Added del and has and some helper functions

cmd/main.go

@@ -86,9 +86,27 @@ func main() {
 			Flags:  app.Flags,
 		},
 		{
-			Name: "fix",
+			Name: "del",
 			// Usage: "add a task to the list",
-			Action: hostess.Fix,
+			Action: hostess.Del,
+			Flags:  app.Flags,
+		},
+		{
+			Name: "has",
+			// Usage: "add a task to the list",
+			Action: hostess.Has,
+			Flags:  app.Flags,
+		},
+		{
+			Name: "off",
+			// Usage: "add a task to the list",
+			Action: hostess.Off,
+			Flags:  app.Flags,
+		},
+		{
+			Name: "on",
+			// Usage: "add a task to the list",
+			Action: hostess.On,
 			Flags:  app.Flags,
 		},
 		{
@@ -97,6 +115,24 @@ func main() {
 			Action: hostess.Ls,
 			Flags:  app.Flags,
 		},
+		{
+			Name: "fix",
+			// Usage: "add a task to the list",
+			Action: hostess.Fix,
+			Flags:  app.Flags,
+		},
+		{
+			Name: "dump",
+			// Usage: "add a task to the list",
+			Action: hostess.Dump,
+			Flags:  app.Flags,
+		},
+		{
+			Name: "apply",
+			// Usage: "add a task to the list",
+			Action: hostess.Apply,
+			Flags:  app.Flags,
+		},
 	}
 
 	// switch flag.Arg(0) {

commands.go

@@ -7,34 +7,40 @@ import (
 	"strings"
 )
 
+// MaybeErrorln will print an error message unless -q is passed
 func MaybeErrorln(c *cli.Context, message string) {
 	if !c.Bool("q") {
 		os.Stderr.WriteString(fmt.Sprintf("%s: %s\n", c.Command.Name, message))
 	}
 }
 
+// MaybeError will print an error message unless -q is passed and then exit
 func MaybeError(c *cli.Context, message string) {
 	MaybeErrorln(c, message)
 	os.Exit(1)
 }
 
+// MaybePrintln will print a message unless -s is passed
 func MaybePrintln(c *cli.Context, message string) {
 	if !c.Bool("s") {
 		fmt.Println(message)
 	}
 }
 
+// MaybeLoadHostFile will try to load, parse, and return a Hostfile. If we
+// encounter errors we will terminate, unless -f is passed.
 func MaybeLoadHostFile(c *cli.Context) *Hostfile {
 	hostsfile, errs := LoadHostFile()
 	if len(errs) > 0 && !c.Bool("f") {
 		for _, err := range errs {
 			MaybeErrorln(c, err.Error())
 		}
-		MaybeError(c, "Errors while parsing hostsfile")
+		MaybeError(c, "Errors while parsing hostsfile. Try using fix -f")
 	}
 	return hostsfile
 }
 
+// ShowEnabled turns a boolean into a string (On) or (Off)
 func ShowEnabled(on bool) string {
 	if on {
 		return "(On)"
@@ -43,10 +49,13 @@ func ShowEnabled(on bool) string {
 	}
 }
 
+// ShowHostname turns a Hostname into a string for display
 func ShowHostname(hostname Hostname) string {
 	return fmt.Sprintf("%s -> %s %s", hostname.Domain, hostname.Ip, ShowEnabled(hostname.Enabled))
 }
 
+// StrPadRight adds spaces to the right of a string until it reaches l length.
+// If the input string is already that long, do nothing.
 func StrPadRight(s string, l int) string {
 	return s + strings.Repeat(" ", l-len(s))
 }
@@ -58,7 +67,11 @@ func Add(c *cli.Context) {
 
 	hostsfile := MaybeLoadHostFile(c)
 	hostname := Hostname{c.Args()[0], c.Args()[1], true}
-	err := hostsfile.Add(hostname)
+	var err error
+	if !hostsfile.Contains(hostname) {
+		err = hostsfile.Add(hostname)
+	}
+
 	if err == nil {
 		if c.Bool("n") {
 			fmt.Println(hostsfile.Format())
@@ -71,27 +84,61 @@ func Add(c *cli.Context) {
 	}
 }
 
-func Del(c *cli.Context) error {
-	return nil
+func Del(c *cli.Context) {
+	if len(c.Args()) != 1 {
+		MaybeError(c, "expected <hostname>")
+	}
+	domain := c.Args()[0]
+	hostsfile := MaybeLoadHostFile(c)
+
+	found := hostsfile.ContainsDomain(domain)
+	if found {
+		hostsfile.Delete(domain)
+		if c.Bool("n") {
+			fmt.Println(hostsfile.Format())
+		} else {
+			MaybePrintln(c, fmt.Sprintf("Deleted %s", domain))
+			hostsfile.Save()
+		}
+	} else {
+		MaybePrintln(c, fmt.Sprintf("%s not found in %s", domain, GetHostsPath()))
+	}
 }
 
-func Has(c *cli.Context) error {
-	return nil
+func Has(c *cli.Context) {
+	if len(c.Args()) != 1 {
+		MaybeError(c, "expected <hostname>")
+	}
+	domain := c.Args()[0]
+	hostsfile := MaybeLoadHostFile(c)
+
+	found := hostsfile.ContainsDomain(domain)
+	if found {
+		MaybePrintln(c, fmt.Sprintf("Found %s in %s", domain, GetHostsPath()))
+	} else {
+		MaybeError(c, fmt.Sprintf("%s not found in %s", domain, GetHostsPath()))
+	}
+
 }
 
-func Off(c *cli.Context) error {
-	return nil
+func Off(c *cli.Context) {
+	if len(c.Args()) != 1 {
+		MaybeError(c, "expected <hostname>")
+	}
+
 }
 
-func On(c *cli.Context) error {
-	return nil
+func On(c *cli.Context) {
+	if len(c.Args()) != 1 {
+		MaybeError(c, "expected <hostname>")
+	}
 }
 
 func Ls(c *cli.Context) {
-	hostfile := MaybeLoadHostFile(c)
+	hostsfile := MaybeLoadHostFile(c)
 	maxdomain := 0
 	maxip := 0
-	for _, hostname := range hostfile.Hosts {
+	for _, hostname := range hostsfile.Hosts {
 		dlen := len(hostname.Domain)
 		if dlen > maxdomain {
 			maxdomain = dlen
@@ -102,8 +149,8 @@ func Ls(c *cli.Context) {
 		}
 	}
 
-	for _, domain := range hostfile.ListDomains() {
-		hostname := hostfile.Hosts[domain]
+	for _, domain := range hostsfile.ListDomains() {
+		hostname := hostsfile.Hosts[domain]
 		fmt.Printf("%s -> %s %s\n",
 			StrPadRight(hostname.Domain, maxdomain),
 			StrPadRight(hostname.Ip, maxip),
@@ -121,18 +168,18 @@ whitespace and comments will be removed.
 `
 
 func Fix(c *cli.Context) {
-	hostfile := MaybeLoadHostFile(c)
+	hostsfile := MaybeLoadHostFile(c)
 	if c.Bool("n") {
-		fmt.Println(hostfile.Format())
+		fmt.Println(hostsfile.Format())
 	} else {
-		hostfile.Save()
+		hostsfile.Save()
 	}
 }
 
-func Dump(c *cli.Context) error {
-	return nil
+func Dump(c *cli.Context) {
+
 }
 
-func Apply(c *cli.Context) error {
-	return nil
+func Apply(c *cli.Context) {
+
 }

hostess.go

@@ -137,6 +137,13 @@ func (h *Hostname) Format() string {
 	return r
 }
 
+func (a *Hostname) Equals(b Hostname) bool {
+	if a.Domain == b.Domain && a.Ip == b.Ip {
+		return true
+	}
+	return false
+}
+
 // Hostfile represents /etc/hosts (or a similar file, depending on OS), and
 // includes a list of Hostnames. Hostfile includes
 type Hostfile struct {
@@ -319,6 +326,24 @@ func (h *Hostfile) Save() error {
 	return nil
 }
 
+func (h *Hostfile) Contains(b Hostname) bool {
+	for _, a := range h.Hosts {
+		if a.Equals(b) {
+			return true
+		}
+	}
+	return false
+}
+
+func (h *Hostfile) ContainsDomain(search string) bool {
+	for _, hostname := range h.Hosts {
+		if hostname.Domain == search {
+			return true
+		}
+	}
+	return false
+}
+
 func (h *Hostfile) Add(host Hostname) error {
 	host_f, found := h.Hosts[host.Domain]
 	if found {