[release/v1.54.x] Update Prometheus Exporter dependencies to use no-protobuf formats (and adds test) (#7670)

Co-authored-by: Gregor Zeitlinger <[email protected]>

Author: otelbot[bot]

exporters/prometheus/build.gradle.kts

@@ -15,15 +15,14 @@ dependencies {
   implementation("io.prometheus:prometheus-metrics-exporter-httpserver") {
     exclude(group = "io.prometheus", module = "prometheus-metrics-exposition-formats")
   }
-  implementation("io.prometheus:prometheus-metrics-exposition-textformats")
+  implementation("io.prometheus:prometheus-metrics-exposition-formats-no-protobuf")
 
   compileOnly("com.google.auto.value:auto-value-annotations")
 
   annotationProcessor("com.google.auto.value:auto-value")
 
   testImplementation(project(":sdk:testing"))
   testImplementation("io.opentelemetry.proto:opentelemetry-proto")
-  testImplementation("io.prometheus:prometheus-metrics-exposition-formats-no-protobuf")
   testImplementation("com.sun.net.httpserver:http")
   testImplementation("com.google.guava:guava")
   testImplementation("com.linecorp.armeria:armeria")

exporters/prometheus/src/test/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServerTest.java

@@ -239,6 +239,25 @@ void fetchOpenMetrics() {
                 + "# EOF\n");
   }
 
+  @Test
+  void fetchProtobuf() {
+    AggregatedHttpResponse response =
+        client
+            .execute(
+                RequestHeaders.of(
+                    HttpMethod.GET,
+                    "/metrics",
+                    HttpHeaderNames.ACCEPT,
+                    "Accept: application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily"))
+            .aggregate()
+            .join();
+    assertThat(response.status()).isEqualTo(HttpStatus.OK);
+    assertThat(response.headers().get(HttpHeaderNames.CONTENT_TYPE))
+        .isEqualTo(
+            "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited");
+    // don't decode the protobuf, just verify it doesn't throw an exception
+  }
+
   @SuppressWarnings("ConcatenationWithEmptyString")
   @Test
   void fetchFiltered() {

sdk-extensions/autoconfigure/build.gradle.kts

@@ -52,7 +52,9 @@ testing {
         implementation(project(":exporters:logging-otlp"))
         implementation(project(":exporters:otlp:all"))
         implementation(project(":exporters:prometheus"))
-        implementation("io.prometheus:prometheus-metrics-exporter-httpserver")
+        implementation("io.prometheus:prometheus-metrics-exporter-httpserver") {
+          exclude(group = "io.prometheus", module = "prometheus-metrics-exposition-formats")
+        }
         implementation(project(":exporters:zipkin"))
         implementation(project(":sdk:testing"))
         implementation(project(":sdk:trace-shaded-deps"))