TUN-1099: Bring back changes in 2018.10.1

cmd/cloudflared/config/configuration.go

@@ -0,0 +1,62 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+
+	homedir "github.com/mitchellh/go-homedir"
+	"gopkg.in/urfave/cli.v2"
+	"gopkg.in/urfave/cli.v2/altsrc"
+)
+
+var (
+	// File names from which we attempt to read configuration.
+	DefaultConfigFiles = []string{"config.yml", "config.yaml"}
+
+	// Launchd doesn't set root env variables, so there is default
+	// Windows default config dir was ~/cloudflare-warp in documentation; let's keep it compatible
+	DefaultConfigDirs = []string{"~/.cloudflared", "~/.cloudflare-warp", "~/cloudflare-warp", "/usr/local/etc/cloudflared", "/etc/cloudflared"}
+)
+
+const DefaultCredentialFile = "cert.pem"
+
+// FileExists checks to see if a file exist at the provided path.
+func FileExists(path string) (bool, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			// ignore missing files
+			return false, nil
+		}
+		return false, err
+	}
+	f.Close()
+	return true, nil
+}
+
+// FindInputSourceContext pulls the input source from the config flag.
+func FindInputSourceContext(context *cli.Context) (altsrc.InputSourceContext, error) {
+	if context.String("config") != "" {
+		return altsrc.NewYamlSourceFromFile(context.String("config"))
+	}
+	return nil, nil
+}
+
+// FindDefaultConfigPath returns the first path that contains a config file.
+// If none of the combination of DefaultConfigDirs and DefaultConfigFiles
+// contains a config file, return empty string.
+func FindDefaultConfigPath() string {
+	for _, configDir := range DefaultConfigDirs {
+		for _, configFile := range DefaultConfigFiles {
+			dirPath, err := homedir.Expand(configDir)
+			if err != nil {
+				continue
+			}
+			path := filepath.Join(dirPath, configFile)
+			if ok, _ := FileExists(path); ok {
+				return path
+			}
+		}
+	}
+	return ""
+}