Merge pull request #105 from github/credentials-env-variables

config file supports environment variables

Author: Shlomi Noach

build.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 #
-RELEASE_VERSION="1.0.3"
+RELEASE_VERSION="1.0.4"
 
 buildpath=/tmp/gh-ost
 target=gh-ost

go/base/context.go

@@ -7,6 +7,8 @@ package base
 
 import (
 	"fmt"
+	"os"
+	"regexp"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -35,6 +37,10 @@ const (
 	CutOverTwoStep         = iota
 )
 
+var (
+	envVariableRegexp = regexp.MustCompile("[$][{](.*)[}]")
+)
+
 // MigrationContext has the general, global state of migration. It is used by
 // all components throughout the migration process.
 type MigrationContext struct {
@@ -441,8 +447,19 @@ func (this *MigrationContext) ReadConfigFile() error {
 	if this.ConfigFile == "" {
 		return nil
 	}
+	gcfg.RelaxedParserMode = true
 	if err := gcfg.ReadFileInto(&this.config, this.ConfigFile); err != nil {
 		return err
 	}
+
+	// We accept user & password in the form "${SOME_ENV_VARIABLE}" in which case we pull
+	// the given variable from os env
+	if submatch := envVariableRegexp.FindStringSubmatch(this.config.Client.User); len(submatch) > 1 {
+		this.config.Client.User = os.Getenv(submatch[1])
+	}
+	if submatch := envVariableRegexp.FindStringSubmatch(this.config.Client.Password); len(submatch) > 1 {
+		this.config.Client.Password = os.Getenv(submatch[1])
+	}
+
 	return nil
 }