From 86831a3ce493f2e8343e1a52984f6ce36ba164d0 Mon Sep 17 00:00:00 2001
From: Gabriel Radureau <arcodange@gmail.com>
Date: Tue, 5 May 2026 10:17:22 +0200
Subject: [PATCH] =?UTF-8?q?=E2=9C=A8=20feat(server):=20add=20go=5Fversion?=
 =?UTF-8?q?=20to=20/api/info=20response?=
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Adds a "go_version" field to InfoResponse, populated via runtime.Version().
Useful for ops debugging (which Go version is running in production?).
BDD scenario @critical asserts the field is non-empty. Doc + ADR-0026
updated.
---
 adr/0026-composite-info-endpoint.md | 5 ++++-
 documentation/API.md                | 3 ++-
 features/info/info.feature          | 7 +++++++
 pkg/server/server.go                | 3 +++
 4 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/adr/0026-composite-info-endpoint.md b/adr/0026-composite-info-endpoint.md
index 4230763..59826ba 100644
--- a/adr/0026-composite-info-endpoint.md
+++ b/adr/0026-composite-info-endpoint.md
@@ -141,10 +141,13 @@ We will implement a new `GET /api/info` endpoint that returns a JSON object with
   "build_date": "2026-05-04T08:00:00Z",
   "uptime_seconds": 1234,
   "cache_enabled": true,
-  "healthz_status": "healthy"
+  "healthz_status": "healthy",
+  "go_version": "go1.26.1"
 }
 ```
 
+The `go_version` field provides the Go runtime version via `runtime.Version()`, useful for ops debugging (e.g., identifying which Go version is running in production).
+
 ### Rationale
 
 1. **Performance**: Single HTTP request instead of 3-4 separate calls
diff --git a/documentation/API.md b/documentation/API.md
index 8f10c57..8367787 100644
--- a/documentation/API.md
+++ b/documentation/API.md
@@ -30,7 +30,8 @@ Reference document for all HTTP endpoints exposed by `dance-lessons-coach` serve
   "build_date": "2026-05-05",
   "uptime_seconds": 1234,
   "cache_enabled": true,
-  "healthz_status": "healthy"
+  "healthz_status": "healthy",
+  "go_version": "go1.26.1"
 }
 ```
 
diff --git a/features/info/info.feature b/features/info/info.feature
index 8e36e4c..7d55cb8 100644
--- a/features/info/info.feature
+++ b/features/info/info.feature
@@ -36,3 +36,10 @@ Feature: Info Endpoint
     Then the response header "X-Cache" should be "MISS"
     When I request the info endpoint again
     Then the response header "X-Cache" should be "HIT"
+
+  @go_version @critical
+  Scenario: go_version field is non-empty
+    Given the server is running
+    When I request the info endpoint
+    Then the status code should be 200
+    And the response should contain "go_version"
diff --git a/pkg/server/server.go b/pkg/server/server.go
index 0e0fc2a..5f65e0f 100644
--- a/pkg/server/server.go
+++ b/pkg/server/server.go
@@ -9,6 +9,7 @@ import (
 	"net"
 	"net/http"
 	"os/signal"
+	"runtime"
 	"syscall"
 	"time"
 
@@ -453,6 +454,7 @@ type InfoResponse struct {
 	UptimeSeconds int64  `json:"uptime_seconds"`
 	CacheEnabled  bool   `json:"cache_enabled"`
 	HealthzStatus string `json:"healthz_status"`
+	GoVersion     string `json:"go_version"`
 }
 
 // handleHealthz godoc
@@ -500,6 +502,7 @@ func (s *Server) handleInfo(w http.ResponseWriter, r *http.Request) {
 		UptimeSeconds: int64(time.Since(s.startedAt).Seconds()),
 		CacheEnabled:  s.cacheService != nil,
 		HealthzStatus: "healthy",
+		GoVersion:     runtime.Version(),
 	}
 
 	// Cache key