feat: load config from flag/env/fallback

README.md

@@ -6,6 +6,21 @@
 go install git.meatbag.se/varl/subsyt@latest
 ```
 
+## running
+
+Configuration can be loaded from a file specified either by the env
+variable `CONFIG` or `--config` flag.
+
+The `--config` flag has priority over `CONFIG` environment variable.
+
+```
+CONFIG="/path/to/config.toml" ./subsyt
+
+./subsyt --config="/patch/to/config"
+
+./subsyt    # assumes "./config.toml"
+```
+
 ## config
 
 `config.toml`:
@@ -53,7 +68,7 @@ opml_file = "./opml.xml"                # the opml file to use
 CGO_ENABLED=0 go build
 ```
 
-## Cookies
+## cookies
 
 > [!WARNING]
 > Your account **MAY** be banned when using cookies !
@@ -64,7 +79,7 @@ E.g. from Chromium:
 yt-dlp --cookies-from-browser chromium --cookies cookies.txt
 ```
 
-## Scheduling
+## scheduling
 
 ### systemd
 
@@ -96,7 +111,7 @@ RandomizedDelaySec=30
 WantedBy=timers.target
 ```
 
-## Container
+## container
 
 ```
 podman run --rm \
@@ -107,7 +122,7 @@ podman run --rm \
     registry.meatbag.se/varl/subsyt
 ```
 
-## Result
+## result
 
 ```
 .
@@ -135,6 +150,6 @@ podman run --rm \
 │   └── tvshow.nfo
 ```
 
-## Generate OPML
+## generate opml
 
 E.g. https://github.com/jeb5/YouTube-Subscriptions-RSS

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"flag"
 	"log"
 	"os"
 	"path/filepath"
@@ -12,12 +13,22 @@ import (
 )
 
 func main() {
-	configPath := os.Getenv("CONFIG")
+	configPtr := flag.String("config", "", "path to config file")
+	flag.Parse()
 
-	if configPath == "" {
+	configEnv := os.Getenv("CONFIG")
+
+	var configPath string
+	if *configPtr != "" {
+		configPath = *configPtr
+	} else if configEnv != "" {
+		configPath = configEnv
+	} else {
 		configPath = "./config.toml"
 	}
 
+	log.Println("resolved config file", configPath)
+
 	cfg, err := config.Load(configPath)
 	if err != nil {
 		panic(err)