Logging: Allow deferred formatting for trace and spanId

google-cloud-clients/google-cloud-logging/src/main/java/com/google/cloud/logging/LogEntry.java

@@ -65,8 +65,8 @@ public LogEntry apply(com.google.logging.v2.LogEntry pb) {
   private final HttpRequest httpRequest;
   private final Map<String, String> labels;
   private final Operation operation;
-  private final String trace;
-  private final String spanId;
+  private final Object trace;
+  private final Object spanId;
   private final boolean traceSampled;
   private final SourceLocation sourceLocation;
   private final Payload<?> payload;
@@ -85,8 +85,8 @@ public static class Builder {
     private HttpRequest httpRequest;
     private Map<String, String> labels = new HashMap<>();
     private Operation operation;
-    private String trace;
-    private String spanId;
+    private Object trace;
+    private Object spanId;
     private boolean traceSampled;
     private SourceLocation sourceLocation;
     private Payload<?> payload;
@@ -223,7 +223,6 @@ public Builder setOperation(Operation operation) {
       return this;
     }
 
-
     /**
      * Sets the resource name of the trace associated with the log entry, if any. If it contains a
      * relative resource name, the name is assumed to be relative to `//tracing.googleapis.com`.
@@ -233,6 +232,14 @@ public Builder setTrace(String trace) {
       return this;
     }
 
+    /**
+     * Sets the resource name of the trace associated with the log entry, if any. If it contains a
+     * relative resource name, the name is assumed to be relative to `//tracing.googleapis.com`.
+     */
+    public Builder setTrace(Object trace) {
+      this.trace = trace;
+      return this;
+    }
 
     /**
      * Sets the ID of the trace span associated with the log entry, if any.
@@ -242,6 +249,14 @@ public Builder setSpanId(String spanId) {
       return this;
     }
 
+    /**
+     * Sets the ID of the trace span associated with the log entry, if any.
+     */
+    public Builder setSpanId(Object spanId) {
+      this.spanId = spanId;
+      return this;
+    }
+
 
     /**
      * Sets the sampling decision of the trace span associated with the log entry.
@@ -385,15 +400,17 @@ public Operation getOperation() {
    * relative resource name, the name is assumed to be relative to `//tracing.googleapis.com`.
    */
   public String getTrace() {
-    return trace;
+    // For backwards compatibility return null when trace not set instead of "null".
+    return trace == null ? null : String.valueOf(trace);
   }
 
 
   /**
    * Returns the ID of the trace span associated with the log entry, if any.
    */
   public String getSpanId() {
-    return spanId;
+    // For backwards compatibility return null when spanId not set instead of "null".
+    return spanId == null ? null : String.valueOf(spanId);
   }
 
 
@@ -429,7 +446,7 @@ public <T extends Payload> T getPayload() {
   @Override
   public int hashCode() {
     return Objects.hash(logName, resource, timestamp, receiveTimestamp, severity, insertId,
-        httpRequest, labels, operation, trace, spanId, traceSampled, sourceLocation, payload);
+        httpRequest, labels, operation, getTrace(), getSpanId(), traceSampled, sourceLocation, payload);
   }
 
   @Override
@@ -450,8 +467,8 @@ public boolean equals(Object obj) {
         && Objects.equals(httpRequest, other.httpRequest)
         && Objects.equals(labels, other.labels)
         && Objects.equals(operation, other.operation)
-        && Objects.equals(trace, other.trace)
-        && Objects.equals(spanId, other.spanId)
+        && Objects.equals(getTrace(), other.getTrace())
+        && Objects.equals(getSpanId(), other.getSpanId())
         && Objects.equals(traceSampled, other.traceSampled)
         && Objects.equals(sourceLocation, other.sourceLocation)
         && Objects.equals(payload, other.payload);
@@ -524,10 +541,10 @@ com.google.logging.v2.LogEntry toPb(String projectId) {
       builder.setOperation(operation.toPb());
     }
     if (trace != null) {
-      builder.setTrace(trace);
+      builder.setTrace(getTrace());
     }
     if (spanId != null) {
-      builder.setSpanId(spanId);
+      builder.setSpanId(getSpanId());
     }
     builder.setTraceSampled(traceSampled);
     if (sourceLocation != null) {

google-cloud-clients/google-cloud-logging/src/test/java/com/google/cloud/logging/LogEntryTest.java

@@ -51,7 +51,19 @@ public class LogEntryTest {
       ImmutableMap.of("key1", "value1", "key2", "value2");
   private static final Operation OPERATION = Operation.of("id", "producer");
   private static final String TRACE = "trace";
+  private static final Object TRACE_FORMATTER = new Object() {
+    @Override
+    public String toString() {
+      return TRACE;
+    }
+  };
   private static final String SPAN_ID = "spanId";
+  private static final Object SPAN_ID_FORMATTER = new Object() {
+    @Override
+    public String toString() {
+      return SPAN_ID;
+    }
+  };
   private static final boolean TRACE_SAMPLED = true;
   private static final SourceLocation SOURCE_LOCATION = new SourceLocation.Builder()
       .setFile("file")
@@ -73,8 +85,8 @@ public class LogEntryTest {
       .setHttpRequest(HTTP_REQUEST)
       .setLabels(LABELS)
       .setOperation(OPERATION)
-      .setTrace(TRACE)
-      .setSpanId(SPAN_ID)
+      .setTrace(TRACE_FORMATTER)
+      .setSpanId(SPAN_ID_FORMATTER)
       .setTraceSampled(TRACE_SAMPLED)
       .setSourceLocation(SOURCE_LOCATION)
       .build();
@@ -88,8 +100,8 @@ public class LogEntryTest {
       .setHttpRequest(HTTP_REQUEST)
       .setLabels(LABELS)
       .setOperation(OPERATION)
-      .setTrace(TRACE)
-      .setSpanId(SPAN_ID)
+      .setTrace(TRACE_FORMATTER)
+      .setSpanId(SPAN_ID_FORMATTER)
       .setTraceSampled(TRACE_SAMPLED)
       .setSourceLocation(SOURCE_LOCATION)
       .build();
@@ -103,8 +115,8 @@ public class LogEntryTest {
       .setHttpRequest(HTTP_REQUEST)
       .setLabels(LABELS)
       .setOperation(OPERATION)
-      .setTrace(TRACE)
-      .setSpanId(SPAN_ID)
+      .setTrace(TRACE_FORMATTER)
+      .setSpanId(SPAN_ID_FORMATTER)
       .setTraceSampled(TRACE_SAMPLED)
       .setSourceLocation(SOURCE_LOCATION)
       .build();