Add cli-config.env file supporthalibut_7.90.0halibut/7.90.07.90.0

XDS environment configuration can be set using various methods.
Here is the list of various methods, ordered by priority:

 1/ from command line option: "--config myConfig.json"
 2/ from environment variable XDS_CONFIG
 3/ $HOME/.xds/cli/cli-config.env file
 4/ /etc/xds/cli/cli-config.env file

Change-Id: I1b59c05e583336fe05459de91a35d47cf5ddf670
Signed-off-by: Sebastien Douheret <sebastien.douheret@iot.bzh>

1 files changed, 30 insertions, 15 deletions

diff --git a/main.go b/main.go
index 9ac751c..c28e1be 100644
--- a/main.go
+++ b/main.go
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2017-2018 "IoT.bzh"
+ * Copyright (C) 2017-2019 "IoT.bzh"
  * Author Sebastien Douheret <sebastien@iot.bzh>
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -23,6 +23,7 @@ package main
 import (
 	"fmt"
 	"os"
+	"path"
 	"regexp"
 	"sort"
 	"strings"
@@ -57,8 +58,9 @@ var AppSubVersion = "unknown-dev"
 
 // Application details
 const (
-	appCopyright    = "Copyright (C) 2017-2018 IoT.bzh - Apache-2.0"
-	defaultLogLevel = "error"
+	appCopyright             = "Copyright (C) 2017-2019 IoT.bzh - Apache-2.0"
+	defaultLogLevel          = "error"
+	defaultConfigEnvFilename = "cli-config.env"
 )
 
 // Log Global variable that hold logger
@@ -240,27 +242,40 @@ func main() {
 
 	// Early and manual processing of --config option in order to set XDS_xxx
 	// variables before parsing of option by app cli
-	confFile := os.Getenv("XDS_CONFIG")
+	//  1/ from command line option: "--config myConfig.json"
+	//  2/ from environment variable XDS_CONFIG
+	//  3/ $HOME/.xds/cli/cli-config.env file
+	//  4/ /etc/xds/cli/cli-config.env file
+	searchIn := make([]string, 0, 4)
 	for idx, a := range os.Args[1:] {
 		if a == "-c" || a == "--config" || a == "-config" {
-			confFile = os.Args[idx+2]
+			searchIn = append(searchIn, os.Args[idx+2])
 			break
 		}
 	}
+	searchIn = append(searchIn, os.Getenv("XDS_CONFIG"))
+	if usrHome := common.GetUserHome(); usrHome != "" {
+		searchIn = append(searchIn, path.Join(usrHome, ".xds", "cli", defaultConfigEnvFilename))
+	}
+	searchIn = append(searchIn, path.Join("/etc", "xds", "cli", defaultConfigEnvFilename))
+
+	// Use the first existing env config file
+	confFile := ""
+	for _, p := range searchIn {
+		if pr, err := common.ResolveEnvVar(p); err == nil {
+			earlyPrintf("Check if confFile exists : %v", pr)
+			if common.Exists(pr) {
+				confFile = pr
+				break
+			}
+		}
+	}
 
 	// Load config file if requested
 	if confFile != "" {
-		earlyPrintf("confFile detected: %v", confFile)
-		confFile, err := common.ResolveEnvVar(confFile)
-		if err != nil {
-			exitError(1, "Error while resolving confFile: %v", err)
-		}
-		earlyPrintf("Resolved confFile: %v", confFile)
-		if !common.Exists(confFile) {
-			exitError(1, "Error env config file not found")
-		}
+		earlyPrintf("Used confFile: %v", confFile)
 		// Load config file variables that will overwrite env variables
-		err = godotenv.Overload(confFile)
+		err := godotenv.Overload(confFile)
 		if err != nil {
 			exitError(1, "Error loading env config file "+confFile)
 		}