Support custom env var GitHub Token name

Signed-off-by: KeisukeYamashita <[email protected]>

notifier/github/client.go

@@ -69,10 +69,11 @@ type service struct {
 // NewClient returns Client initialized with Config
 func NewClient(cfg Config) (*Client, error) {
 	token := cfg.Token
-	token = strings.TrimPrefix(token, "$")
-	if token == EnvToken {
-		token = os.Getenv(EnvToken)
+
+	if strings.HasPrefix(token, "$") {
+		token = os.Getenv(strings.TrimPrefix(token, "$"))
 	}
+
 	if token == "" {
 		return &Client{}, errors.New("github token is missing")
 	}

notifier/github/client_test.go

@@ -2,6 +2,7 @@ package github
 
 import (
 	"os"
+	"strings"
 	"testing"
 )
 
@@ -41,12 +42,24 @@ func TestNewClient(t *testing.T) {
 			envToken: "",
 			expect:   "github token is missing",
 		},
+		{
+			// specify via env but not to be set env (part 3)
+			config:   Config{Token: "$TFNOTIFY_GITHUB_TOKEN"},
+			envToken: "",
+			expect:   "github token is missing",
+		},
 		{
 			// specify via env (part 2)
 			config:   Config{Token: "$GITHUB_TOKEN"},
 			envToken: "abcdefg",
 			expect:   "",
 		},
+		{
+			// specify via env (part 3)
+			config:   Config{Token: "$TFNOTIFY_GITHUB_TOKEN"},
+			envToken: "abcdefg",
+			expect:   "",
+		},
 		{
 			// no specification (part 1)
 			config:   Config{},
@@ -61,7 +74,10 @@ func TestNewClient(t *testing.T) {
 		},
 	}
 	for _, testCase := range testCases {
-		os.Setenv(EnvToken, testCase.envToken)
+		if strings.HasPrefix(testCase.config.Token, "$") {
+			key := strings.TrimPrefix(testCase.config.Token, "$")
+			os.Setenv(key, testCase.envToken)
+		}
 		_, err := NewClient(testCase.config)
 		if err == nil {
 			continue