Use error constants for some httpz error cases

httpx/access_test.go

@@ -35,41 +35,37 @@ func TestAccessConfig(t *testing.T) {
 	}))
 
 	tests := []struct {
-		url string
-		err string
+		url     string
+		allowed bool
 	}{
 		// allowed
-		{"https://nyaruka.com", ""},
-		{"https://11.0.0.0", ""},
+		{"https://nyaruka.com", true},
+		{"https://11.0.0.0", true},
 
 		// denied by IP match
-		{"https://localhost/path", "request to localhost denied"},
-		{"https://LOCALHOST:80", "request to LOCALHOST denied"},
-		{"http://foo.localtest.me", "request to foo.localtest.me denied"},
-		{"https://127.0.0.1", "request to 127.0.0.1 denied"},
-		{"https://127.0.00.1", "?"}, // Go 1.19: "request to 127.0.00.1 denied", Go 1.20: "lookup 127.0.00.1: no such host"
-		{"https://[::1]:80", "request to ::1 denied"},
-		{"https://[0:0:0:0:0:0:0:1]:80", "request to 0:0:0:0:0:0:0:1 denied"},
-		{"https://[0000:0000:0000:0000:0000:0000:0000:0001]:80", "request to 0000:0000:0000:0000:0000:0000:0000:0001 denied"},
+		{"https://localhost/path", false},
+		{"https://LOCALHOST:80", false},
+		{"http://foo.localtest.me", false},
+		{"https://127.0.0.1", false},
+		{"https://127.0.00.1", false},
+		{"https://[::1]:80", false},
+		{"https://[0:0:0:0:0:0:0:1]:80", false},
+		{"https://[0000:0000:0000:0000:0000:0000:0000:0001]:80", false},
 
 		// denied by network match
-		{"https://10.1.0.0", "request to 10.1.0.0 denied"},
-		{"https://10.0.1.0", "request to 10.0.1.0 denied"},
-		{"https://10.0.0.1", "request to 10.0.0.1 denied"},
-		{"https://[0:0:0:0:0:ffff:0a01:0000]:80", "request to 0:0:0:0:0:ffff:0a01:0000 denied"}, // 10.1.0.0 mapped to IPv6
+		{"https://10.1.0.0", false},
+		{"https://10.0.1.0", false},
+		{"https://10.0.0.1", false},
+		{"https://[0:0:0:0:0:ffff:0a01:0000]:80", false}, // 10.1.0.0 mapped to IPv6
 	}
 	for _, tc := range tests {
 		request, _ := http.NewRequest("GET", tc.url, nil)
 		_, err := httpx.DoTrace(http.DefaultClient, request, nil, access, -1)
 
-		if tc.err != "" {
-			if tc.err == "?" {
-				assert.Error(t, err)
-			} else {
-				assert.EqualError(t, err, tc.err, "error message mismatch for url %s", tc.url)
-			}
-		} else {
+		if tc.allowed {
 			assert.NoError(t, err)
+		} else {
+			assert.Equal(t, err, httpx.ErrAccessConfig, "error message mismatch for url %s", tc.url)
 		}
 	}
 }

httpx/http.go

@@ -16,6 +16,12 @@ import (
 	"github.com/pkg/errors"
 )
 
+// ErrResponseSize is returned when response size exceeds provided limit
+var ErrResponseSize = errors.New("response body exceeds size limit")
+
+// ErrAccessConfig is returned when provided access config prevents request
+var ErrAccessConfig = errors.New("request not permitted by access config")
+
 // Do makes the given HTTP request using the current requestor and retry config
 func Do(client *http.Client, request *http.Request, retries *RetryConfig, access *AccessConfig) (*http.Response, error) {
 	r, _, err := do(client, request, retries, access)
@@ -29,7 +35,7 @@ func do(client *http.Client, request *http.Request, retries *RetryConfig, access
 			return nil, 0, err
 		}
 		if !allowed {
-			return nil, 0, errors.Errorf("request to %s denied", request.URL.Hostname())
+			return nil, 0, ErrAccessConfig
 		}
 	}
 
@@ -198,7 +204,7 @@ func readBody(response *http.Response, maxBodyBytes int) ([]byte, error) {
 
 		// if we have no remaining bytes, error because the body was too big
 		if bodyReader.(*io.LimitedReader).N <= 0 {
-			return nil, errors.Errorf("webhook response body exceeds %d bytes limit", maxBodyBytes)
+			return nil, ErrResponseSize
 		}
 
 		return bodyBytes, nil

httpx/http_test.go

@@ -157,7 +157,8 @@ func TestMaxBodyBytes(t *testing.T) {
 	assert.Equal(t, string(testBody), string(trace.ResponseBody))
 
 	trace, err = call(10) // limit smaller than body
-	assert.EqualError(t, err, `webhook response body exceeds 10 bytes limit`)
+	assert.Equal(t, err, httpx.ErrResponseSize)
+	assert.EqualError(t, err, `response body exceeds size limit`)
 	assert.Equal(t, "HTTP/1.0 200 OK\r\nContent-Length: 26\r\n\r\n", string(trace.ResponseTrace))
 	assert.Equal(t, ``, string(trace.ResponseBody))
 }