Prevent composed post data loss when posting fails

Keeps temporary post file around until a post successfully goes through.

writeas/cli.go

@@ -3,6 +3,7 @@ package main
 import (
 	"bufio"
 	"bytes"
+	"errors"
 	"fmt"
 	"github.com/codegangsta/cli"
 	"io"
@@ -201,7 +202,7 @@ func check(err error) {
 	}
 }
 
-func handlePost(fullPost []byte, c *cli.Context) {
+func handlePost(fullPost []byte, c *cli.Context) error {
 	tor := c.Bool("tor") || c.Bool("t")
 	if c.Int("tor-port") != 0 {
 		torPort = c.Int("tor-port")
@@ -212,15 +213,16 @@ func handlePost(fullPost []byte, c *cli.Context) {
 		fmt.Println("Posting...")
 	}
 
-	DoPost(fullPost, false, tor, c.Bool("code"))
+	return DoPost(fullPost, false, tor, c.Bool("code"))
 }
 
 func cmdPost(c *cli.Context) {
-	handlePost(readStdIn(), c)
+	err := handlePost(readStdIn(), c)
+	check(err)
 }
 
 func cmdNew(c *cli.Context) {
-	p := composeNewPost()
+	fname, p := composeNewPost()
 	if p == nil {
 		// Assume composeNewPost already told us what the error was. Abort now.
 		os.Exit(1)
@@ -228,11 +230,26 @@ func cmdNew(c *cli.Context) {
 
 	// Ensure we have something to post
 	if len(*p) == 0 {
+		// Clean up temporary post
+		if fname != "" {
+			os.Remove(fname)
+		}
+
 		fmt.Println("Empty post. Bye!")
 		os.Exit(0)
 	}
 
-	handlePost(*p, c)
+	err := handlePost(*p, c)
+	if err != nil {
+		fmt.Printf("Error posting: %s\n", err)
+		fmt.Println(messageRetryCompose(fname))
+		os.Exit(1)
+	}
+
+	// Clean up temporary post
+	if fname != "" {
+		os.Remove(fname)
+	}
 }
 
 func cmdDelete(c *cli.Context) {
@@ -387,7 +404,7 @@ func DoFetch(friendlyId string, tor bool) {
 	}
 }
 
-func DoPost(post []byte, encrypt, tor, code bool) {
+func DoPost(post []byte, encrypt, tor, code bool) error {
 	data := url.Values{}
 	data.Set("w", string(post))
 	if encrypt {
@@ -407,12 +424,16 @@ func DoPost(post []byte, encrypt, tor, code bool) {
 	r.Header.Add("Content-Length", strconv.Itoa(len(data.Encode())))
 
 	resp, err := client.Do(r)
-	check(err)
+	if err != nil {
+		return err
+	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode == http.StatusOK {
 		content, err := ioutil.ReadAll(resp.Body)
-		check(err)
+		if err != nil {
+			return err
+		}
 
 		nlPos := strings.Index(string(content), "\n")
 		url := content[:nlPos]
@@ -424,8 +445,10 @@ func DoPost(post []byte, encrypt, tor, code bool) {
 
 		fmt.Printf("%s\n", url)
 	} else {
-		fmt.Printf("Unable to post: %s\n", resp.Status)
+		return errors.New(fmt.Sprintf("Unable to post: %s", resp.Status))
 	}
+
+	return nil
 }
 
 func DoUpdate(post []byte, friendlyId, token string, tor bool) {

writeas/posts.go

@@ -98,41 +98,47 @@ func getPosts() *[]Post {
 	return &posts
 }
 
-func composeNewPost() *[]byte {
+func composeNewPost() (string, *[]byte) {
 	f, err := fileutils.TempFile(os.TempDir(), "WApost", "txt")
 	if err != nil {
 		if DEBUG {
 			panic(err)
 		} else {
 			fmt.Printf("Error creating temp file: %s\n", err)
-			return nil
+			return "", nil
 		}
 	}
-	defer os.Remove(f.Name())
 	f.Close()
 
 	cmd := editPostCmd(f.Name())
 	if cmd == nil {
+		os.Remove(f.Name())
+
 		fmt.Println(NO_EDITOR_ERR)
-		return nil
+		return "", nil
 	}
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
 	if err := cmd.Start(); err != nil {
+		os.Remove(f.Name())
+
 		if DEBUG {
 			panic(err)
 		} else {
 			fmt.Printf("Error starting editor: %s\n", err)
-			return nil
+			return "", nil
 		}
 	}
+
+	// If something fails past this point, the temporary post file won't be
+	// removed automatically. Calling function should handle this.
 	if err := cmd.Wait(); err != nil {
 		if DEBUG {
 			panic(err)
 		} else {
 			fmt.Printf("Editor finished with error: %s\n", err)
-			return nil
+			return "", nil
 		}
 	}
 
@@ -142,8 +148,8 @@ func composeNewPost() *[]byte {
 			panic(err)
 		} else {
 			fmt.Printf("Error reading post: %s\n", err)
-			return nil
+			return "", nil
 		}
 	}
-	return &post
+	return f.Name(), &post
 }

writeas/posts_nix.go

@@ -38,3 +38,7 @@ func editPostCmd(fname string) *exec.Cmd {
 	}
 	return exec.Command(editor, fname)
 }
+
+func messageRetryCompose(fname string) string {
+	return fmt.Sprintf("To retry this post, run:\n  cat %s | writeas", fname)
+}

writeas/posts_win.go

@@ -20,3 +20,7 @@ func editPostCmd(fname string) *exec.Cmd {
 	// NOTE this won't work if fname contains spaces.
 	return exec.Command("cmd", "/C start /WAIT "+fname)
 }
+
+func messageRetryCompose(fname string) string {
+	return fmt.Sprintf("To retry this post, run:\n  type %s | writeas.exe", fname)
+}