Add client docs, test

2 files changed, 26 insertions, 1 deletions

diff --git a/client/client.go b/client/client.go
index e39a6a1..af7c2d8 100644
--- a/client/client.go
+++ b/client/client.go
@@ -1,3 +1,5 @@
+// Package client makes requests to a Caesar Cipher Server in order to encode
+// and decode messages.
 package client
 
 import (
@@ -9,14 +11,20 @@ import (
 	"time"
 )
 
+// A CaesarClient handles communication with a server
 type CaesarClient struct {
+	// Endpoint is the URL to which HTTP requests should be made
 	Endpoint string
-	Token    string
+
+	// Token is an authorization token to supply to the server
+	Token string
 
 	c    *http.Client
 	once sync.Once
 }
 
+// EncodeMessage asks the Caesar server to encode the supplied message and
+// returns the result along with an error in case the request fails.
 func (c *CaesarClient) EncodeMessage(r io.Reader) (io.Reader, error) {
 	c.once.Do(func() {
 		c.c = &http.Client{Timeout: 10 * time.Second}
diff --git a/client/client_test.go b/client/client_test.go
index b4a1b2a..9ccc149 100644
--- a/client/client_test.go
+++ b/client/client_test.go
@@ -64,3 +64,20 @@ func TestEncode(t *testing.T) {
 		t.Errorf("expected 'response' but got '%s'", resp)
 	}
 }
+
+func TestUserAgent(t *testing.T) {
+	var ua string
+	var hf http.HandlerFunc = func(w http.ResponseWriter, r *http.Request) {
+		ua = r.Header.Get("user-agent")
+	}
+	server := httptest.NewServer(hf)
+	defer server.Close()
+
+	c := CaesarClient{Endpoint: server.URL}
+	c.EncodeMessage(strings.NewReader("secret message"))
+
+	expected := "caesar-client/1.0"
+	if ua != expected {
+		t.Errorf("expected user agent header %q but got %q", expected, ua)
+	}
+}