Remove 'gorilla' framework

It was being used for session management, but we weren't using any of
the features that differentiated it from using go's cookies directly so
it is hard to justify the additional dependencies.

main.go

@@ -4,7 +4,6 @@ package main
 
 import (
 	"flag"
-	"github.com/gorilla/context"
 	"log"
 	"net"
 	"net/http"
@@ -76,8 +75,8 @@ func main() {
 
 	log.Printf("Serving on port %d out of directory: %s", config.MoneyGo.Port, config.MoneyGo.Basedir)
 	if config.MoneyGo.Fcgi {
-		fcgi.Serve(listener, context.ClearHandler(servemux))
+		fcgi.Serve(listener, servemux)
 	} else {
-		http.Serve(listener, context.ClearHandler(servemux))
+		http.Serve(listener, servemux)
 	}
 }

sessions.go

@@ -1,16 +1,16 @@
 package main
 
 import (
+	"crypto/rand"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
-	"github.com/gorilla/securecookie"
-	"github.com/gorilla/sessions"
+	"io"
 	"log"
 	"net/http"
+	"time"
 )
 
-var cookie_store = sessions.NewCookieStore(securecookie.GenerateRandomKey(64))
-
 type Session struct {
 	SessionId     int64
 	SessionSecret string `json:"-"`
@@ -25,14 +25,13 @@ func (s *Session) Write(w http.ResponseWriter) error {
 func GetSession(r *http.Request) (*Session, error) {
 	var s Session
 
-	session, _ := cookie_store.Get(r, "moneygo")
-	_, ok := session.Values["session-secret"]
-	if !ok {
-		return nil, fmt.Errorf("session-secret cookie not set")
+	cookie, err := r.Cookie("moneygo-session")
+	if err != nil {
+		return nil, fmt.Errorf("moneygo-session cookie not set")
 	}
-	s.SessionSecret = session.Values["session-secret"].(string)
+	s.SessionSecret = cookie.Value
 
-	err := DB.SelectOne(&s, "SELECT * from sessions where SessionSecret=?", s.SessionSecret)
+	err = DB.SelectOne(&s, "SELECT * from sessions where SessionSecret=?", s.SessionSecret)
 	if err != nil {
 		return nil, err
 	}
@@ -46,26 +45,41 @@ func DeleteSessionIfExists(r *http.Request) {
 	}
 }
 
+func NewSessionCookie() (string, error) {
+	bits := make([]byte, 128)
+	if _, err := io.ReadFull(rand.Reader, bits); err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(bits), nil
+}
+
 func NewSession(w http.ResponseWriter, r *http.Request, userid int64) (*Session, error) {
 	s := Session{}
 
-	session, _ := cookie_store.Get(r, "moneygo")
+	session_secret, err := NewSessionCookie()
+	if err != nil {
+		return nil, err
+	}
 
-	session.Values["session-secret"] = string(securecookie.GenerateRandomKey(64))
-	s.SessionSecret = session.Values["session-secret"].(string)
+	cookie := http.Cookie{
+		Name:     "moneygo-session",
+		Value:    session_secret,
+		Path:     "/",
+		Domain:   r.URL.Host,
+		Expires:  time.Now().AddDate(0, 1, 0), // a month from now
+		Secure:   true,
+		HttpOnly: true,
+	}
+	http.SetCookie(w, &cookie)
+
+	s.SessionSecret = session_secret
 	s.UserId = userid
 
-	err := DB.Insert(&s)
+	err = DB.Insert(&s)
 	if err != nil {
 		return nil, err
 	}
-
-	err = session.Save(r, w)
-	if err != nil {
-		return nil, err
-	} else {
 	return &s, nil
-	}
 }
 
 func SessionHandler(w http.ResponseWriter, r *http.Request) {