Merge pull request #1 from StevenMaude/refactor-and-tidy

Refactor and tidy

README.md

@@ -30,7 +30,6 @@ too often in a short time. See TODO.
 
 ## TODO:
 
-* Fix panics on no messages.
 * Consider introducing slight pauses between requests to try and
   improve reliability.
 * Possibly consider selecting other than latest message (though outside

main.go

@@ -51,14 +51,13 @@ type mail struct {
 	} `json:"data"`
 }
 
-// TODO: consider dropping most of this. Can get from the message itself.
+type publicMsg struct {
+	ID string `json:"id"`
+	To string `json:"to"`
+}
+
 type mailboxDetails struct {
-	PublicMsgs []struct {
-		FromFull string `json:"fromfull"`
-		Subject  string `json:"subject"`
-		ID       string `json:"id"`
-		To       string `json:"to"`
-	} `json:"public_msgs"`
+	PublicMsgs []publicMsg `json:"public_msgs"`
 }
 
 func getMailboxDetails(localPart string) (mailboxDetails, error) {
@@ -73,20 +72,12 @@ func getMailboxDetails(localPart string) (mailboxDetails, error) {
 
 	defer resp.Body.Close()
 	err = json.NewDecoder(resp.Body).Decode(&mbxDetails)
-	if err != nil {
-		return mbxDetails, err
-	}
+	// No need for error check here as we return mbxDetails and err whether
+	// we have an error or not.
 	return mbxDetails, err
 }
 
-func getCookies(mbxDetails mailboxDetails) ([]*http.Cookie, error) {
-	// TODO: consider allow to retrieve more than one message.
-	// TODO: fix panic on no messages.
-	// TODO: just pass in the single message; avoid duplication?
-	// TODO: confirm that first item is the latest message (but I think
-	// it is from previous testing of the bash script).
-	latestMsg := mbxDetails.PublicMsgs[0]
-
+func getCookies(latestMsg publicMsg) ([]*http.Cookie, error) {
 	// This request is for nothing but getting required cookies.
 	// Otherwise, the subsequent request fails.
 	inboxURL := "https://www.mailinator.com/inbox2.jsp?public_to=" + latestMsg.To
@@ -102,17 +93,13 @@ func getCookies(mbxDetails mailboxDetails) ([]*http.Cookie, error) {
 	return cookies, err
 }
 
-func getMail(mbxDetails mailboxDetails, cookies []*http.Cookie) error {
-	// TODO: consider allow to retrieve more than one message.
-	// TODO: fix panic on no messages.
-	// TODO: just pass in the single message; avoid duplication?
-	// TODO: confirm that first item is the latest message (but I think
-	// it is from previous testing of the bash script).
-	latestMsg := mbxDetails.PublicMsgs[0]
-
+func getMail(latestMsg publicMsg, cookies []*http.Cookie) error {
 	msgURL := "https://www.mailinator.com/fetchmail?msgid=" + latestMsg.ID + "&zone=public"
 	fmt.Println("Retrieving URL:", msgURL)
 	req, err := http.NewRequest("GET", msgURL, nil)
+	if err != nil {
+		return err
+	}
 
 	for _, c := range cookies {
 		req.AddCookie(c)
@@ -139,6 +126,7 @@ func getMail(mbxDetails mailboxDetails, cookies []*http.Cookie) error {
 }
 
 func main() {
+	// TODO: consider allow to retrieve more than one message.
 	if len(os.Args) != 2 {
 		fmt.Println("Usage: mailin8 <local-part>")
 		os.Exit(1)
@@ -151,13 +139,21 @@ func main() {
 		os.Exit(1)
 	}
 
-	cookies, err := getCookies(mbxDetails)
+	numberMsgs := len(mbxDetails.PublicMsgs)
+	if numberMsgs == 0 {
+		fmt.Println("no messages in inbox")
+		os.Exit(0)
+	}
+
+	latestMsg := mbxDetails.PublicMsgs[numberMsgs-1]
+
+	cookies, err := getCookies(latestMsg)
 	if err != nil {
 		fmt.Println("failed to get cookies:", err)
 		os.Exit(1)
 	}
 
-	err = getMail(mbxDetails, cookies)
+	err = getMail(latestMsg, cookies)
 	if err != nil {
 		fmt.Println("failed to get mail:", err)
 		os.Exit(1)