Typed error for Not Found (404) responses

client.go

@@ -138,7 +138,12 @@ func (c *Client) request(method, requestPath string, query url.Values, body []by
 	}
 
 	// check status code.
-	if resp.StatusCode >= 400 {
+	switch {
+	case resp.StatusCode == http.StatusNotFound:
+		return ErrNotFound{
+			BodyContents: bodyContents,
+		}
+	case resp.StatusCode >= 400:
 		return fmt.Errorf("status: %d, body: %v", resp.StatusCode, string(bodyContents))
 	}
 

errors.go

@@ -0,0 +1,11 @@
+package gapi
+
+import "fmt"
+
+type ErrNotFound struct {
+	BodyContents []byte
+}
+
+func (e ErrNotFound) Error() string {
+	return fmt.Sprintf("status: 404, body: %s", e.BodyContents)
+}