From 5ba1edf6480d9fefc7c7fd587ce0728c0ce1d550 Mon Sep 17 00:00:00 2001
From: Pratik Mankawde <3397372+pratikmankawde@users.noreply.github.com>
Date: Thu, 3 Sep 2026 16:47:25 +0100
Subject: [PATCH] fix(telemetry): use metrics_endpoint verbatim in initMetrics

initMetrics() held its own copy of the suffix-swap: take tracesEndpoint,
replace a trailing /v1/traces with /v1/metrics. Any other URL shape sent
metrics to the traces path. metrics_endpoint is now a config key of its
own, so use it as given.

Application::startTelemetry() still reads the key itself for
MetricsRegistry, which builds its own exporter. Telemetry exposes no
accessor for the Setup it parsed, and re-parsing would re-run the mTLS
validation and cert-file checks at a later point in startup, so the
second read stays. The comment above it no longer claims the URL is
derived from the traces one.

Also corrects 05-configuration-reference.md: the sample configs carry
metrics_endpoint where exporter used to sit, not a comment.
---
 OpenTelemetryPlan/05-configuration-reference.md | 11 ++++-------
 src/libxrpl/telemetry/Telemetry.cpp             | 16 +++-------------
 src/xrpld/app/main/Application.cpp              |  5 +++--
 3 files changed, 10 insertions(+), 22 deletions(-)

diff --git a/OpenTelemetryPlan/05-configuration-reference.md b/OpenTelemetryPlan/05-configuration-reference.md
index a5dec3fc52..10bdfa87cd 100644
--- a/OpenTelemetryPlan/05-configuration-reference.md
+++ b/OpenTelemetryPlan/05-configuration-reference.md
@@ -113,13 +113,10 @@ the corresponding subsystems are instrumented:
 | `trace_validator` | Future        | Validator list / manifest update tracing |
 | `trace_amendment` | Future        | Amendment voting tracing                 |
 
-> **`exporter` is not read, so do not set it.** Both shipped sample configs
-> (`docker/telemetry/xrpld-telemetry.cfg`,
-> `docker/telemetry/xrpld-telemetry-mainnet.cfg`) used to carry
-> `exporter=otlp_http`; the line had no effect and has since been replaced with
-> a comment saying so. OTLP/HTTP is the only transport that exists (§2.2.1), and
-> `endpoint` / `metrics_endpoint` are the only transport knobs, until the §2.2.2
-> gRPC work lands.
+> **`exporter` is not read, so do not set it.** No shipped sample config
+> carries it. OTLP/HTTP is the only transport that exists (§2.2.1), so
+> `traces_endpoint` and `metrics_endpoint` are the only transport knobs until
+> the §2.2.2 gRPC work lands.
 
 ---
 
diff --git a/src/libxrpl/telemetry/Telemetry.cpp b/src/libxrpl/telemetry/Telemetry.cpp
index 32682b0354..7b54b76c8d 100644
--- a/src/libxrpl/telemetry/Telemetry.cpp
+++ b/src/libxrpl/telemetry/Telemetry.cpp
@@ -529,21 +529,11 @@ public:
     void
     initMetrics()
     {
-        // Derive the metrics endpoint from the trace endpoint by swapping
-        // the trailing "/v1/traces" path for "/v1/metrics". Any other URL
-        // shape is used as-is.
-        std::string metricsEndpoint = setup_.tracesEndpoint;
-        constexpr std::string_view tracesPath{"/v1/traces"};
-        if (metricsEndpoint.ends_with(tracesPath))
-        {
-            metricsEndpoint.replace(
-                metricsEndpoint.size() - tracesPath.size(), tracesPath.size(), "/v1/metrics");
-        }
-
         // Configure OTLP HTTP metric exporter, honoring the same TLS
-        // options as the trace exporter.
+        // options as the trace exporter. The URL is used verbatim: metrics
+        // have their own config key and are not derived from traces.
         otlp_http::OtlpHttpMetricExporterOptions metricExporterOpts;
-        metricExporterOpts.url = metricsEndpoint;
+        metricExporterOpts.url = setup_.metricsEndpoint;
         if (setup_.useTls)
         {
             metricExporterOpts.ssl_ca_cert_path = setup_.tlsCertPath;
diff --git a/src/xrpld/app/main/Application.cpp b/src/xrpld/app/main/Application.cpp
index 30e44bd5df..0615edb543 100644
--- a/src/xrpld/app/main/Application.cpp
+++ b/src/xrpld/app/main/Application.cpp
@@ -1720,8 +1720,9 @@ ApplicationImp::startTelemetry() const
     // Start tracing first so subsequent startup/early activity can be traced.
     telemetry_->start();
 
-    // Start the metrics pipeline after telemetry; the endpoint uses the
-    // same base URL but the /v1/metrics path.
+    // Start the metrics pipeline after telemetry. metrics_endpoint is a full
+    // URL of its own, read again here because Telemetry does not expose the
+    // Setup it parsed.
     if (metricsRegistry_)
     {
         auto const& section = config_->section("telemetry");