Expose setTrustedCertificates in JaegerGrpcSpanExporterBuilder for mT…

…LS Support (#4061)

* adding setTrustedCertificates to JaegerGrpcSpanExporterBuilder for mTLS support

* fixing formatting error

* added setTrustedCertificates to JaegerGrpcSpanExporterBuilder

* added validConfig test for setTrustedCertificates mTLS support

* removing unnecessary comments

docs/apidiffs/current_vs_latest/opentelemetry-exporter-jaeger.txt

@@ -1,2 +1,4 @@
 Comparing source compatibility of  against 
-No changes.
+***  MODIFIED CLASS: PUBLIC FINAL io.opentelemetry.exporter.jaeger.JaegerGrpcSpanExporterBuilder  (not serializable)
+	===  CLASS FILE FORMAT VERSION: 52.0 <- 52.0
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.exporter.jaeger.JaegerGrpcSpanExporterBuilder setTrustedCertificates(byte[])

exporters/jaeger/src/main/java/io/opentelemetry/exporter/jaeger/JaegerGrpcSpanExporterBuilder.java

@@ -83,6 +83,16 @@ public JaegerGrpcSpanExporterBuilder setTimeout(Duration timeout) {
     return this;
   }
 
+  /**
+   * Sets the certificate chain to use for verifying servers when TLS is enabled. The {@code byte[]}
+   * should contain an X.509 certificate collection in PEM format. If not set, TLS connections will
+   * use the system default trusted certificates.
+   */
+  public JaegerGrpcSpanExporterBuilder setTrustedCertificates(byte[] trustedCertificatesPem) {
+    delegate.setTrustedCertificates(trustedCertificatesPem);
+    return this;
+  }
+
   /**
    * Constructs a new instance of the exporter based on the builder's values.
    *

exporters/jaeger/src/test/java/io/opentelemetry/exporter/jaeger/JaegerGrpcSpanExporterTest.java

@@ -6,6 +6,7 @@
 package io.opentelemetry.exporter.jaeger;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatCode;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.junit.jupiter.api.Assertions.fail;
 
@@ -33,6 +34,7 @@
 import io.opentelemetry.semconv.resource.attributes.ResourceAttributes;
 import java.net.InetAddress;
 import java.net.URISyntaxException;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -286,6 +288,16 @@ private static Optional<Model.KeyValue> getTagValue(List<Model.KeyValue> tags, S
     return tags.stream().filter(kv -> kv.getKey().equals(tagKey)).findFirst();
   }
 
+  @Test
+  @SuppressWarnings("PreferJavaTimeOverload")
+  void validConfig() {
+    assertThatCode(
+            () ->
+                JaegerGrpcSpanExporter.builder()
+                    .setTrustedCertificates("foobar".getBytes(StandardCharsets.UTF_8)))
+        .doesNotThrowAnyException();
+  }
+
   @Test
   @SuppressWarnings("PreferJavaTimeOverload")
   void invalidConfig() {