From 3acbee458249c359397cd3cfb3f8300ccc7f62e8 Mon Sep 17 00:00:00 2001
From: Benoit Sigoure <benoit@nexthop.ai>
Date: Wed, 11 Feb 2026 13:01:59 +0000
Subject: [PATCH] Auto-derive AgentURL from MetadataURL or CallbackURL if not
 set

When AgentURL is not explicitly configured, derive it automatically
from MetadataURL (or CallbackURL as fallback) by taking the base URL
and setting the path to /agent.

This makes AgentURL effectively optional for users who use the standard
URL structure, reducing configuration burden when upgrading to versions
that require agent mode support.
---
 database/sql/controller.go | 30 +++++++++++++++++++++++++++---
 1 file changed, 27 insertions(+), 3 deletions(-)

diff --git a/database/sql/controller.go b/database/sql/controller.go
index 2285f6be..8af9c4f5 100644
--- a/database/sql/controller.go
+++ b/database/sql/controller.go
@@ -19,6 +19,7 @@ import (
 	"fmt"
 	"log/slog"
 	"net/url"
+	"strings"
 	"time"
 
 	"github.com/google/uuid"
@@ -31,8 +32,21 @@ import (
 	"github.com/cloudbase/garm/util/appdefaults"
 )
 
+// inferAgentURL extracts the base URL (scheme://host) from a given URL.
+// This is used to derive the AgentURL from CallbackURL when AgentURL is not explicitly set.
+func inferAgentURL(uri string) (string, error) {
+	if uri == "" {
+		return "", runnerErrors.NewConflictError("URL cannot be empty")
+	}
+	parsed, err := url.ParseRequestURI(uri)
+	if err != nil {
+		return "", fmt.Errorf("failed to parse URL: %w", err)
+	}
+	return strings.TrimSuffix(fmt.Sprintf("%s://%s", parsed.Scheme, parsed.Host), "/"), nil
+}
+
 func dbControllerToCommonController(dbInfo ControllerInfo) (params.ControllerInfo, error) {
-	url, err := url.JoinPath(dbInfo.WebhookBaseURL, dbInfo.ControllerID.String())
+	webhookURL, err := url.JoinPath(dbInfo.WebhookBaseURL, dbInfo.ControllerID.String())
 	if err != nil {
 		return params.ControllerInfo{}, fmt.Errorf("error joining webhook URL: %w", err)
 	}
@@ -41,13 +55,23 @@ func dbControllerToCommonController(dbInfo ControllerInfo) (params.ControllerInf
 		dbInfo.GARMAgentReleasesURL = appdefaults.GARMAgentDefaultReleasesURL
 	}
 
+	// If AgentURL is not set, derive it from CallbackURL
+	agentURL := dbInfo.AgentURL
+	if agentURL == "" {
+		var err error
+		agentURL, err = inferAgentURL(dbInfo.CallbackURL)
+		if err != nil {
+			slog.Warn("failed to infer agent URL; please update controller info with proper URL", "error", err)
+		}
+	}
+
 	ret := params.ControllerInfo{
 		ControllerID:                    dbInfo.ControllerID,
 		MetadataURL:                     dbInfo.MetadataURL,
 		WebhookURL:                      dbInfo.WebhookBaseURL,
-		ControllerWebhookURL:            url,
+		ControllerWebhookURL:            webhookURL,
 		CallbackURL:                     dbInfo.CallbackURL,
-		AgentURL:                        dbInfo.AgentURL,
+		AgentURL:                        agentURL,
 		MinimumJobAgeBackoff:            dbInfo.MinimumJobAgeBackoff,
 		Version:                         appdefaults.GetVersion(),
 		GARMAgentReleasesURL:            dbInfo.GARMAgentReleasesURL,