Add --env-file param and improve overall env-var loading

pkg/cli/env.go

@@ -0,0 +1,41 @@
+package cli
+
+import (
+	"os"
+	"path"
+	"sort"
+
+	"github.com/joho/godotenv"
+	"github.com/spf13/cobra"
+)
+
+// LoadEnv loads env-variables (KEY=VAL) from provided files and paths (by searching for .env file in the given path)
+//
+// Please not that loaded values DO NOT OVERRIDE the existing environmental variables
+func LoadEnv(pp ...string) error {
+	// preparse the input and try to figure out if .env should be appended
+	for i, p := range pp {
+		if s, err := os.Stat(p); err != nil {
+			return err
+		} else if s.IsDir() {
+			pp[i] = path.Join(p, ".env")
+		}
+	}
+
+	return godotenv.Load(pp...)
+}
+
+// EnvCommand outputs all loaded env variables
+func EnvCommand() *cobra.Command {
+	return &cobra.Command{
+		Use:  "env",
+		Long: "Outputs list (sorted by key) of of all environmental variables. Can be used for diagnosis and debugging",
+		Run: func(cmd *cobra.Command, args []string) {
+			kv := os.Environ()
+			sort.Strings(kv)
+			for _, l := range kv {
+				cmd.Println(l)
+			}
+		},
+	}
+}