Log output to TEMP/jfa-go.log when Tray enabled

-H=windowsgui completely disables Stdout/Stderr on Windows, so logging
is enabled.

README.md

@@ -8,6 +8,9 @@
 ---
 jfa-go is a user management app for [Jellyfin](https://github.com/jellyfin/jellyfin) (and now [Emby](https://emby.media/)) that provides invite-based account creation as well as other features that make one's instance much easier to manage.
 
+a rewrite of [jellyfin-accounts](https://github.com/hrfee/jellyfin-accounts) (original naming for both, ik 
+😂).
+
 #### Features
 * 🧑 Invite based account creation: Send invites to your friends or family, and let them choose their own username and password without relying on you.
     * Send invites via a link and/or email

go.mod

@@ -47,8 +47,8 @@ require (
 	github.com/ugorji/go v1.2.0 // indirect
 	github.com/writeas/go-strip-markdown v2.0.1+incompatible
 	golang.org/x/crypto v0.0.0-20201112155050-0c6587e931a9 // indirect
-	golang.org/x/net v0.0.0-20210521195947-fe42d452be8f // indirect
-	golang.org/x/sys v0.0.0-20210521203332-0cec03c779c1 // indirect
+	golang.org/x/net v0.0.0-20210525063256-abc453219eb5 // indirect
+	golang.org/x/sys v0.0.0-20210525143221-35b2ab0089ea // indirect
 	golang.org/x/tools v0.1.1 // indirect
 	google.golang.org/protobuf v1.25.0 // indirect
 	gopkg.in/ini.v1 v1.62.0

go.sum

@@ -308,6 +308,8 @@ golang.org/x/net v0.0.0-20210510120150-4163338589ed h1:p9UgmWI9wKpfYmgaV/IZKGdXc
 golang.org/x/net v0.0.0-20210510120150-4163338589ed/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20210521195947-fe42d452be8f h1:Si4U+UcgJzya9kpiEUJKQvjr512OLli+gL4poHrz93U=
 golang.org/x/net v0.0.0-20210521195947-fe42d452be8f/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.0.0-20210525063256-abc453219eb5 h1:wjuX4b5yYQnEQHzd+CBcrcC6OVR2J1CN6mUy0oSxIPo=
+golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be h1:vEDujvNQGv4jgYKudGeI/+DAX4Jffq6hpD55MmoEvKs=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -342,6 +344,8 @@ golang.org/x/sys v0.0.0-20210514084401-e8d321eab015 h1:hZR0X1kPW+nwyJ9xRxqZk1vx5
 golang.org/x/sys v0.0.0-20210514084401-e8d321eab015/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210521203332-0cec03c779c1 h1:lCnv+lfrU9FRPGf8NeRuWAAPjNnema5WtBinMgs1fD8=
 golang.org/x/sys v0.0.0-20210521203332-0cec03c779c1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210525143221-35b2ab0089ea h1:+WiDlPBBaO+h9vPNZi8uJ3k4BkKQB7Iow3aqwHVA5hI=
+golang.org/x/sys v0.0.0-20210525143221-35b2ab0089ea/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1 h1:v+OssWQX+hTHEmOBgwxdZxK4zHq3yOs8F9J7mk0PY8E=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

main.go

@@ -6,6 +6,7 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
+	"io"
 	"io/fs"
 	"log"
 	"mime"
@@ -20,6 +21,7 @@ import (
 	"time"
 
 	"github.com/fatih/color"
+	"github.com/gin-gonic/gin"
 	"github.com/hrfee/jfa-go/common"
 	_ "github.com/hrfee/jfa-go/docs"
 	"github.com/hrfee/jfa-go/logger"
@@ -58,6 +60,8 @@ var temp = func() string {
 	return temp
 }()
 
+var logPath string = filepath.Join(temp, "jfa-go.log")
+
 var serverTypes = map[string]string{
 	"jellyfin": "Jellyfin",
 	"emby":     "Emby (experimental)",
@@ -715,7 +719,34 @@ func printVersion() {
 	fmt.Println(info("jfa-go version: %s (%s)%s\n", hiwhite(version), white(commit), tray))
 }
 
+func logOutput() func() {
+	old := os.Stdout
+	log.Printf("Logging to \"%s\"", logPath)
+	f, err := os.OpenFile(logPath, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+	if err == nil {
+		return func() {}
+	}
+	writer := io.MultiWriter(old, f)
+	r, w, _ := os.Pipe()
+	os.Stdout, os.Stderr = w, w
+	log.SetOutput(writer)
+	gin.DefaultWriter, gin.DefaultErrorWriter = writer, writer
+	wExit := make(chan bool)
+	go func() {
+		io.Copy(writer, r)
+		wExit <- true
+	}()
+	return func() {
+		w.Close()
+		<-wExit
+		f.Close()
+	}
+}
+
 func main() {
+	if TRAY {
+		defer logOutput()()
+	}
 	printVersion()
 	SOCK = filepath.Join(temp, SOCK)
 	fmt.Println("Socket:", SOCK)