From 40f76efec96c6df2c61c9e816060b288f5c980e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sybren=20A=2E=20St=C3=BCvel?= <sybren@blender.org>
Date: Sun, 15 Oct 2023 14:37:15 +0200
Subject: [PATCH] Shaman: log a warning on platforms that don't reliably
 support symlinks

Windows 10 Home does not support symlinks, and Shaman will cause errors
unless running as admin (which is not recommended for security reasons).
Now Flamenco Manager will log a warning when Shaman is enabled on this
platform.
---
 pkg/shaman/server.go | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/pkg/shaman/server.go b/pkg/shaman/server.go
index 556dc1e1..61a2649e 100644
--- a/pkg/shaman/server.go
+++ b/pkg/shaman/server.go
@@ -25,6 +25,7 @@ package shaman
 import (
 	"context"
 	"io"
+	"runtime"
 	"sync"
 
 	"github.com/rs/zerolog/log"
@@ -34,6 +35,7 @@ import (
 	"projects.blender.org/studio/flamenco/pkg/shaman/fileserver"
 	"projects.blender.org/studio/flamenco/pkg/shaman/filestore"
 	"projects.blender.org/studio/flamenco/pkg/shaman/jwtauth"
+	"projects.blender.org/studio/flamenco/pkg/sysinfo"
 )
 
 var ErrDoesNotExist = checkout.ErrDoesNotExist
@@ -58,6 +60,8 @@ func NewServer(conf config.Config, auther jwtauth.Authenticator) *Server {
 		return nil
 	}
 
+	checkPlatformSymlinkSupport()
+
 	if conf.StoragePath == "" {
 		log.Error().Interface("config", conf).Msg("shaman: no checkout path configured, unable to start")
 		return nil
@@ -81,6 +85,33 @@ func NewServer(conf config.Config, auther jwtauth.Authenticator) *Server {
 	return shamanServer
 }
 
+func checkPlatformSymlinkSupport() {
+	canSymlink, err := sysinfo.CanSymlink()
+	switch {
+	case err != nil:
+		log.Warn().AnErr("cause", err).
+			Msg("unable to determine whether this platform can use symlinks. " +
+				"Please report a bug about this: https://flamenco.blender.org/development/get-involved/")
+		return
+	case canSymlink:
+		return
+	}
+
+	osDetail, err := sysinfo.Description()
+	if err != nil {
+		log.Warn().AnErr("cause", err).
+			Msg("unable to find details of your operating system. " +
+				"Please report a bug about this: https://flamenco.blender.org/development/get-involved/")
+		return
+	}
+
+	log.Warn().
+		Str("os", runtime.GOOS).
+		Str("arch", runtime.GOARCH).
+		Str("osDetail", osDetail).
+		Msg("this platform does not reliably support symbolic links; using the Shaman system is not recommended")
+}
+
 // Go starts goroutines for background operations.
 // After Go() has been called, use Close() to stop those goroutines.
 func (s *Server) Go() {