add web gui

cmd/web/server/config/config.go

@@ -0,0 +1,40 @@
+package config
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+)
+
+type (
+	Configuration struct {
+		Server ServerConfiguration `json:"server"`
+		Remote RemoteConfiguration `json:"remote"`
+	}
+
+	ServerConfiguration struct {
+		Port int `json:"port"`
+	}
+
+	RemoteConfiguration struct {
+		URL string `json:"url"`
+	}
+)
+
+func Load(path string) (Configuration, error) {
+	f, err := os.OpenFile(path, os.O_RDONLY, 0)
+	if err != nil {
+		return Configuration{}, fmt.Errorf("failed to open configuration file: %w", err)
+	}
+	defer f.Close()
+
+	d := json.NewDecoder(f)
+
+	var c Configuration
+	err = d.Decode(&c)
+	if err != nil {
+		return Configuration{}, fmt.Errorf("failed to parse configuration file (%s): %w", path, err)
+	}
+
+	return c, nil
+}