Add micrometer.prometheus-proxy.connected-metrics-metadata property

Signed-off-by: Mateo00 <[email protected]>

Author: Mateo00

proxy-server/src/main/java/io/micrometer/prometheus/rsocket/PrometheusController.java

@@ -121,7 +121,7 @@ private Mono<RSocket> acceptRSocket(KeyPairGenerator generator, RSocket sendingS
     // respond with Mono.error(..) to
     RSocket metricsInterceptedSendingSocket = metricsInterceptor.apply(sendingSocket);
 
-    ConnectionState connectionState = new ConnectionState(generator.generateKeyPair());
+    ConnectionState connectionState = new ConnectionState(generator.generateKeyPair(), this.properties);
     scrapableApps.put(metricsInterceptedSendingSocket, connectionState);
 
     // a key to be used by the client to push metrics as it's dying if this happens before the first scrape
@@ -186,12 +186,14 @@ public Mono<String> prometheus() {
 
   class ConnectionState {
     private final KeyPair keyPair;
+    private final PrometheusControllerProperties properties;
 
     // the last metrics of a dying application instance
     private String dyingPush;
 
-    ConnectionState(KeyPair keyPair) {
+    ConnectionState(KeyPair keyPair, PrometheusControllerProperties properties) {
       this.keyPair = keyPair;
+      this.properties = properties;
     }
 
     Mono<String> getDyingPush() {
@@ -211,6 +213,9 @@ String receiveScrapePayload(Payload payload, Timer.Sample timing) {
             ByteBufUtil.getBytes(sliceData, sliceData.readerIndex(), sliceData.readableBytes(), false));
 
         String uncompressed = Snappy.uncompressString(decrypted);
+        if (!this.properties.getConnectedMetricsMetadata()) {
+          uncompressed = uncompressed.replaceAll("(?m)^#.*\n", "");
+        }
         scrapePayload.record(uncompressed.length());
         return uncompressed;
       } catch (IOException e) {
@@ -246,4 +251,4 @@ Payload createKeyPayload() {
       return DefaultPayload.create(keyPair.getPublic().getEncoded());
     }
   }
-}
+}

proxy-server/src/main/java/io/micrometer/prometheus/rsocket/PrometheusControllerProperties.java

@@ -33,6 +33,12 @@ public class PrometheusControllerProperties {
    */
   private int websocketPort = 8081;
 
+  /**
+   * Whether to enable publishing of Prometheus metadata (lines "# HELP ..." and lines "# TYPE ...") in the payload returned by the /metrics/connected endpoint.
+   * Disabling metadata publishing reduces the amount of data sent sent on each scrape.
+   */
+  private boolean connectedMetricsMetadata = true;
+
   public int getTcpPort() {
     return tcpPort;
   }
@@ -48,4 +54,12 @@ public int getWebsocketPort() {
   public void setWebsocketPort(int websocketPort) {
     this.websocketPort = websocketPort;
   }
+
+  public boolean getConnectedMetricsMetadata() {
+    return connectedMetricsMetadata;
+  }
+
+  public void setConnectedMetricsMetadata(boolean connectedMetricsMetadata) {
+    this.connectedMetricsMetadata = connectedMetricsMetadata;
+  }
 }