more code review

Author: kensmith

fastmask/auth.go

@@ -16,7 +16,11 @@ func Authenticate(httpClient *http.Client, token SecureToken) (fastmailIdentity
 	req.Header.Set(_authHeader, "Bearer "+token.FullToken())
 
 	resp, err := httpClient.Do(req)
-	if err != nil || resp == nil {
+	if err != nil {
+		return
+	}
+	if resp == nil {
+		err = fmt.Errorf("strangely nil resp despite err being nil")
 		return
 	}
 	defer func() {

fastmask/const.go

@@ -18,4 +18,5 @@ const (
 	_maskedEmailSetMethod   = "MaskedEmail/set"
 	_prefixLen              = 5
 	_primaryAccountKey      = "urn:ietf:params:jmap:core"
+	_programName            = "fastmask"
 )

fastmask/fastmail.go

@@ -47,7 +47,11 @@ func CreateMaskedEmail(httpClient *http.Client, fastmailId *FastmailIdentity, do
 	req.Header.Set(_contentTypeHeader, _jsonContentType)
 	req.Header.Set(_authHeader, "Bearer "+token.FullToken())
 	resp, err := httpClient.Do(req)
-	if err != nil || resp == nil {
+	if err != nil {
+		return
+	}
+	if resp == nil {
+		err = fmt.Errorf("strangely nil resp despite err being nil")
 		return
 	}
 	defer func() {
@@ -59,8 +63,10 @@ func CreateMaskedEmail(httpClient *http.Client, fastmailId *FastmailIdentity, do
 
 	bodyBytes, err := io.ReadAll(resp.Body)
 	if err != nil {
+		err = fmt.Errorf("failed to read response body %d: %w", resp.StatusCode, err)
 		return
 	}
+
 	if resp.StatusCode != 200 {
 		body := string(bodyBytes)
 		err = fmt.Errorf("server returned status code %d: %s", resp.StatusCode, body)

fastmask/main.go

@@ -16,7 +16,7 @@ func usage(programName string) {
 
 func main() {
 	if len(os.Args) != 2 {
-		programName := "fastmask"
+		programName := _programName
 		if len(os.Args) > 0 {
 			programName = os.Args[0]
 		}

fastmask/prefix.go

@@ -8,15 +8,16 @@ var (
 )
 
 func GenPrefix() string {
-	randomBytes := make([]byte, _prefixLen)
+	prefixLen := max(1, _prefixLen)
+	randomBytes := make([]byte, prefixLen)
 	_, err := rand.Read(randomBytes)
 	if err != nil {
 		// the docs say this should never happen so it's acceptable to panic in
 		// this case rather than return an error to the caller
 		// https://pkg.go.dev/crypto/rand#Read
 		panic("failed to generate prefix")
 	}
-	for i := range _prefixLen {
+	for i := range prefixLen {
 		randByte := randomBytes[i]
 		lexeme := _lexicon[int(randByte)%_numLexemes]
 		randomBytes[i] = lexeme