fix: handle buildUrl errors gracefully (#143)

Author: kpritam

client/request_handler.go

@@ -24,12 +24,20 @@ func NewRequestHandler(client BaseClient) *RequestHandler {
 
 func (c *RequestHandler) sendRequest(method string, rawURL string, data url.Values,
 	headers map[string]interface{}) (*http.Response, error) {
-	return c.Client.SendRequest(method, c.BuildUrl(rawURL), data, headers)
+	parsedURL, err := c.BuildUrl(rawURL)
+	if err != nil {
+		return nil, err
+	}
+
+	return c.Client.SendRequest(method, parsedURL, data, headers)
 }
 
 // BuildUrl builds the target host string taking into account region and edge configurations.
-func (c *RequestHandler) BuildUrl(rawURL string) string {
-	u, _ := url.Parse(rawURL)
+func (c *RequestHandler) BuildUrl(rawURL string) (string, error) {
+	u, err := url.Parse(rawURL)
+	if err != nil {
+		return "", err
+	}
 
 	var (
 		edge    = ""
@@ -43,7 +51,7 @@ func (c *RequestHandler) BuildUrl(rawURL string) string {
 	if len(pieces) >= 3 {
 		suffix = strings.Join(pieces[len(pieces)-2:], ".")
 	} else {
-		return u.String()
+		return u.String(), nil
 	}
 
 	if len(pieces) == 4 {
@@ -72,7 +80,7 @@ func (c *RequestHandler) BuildUrl(rawURL string) string {
 	}
 
 	u.Host = strings.Join(result, ".")
-	return u.String()
+	return u.String(), nil
 }
 
 func (c *RequestHandler) Post(path string, bodyData url.Values, headers map[string]interface{}) (*http.Response, error) {

client/request_handler_test.go

@@ -1,6 +1,8 @@
 package client_test
 
 import (
+	"errors"
+	"net/url"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -15,35 +17,51 @@ func NewRequestHandler(accountSid string, authToken string) *client.RequestHandl
 func TestRequestHandler_BuildUrlSetRegion(t *testing.T) {
 	// Region set via url
 	requestHandler := NewRequestHandler("user", "pass")
-	assert.Equal(t, "https://api.region.twilio.com", requestHandler.BuildUrl("https://api.region.twilio.com"))
+	assert.Equal(t, "https://api.region.twilio.com", assertAndGetURL(t, requestHandler, "https://api.region.twilio.com"))
 
 	// Region set via requestHandler
 	requestHandler.Region = "region"
-	assert.Equal(t, "https://api.region.twilio.com", requestHandler.BuildUrl("https://api.twilio.com"))
-	assert.Equal(t, "https://api.region.twilio.com", requestHandler.BuildUrl("https://api.urlRegion.twilio.com"))
+	assert.Equal(t, "https://api.region.twilio.com", assertAndGetURL(t, requestHandler, "https://api.twilio.com"))
+	assert.Equal(t, "https://api.region.twilio.com", assertAndGetURL(t, requestHandler, "https://api.urlRegion.twilio.com"))
 }
 
 func TestRequestHandler_BuildUrlSetEdgeDefaultRegion(t *testing.T) {
 	// Edge set via client
 	requestHandler := NewRequestHandler("user", "pass")
 	requestHandler.Edge = "edge"
-	assert.Equal(t, "https://api.edge.us1.twilio.com", requestHandler.BuildUrl("https://api.twilio.com"))
+	assert.Equal(t, "https://api.edge.us1.twilio.com", assertAndGetURL(t, requestHandler, "https://api.twilio.com"))
 }
 
 func TestRequestHandler_BuildUrlSetEdgeRegion(t *testing.T) {
 	//Edge and Region set via url
 	requestHandler := NewRequestHandler("user", "pass")
-	assert.Equal(t, "https://api.edge.region.twilio.com", requestHandler.BuildUrl("https://api.edge.region.twilio.com"))
+	assert.Equal(t, "https://api.edge.region.twilio.com", assertAndGetURL(t, requestHandler, "https://api.edge.region.twilio.com"))
 
 	// Edge and Region set via client
 	requestHandler.Edge = "edge"
-	assert.Equal(t, "https://api.edge.region.twilio.com", requestHandler.BuildUrl("https://api.region.twilio.com"))
+	assert.Equal(t, "https://api.edge.region.twilio.com", assertAndGetURL(t, requestHandler, "https://api.region.twilio.com"))
 	requestHandler.Region = "region"
-	assert.Equal(t, "https://api.edge.region.twilio.com", requestHandler.BuildUrl("https://api.twilio.com"))
-	assert.Equal(t, "https://api.edge.region.twilio.com", requestHandler.BuildUrl("https://api.urlEdge.urlRegion.twilio.com"))
+	assert.Equal(t, "https://api.edge.region.twilio.com", assertAndGetURL(t, requestHandler, "https://api.twilio.com"))
+	assert.Equal(t, "https://api.edge.region.twilio.com", assertAndGetURL(t, requestHandler, "https://api.urlEdge.urlRegion.twilio.com"))
 }
 
 func TestRequestHandler_BuildHostRawHostWithoutPeriods(t *testing.T) {
 	requestHandler := NewRequestHandler("user", "pass")
-	assert.Equal(t, "https://prism_twilio:4010", requestHandler.BuildUrl("https://prism_twilio:4010"))
+	assert.Equal(t, "https://prism_twilio:4010", assertAndGetURL(t, requestHandler, "https://prism_twilio:4010"))
+}
+
+func TestRequestHandler_BuildUrlInvalidCTLCharacter(t *testing.T) {
+	requestHandler := NewRequestHandler("user", "pass")
+	rawURL := "https://api.twilio.com/ServiceId\n"
+	parsedURL, err := requestHandler.BuildUrl(rawURL)
+	
+	expectedErr := url.Error{Op: "parse", URL: rawURL, Err: errors.New("net/url: invalid control character in URL")}
+	assert.Equal(t, &expectedErr, err)
+	assert.Equal(t, parsedURL, "")
+}
+
+func assertAndGetURL(t *testing.T, requestHandler *client.RequestHandler, rawURL string) string {
+	parsedURL, err := requestHandler.BuildUrl(rawURL)
+	assert.Nil(t, err)
+	return parsedURL
 }