Improve error handling.

cli/util.go

@@ -38,7 +38,10 @@ func instantiate(config *Config) {
 	fmt.Printf("Connecting to %s.", config.Server)
 	conn := irc.New(config.UserName, config.Version)
 	config.irc = conn
-	core.Join(conn, config.Server)
+	err := core.Join(conn, config.Server)
+	if err != nil {
+		log.Fatal(err)
+	}
 	fmt.Printf("%sConnected to %s.\n", clearLine, config.Server)
 }
 

core/irchighway.go

@@ -11,12 +11,16 @@ import (
 // Specific irc.irchighway.net commands
 
 // Join connects to the irc.irchighway.net server and joins the #ebooks channel
-func Join(irc *irc.Conn, url string) {
-	irc.Connect(url)
+func Join(irc *irc.Conn, url string) error {
+	err := irc.Connect(url)
+	if err != nil {
+		return err
+	}
 	// Wait before joining the ebooks room
 	// Often you recieve a private message from the server
 	time.Sleep(time.Second * 2)
 	irc.JoinChannel("ebooks")
+	return nil
 }
 
 // SearchBook sends a search query to the search bot

core/search_parser.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"log"
 	"os"
 	"sort"
 	"strings"
@@ -64,14 +63,15 @@ func (p ParseError) String() string {
 }
 
 // ParseSearchFile converts a single search file into an array of BookDetail
-func ParseSearchFile(filePath string) ([]BookDetail, []ParseError) {
+func ParseSearchFile(filePath string) ([]BookDetail, []ParseError, error) {
 	file, err := os.Open(filePath)
 	if err != nil {
-		log.Fatal(err)
+		return nil, nil, err
 	}
 	defer file.Close()
 
-	return ParseSearchV2(file)
+	books, errs := ParseSearchV2(file)
+	return books, errs, nil
 }
 
 func ParseSearch(reader io.Reader) ([]BookDetail, []ParseError) {

dcc/dcc.go

@@ -4,7 +4,6 @@ import (
 	"encoding/binary"
 	"errors"
 	"io"
-	"log"
 	"net"
 	"regexp"
 	"strconv"
@@ -76,13 +75,13 @@ func (download Download) Download(writer io.Writer) error {
 	bytes := make([]byte, 4096)
 	for int64(received) < download.Size {
 		n, err := conn.Read(bytes)
-
 		if err != nil {
-			log.Fatal("Error Downloading Data", err)
+			return err
 		}
+
 		_, err = writer.Write(bytes[:n])
 		if err != nil {
-			log.Println(err)
+			return err
 		}
 		received += n
 	}

irc/irc.go

@@ -1,7 +1,6 @@
 package irc
 
 import (
-	"log"
 	"net"
 )
 
@@ -25,11 +24,10 @@ func New(username, realname string) *Conn {
 }
 
 // Connect connects to the given server at port 6667
-func (i *Conn) Connect(address string) {
+func (i *Conn) Connect(address string) error {
 	conn, err := net.Dial("tcp", address+":6667")
-
 	if err != nil {
-		log.Fatal("IRC Connection Error ", err)
+		return err
 	}
 
 	i.Conn = conn
@@ -39,40 +37,56 @@ func (i *Conn) Connect(address string) {
 
 	i.Write([]byte(user))
 	i.Write([]byte(nick))
+	return nil
 }
 
 // Disconnect closes connection to the IRC server
 func (i *Conn) Disconnect() {
+	if !i.IsConnected() {
+		return
+	}
 	i.Write([]byte("QUIT :Goodbye\r\n"))
 	i.Conn.Close()
 }
 
 // SendMessage sends the given message string to the connected IRC server
 func (i *Conn) SendMessage(message string) {
+	if !i.IsConnected() {
+		return
+	}
 	i.Write([]byte("PRIVMSG #" + i.channel + " :" + message + "\r\n"))
 }
 
 // SendNotice sends a notice message to the specified user
 func (i *Conn) SendNotice(user string, message string) {
+	if !i.IsConnected() {
+		return
+	}
 	i.Write([]byte("NOTICE " + user + " :" + message + "\r\n"))
 }
 
 // JoinChannel joins the channel given by channel string
 func (i *Conn) JoinChannel(channel string) {
-	i.channel = channel
-	_, err := i.Write([]byte("JOIN #" + channel + "\r\n"))
-	if err != nil {
-		log.Fatal(err)
+	if !i.IsConnected() {
+		return
 	}
+	i.channel = channel
+	i.Write([]byte("JOIN #" + channel + "\r\n"))
 }
 
 // GetUsers sends a NAMES request to the IRC server
 func (i *Conn) GetUsers(channel string) {
+	if !i.IsConnected() {
+		return
+	}
 	i.Write([]byte("NAMES #" + channel + "\r\n"))
 }
 
 // Pong sends a Pong message to the server, often used after a PING request
 func (i *Conn) Pong(server string) {
+	if !i.IsConnected() {
+		return
+	}
 	i.Write([]byte("PONG " + server + "\r\n"))
 }
 

server/irc_events.go

@@ -28,24 +28,32 @@ func (c *Client) searchResultHandler(downloadDir string) core.HandlerFunc {
 		extractedPath, err := core.DownloadExtractDCCString(filepath.Join(downloadDir, "books"), text, nil)
 		if err != nil {
 			c.log.Println(err)
+			c.send <- newErrorResponse("Error when downloading search results.")
+			return
 		}
 
-		results, errors := core.ParseSearchFile(extractedPath)
-		// Output all errors so parser can be improved over time
-		if len(errors) > 0 {
-			c.log.Printf("%d Search Result Parsing Errors\n", len(errors))
-			for _, err := range errors {
-				c.log.Println(err)
-			}
+		bookResults, parseErrors, err := core.ParseSearchFile(extractedPath)
+		if err != nil {
+			c.log.Println(err)
+			c.send <- newErrorResponse("Error when parsing search results.")
+			return
 		}
 
-		if len(results) == 0 && len(errors) == 0 {
+		if len(bookResults) == 0 && len(parseErrors) == 0 {
 			c.noResultsHandler(text)
 			return
 		}
 
-		c.log.Printf("Sending %d search results.\n", len(results))
-		c.send <- newSearchResponse(results, errors)
+		// Output all errors so parser can be improved over time
+		if len(parseErrors) > 0 {
+			c.log.Printf("%d Search Result Parsing Errors\n", len(parseErrors))
+			for _, err := range parseErrors {
+				c.log.Println(err)
+			}
+		}
+
+		c.log.Printf("Sending %d search results.\n", len(bookResults))
+		c.send <- newSearchResponse(bookResults, parseErrors)
 
 		err = os.Remove(extractedPath)
 		if err != nil {
@@ -60,8 +68,7 @@ func (c *Client) bookResultHandler(downloadDir string) core.HandlerFunc {
 		extractedPath, err := core.DownloadExtractDCCString(filepath.Join(downloadDir, "books"), text, nil)
 		if err != nil {
 			c.log.Println(err)
-
-			c.send <- newErrorResponse(err.Error())
+			c.send <- newErrorResponse("Error when downloading book.")
 			return
 		}
 

server/routes.go

@@ -95,7 +95,7 @@ func (server *server) staticFilesHandler(assetPath string) http.Handler {
 	// update the embedded file system's tree so that index.html is at the root
 	app, err := fs.Sub(reactClient, assetPath)
 	if err != nil {
-		server.log.Fatal(err)
+		server.log.Println(err)
 	}
 
 	// strip the predefined base path and serve the static file

server/websocket_requests.go

@@ -49,7 +49,13 @@ func (server *server) routeMessage(message Request, c *Client) {
 
 // handle ConnectionRequests and either connect to the server or do nothing
 func (c *Client) startIrcConnection(server *server) {
-	core.Join(c.irc, server.config.Server)
+	err := core.Join(c.irc, server.config.Server)
+	if err != nil {
+		c.log.Println(err)
+		c.send <- newErrorResponse("Unable to connect to IRC server.")
+		return
+	}
+
 	handler := server.NewIrcEventHandler(c)
 
 	if server.config.Log {