Add travis.yml

.travis.yml

@@ -0,0 +1,18 @@
+sudo: false
+
+language: go
+
+go:
+  - 1.9.x
+  - tip
+
+services:
+  - docker
+
+notifications:
+  email:
+    on_success: never
+    on_failure: always
+
+script:
+  - go build .

README.md

@@ -1,10 +1,37 @@
-# google-id-token
-Google ID token
+## google-id-token
 
+A small application to retrieve or verify google ID token
 
-## Acquire new user credentials
+[![Build Status](https://travis-ci.org/grepplabs/google-id-token.svg?branch=master)](https://travis-ci.org/grepplabs/google-id-token)
+
+### Building
+
+	go build
+
+### Help output
+
+    Retrieve or verify google ID token
+
+    Usage:
+      google-id-token [flags]
+      google-id-token [command]
+
+    Available Commands:
+      get         get cached or new token
+      help        Help about any command
+      new         get a new token
+      print       print the decoded token
+      verify      verify the token
+
+    Flags:
+          --client-id string   Client ID (optional)
+      -h, --help               help for google-id-token
+      -t, --timeout int        Timeout in seconds (default 5)
+
+
+### Acquire new user credentials and oogle ID token
 [Application Default Credentials](https://cloud.google.com/sdk/gcloud/reference/auth/application-default/login)
 
-```bash
-gcloud auth application-default login
-``` 
+    gcloud auth application-default login
+    google-id-token new
+    google-id-token verify --id-token="$(google-id-token get)"

pkg/token/token_verifier.go

@@ -37,6 +37,10 @@ func (v *Verifier) VerifyIDToken(ctx context.Context, jwt string, audience strin
 }
 
 func (v *Verifier) verifyIDToken(jwt string, audience string, certs *certs) error {
+	if jwt == "" {
+		return errors.New("token is empty")
+	}
+
 	header, payload, signature, checksum, err := v.splitToken(jwt)
 	if err != nil {
 		return err