From 6ea435c3d3e8fe4a4fae3c9514584836f2835811 Mon Sep 17 00:00:00 2001
From: Asger Noer <55031664+asger-noer@users.noreply.github.com>
Date: Mon, 22 Jan 2024 11:39:57 +1300
Subject: [PATCH] feat: overwrite with environment variable

---
 docs/configuration.md | 2 +-
 telemetry.go          | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/docs/configuration.md b/docs/configuration.md
index a66c8f94..094c9dc1 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -98,7 +98,7 @@ Sample configuration:
     - Default: `false`
     - Supports hot-reload: No
   - `endpoint`: OpenTelemetry collector endpoint.
-    - Default: If no endpoint is specified, telemetry is disabled.
+    - Default: If no endpoint is specified, telemetry is disabled. Bramble will check for `BRAMBLE_OTEL_ENDPOINT` environment variable and use it if set.
     - Supports hot-reload: No
   - `serviceName`: Service name to use for OpenTelemetry.
     - Default: `bramble`
diff --git a/telemetry.go b/telemetry.go
index f14ea6c7..a40caf63 100644
--- a/telemetry.go
+++ b/telemetry.go
@@ -3,6 +3,7 @@ package bramble
 import (
 	"context"
 	"errors"
+	"os"
 
 	"github.com/sirupsen/logrus"
 	"go.opentelemetry.io/otel"
@@ -41,6 +42,11 @@ func (e *TelemetryErrHandler) Handle(err error) {
 // returns a shutdown function that should be called when the application
 // terminates.
 func InitTelemetry(ctx context.Context, cfg TelemetryConfig) (func(context.Context) error, error) {
+	endpoint := os.Getenv("BRAMBLE_OTEL_ENDPOINT")
+	if endpoint != "" {
+		cfg.Endpoint = endpoint
+	}
+
 	// If telemetry is disabled, return a no-op shutdown function. The standard
 	// behaviour of the application will not be affected, since a
 	// `NoopTracerProvider` is used by default.