -26,13 +27,14 @@ public final class OtlpStdoutSpanExporterBuilder {
   private static final String TYPE = "spans";
 
   private final Logger logger;
-  private JsonWriter jsonWriter;
+  @Nullable private OutputStream outputStream;
+  @Nullable private Logger outputLogger;
   private boolean wrapperJsonObject = true;
   private MemoryMode memoryMode = MemoryMode.IMMUTABLE_DATA;
+  private boolean prettyPrint;
 
   public OtlpStdoutSpanExporterBuilder(Logger logger) {
     this.logger = logger;
-    this.jsonWriter = new LoggerJsonWriter(logger, TYPE);
   }
 
   /**
@@ -57,6 +59,12 @@ public OtlpStdoutSpanExporterBuilder setMemoryMode(MemoryMode memoryMode) {
     return this;
   }
 
+  /** Sets the exporter to use pretty-printed JSON output. */
+  public OtlpStdoutSpanExporterBuilder setPrettyPrint(boolean prettyPrint) {
+    this.prettyPrint = prettyPrint;
+    return this;
+  }
+
   /**
    * Sets the exporter to use the specified output stream.
    *
@@ -67,14 +75,16 @@ public OtlpStdoutSpanExporterBuilder setMemoryMode(MemoryMode memoryMode) {
    */
   public OtlpStdoutSpanExporterBuilder setOutput(OutputStream outputStream) {
     requireNonNull(outputStream, "outputStream");
-    this.jsonWriter = new StreamJsonWriter(outputStream, TYPE);
+    this.outputStream = outputStream;
+    this.outputLogger = null;
     return this;
   }
 
   /** Sets the exporter to use the specified logger. */
   public OtlpStdoutSpanExporterBuilder setOutput(Logger logger) {
     requireNonNull(logger, "logger");
-    this.jsonWriter = new LoggerJsonWriter(logger, TYPE);
+    this.outputLogger = logger;
+    this.outputStream = null;
     return this;
   }
 
@@ -88,6 +98,13 @@ public OtlpStdoutSpanExporter build() {
       throw new IllegalArgumentException(
           "Reusable data mode is not supported without wrapperJsonObject");
     }
+    JsonWriter jsonWriter;
+    if (outputStream != null) {
+      jsonWriter = new StreamJsonWriter(outputStream, TYPE, prettyPrint);
+    } else {
+      Logger writerLogger = outputLogger != null ? outputLogger : this.logger;
+      jsonWriter = new LoggerJsonWriter(writerLogger, TYPE, prettyPrint);
+    }
     return new OtlpStdoutSpanExporter(logger, jsonWriter, wrapperJsonObject, memoryMode);
   }
 }

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/internal/writer/LoggerJsonWriter.java

@@ -23,16 +23,25 @@ public class LoggerJsonWriter implements JsonWriter {
 
   private final Logger logger;
   private final String type;
+  private final boolean prettyPrint;
 
   public LoggerJsonWriter(Logger logger, String type) {
+    this(logger, type, /* prettyPrint= */ false);
+  }
+
+  public LoggerJsonWriter(Logger logger, String type, boolean prettyPrint) {
     this.logger = logger;
     this.type = type;
+    this.prettyPrint = prettyPrint;
   }
 
   @Override
   public CompletableResultCode write(Marshaler exportRequest) {
     SegmentedStringWriter sw = new SegmentedStringWriter(JSON_FACTORY._getBufferRecycler());
     try (JsonGenerator gen = JsonUtil.create(sw)) {
+      if (prettyPrint) {
+        gen.useDefaultPrettyPrinter();
+      }
       exportRequest.writeJsonToGenerator(gen);
     } catch (IOException e) {
       logger.log(Level.WARNING, "Unable to write OTLP JSON " + type, e);

exporters/logging-otlp/src/main/java/io/opentelemetry/exporter/logging/otlp/internal/writer/StreamJsonWriter.java

@@ -29,19 +29,29 @@ public class StreamJsonWriter implements JsonWriter {
 
   private final String type;
   private final OutputStream outputStream;
+  private final boolean prettyPrint;
 
   public StreamJsonWriter(OutputStream originalStream, String type) {
+    this(originalStream, type, /* prettyPrint= */ false);
+  }
+
+  public StreamJsonWriter(OutputStream originalStream, String type, boolean prettyPrint) {
     this.outputStream = originalStream;
     this.type = type;
+    this.prettyPrint = prettyPrint;
   }
 
   @Override
   public CompletableResultCode write(Marshaler exportRequest) {
     try {
-      exportRequest.writeJsonWithNewline(
+      JsonGenerator generator =
           JSON_FACTORY
               .createGenerator(outputStream)
-              .disable(JsonGenerator.Feature.AUTO_CLOSE_TARGET));
+              .disable(JsonGenerator.Feature.AUTO_CLOSE_TARGET);
+      if (prettyPrint) {
+        generator.useDefaultPrettyPrinter();
+      }
+      exportRequest.writeJsonWithNewline(generator);
       return CompletableResultCode.ofSuccess();
     } catch (IOException e) {
       logger.log(Level.WARNING, "Unable to write OTLP JSON " + type, e);

exporters/logging-otlp/src/test/java/io/opentelemetry/exporter/logging/otlp/OtlpJsonLoggingLogRecordExporterTest.java

@@ -42,7 +42,7 @@ void log() throws Exception {
     String message = logs.getEvents().get(0).getMessage();
     String expectedJson = testDataExporter.getExpectedJson(false);
     JSONAssert.assertEquals("Got \n" + message, expectedJson, message, /* strict= */ false);
-    assertThat(message).doesNotContain("\n");
+    assertThat(message).contains("\n");
   }
 
   @Test

exporters/logging-otlp/src/test/java/io/opentelemetry/exporter/logging/otlp/OtlpJsonLoggingMetricExporterTest.java

@@ -57,7 +57,7 @@ void log() throws Exception {
     String message = logs.getEvents().get(0).getMessage();
     String expectedJson = testDataExporter.getExpectedJson(false);
     JSONAssert.assertEquals("Got \n" + message, expectedJson, message, /* strict= */ false);
-    assertThat(message).doesNotContain("\n");
+    assertThat(message).contains("\n");
   }
 
   @Test