Improve SQL

cmd/bcrypt/bcrypt.go

@@ -1,41 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"os"
-
-	"golang.org/x/crypto/bcrypt"
-)
-
-func main() {
-	switch os.Args[1] {
-	case "hash":
-		hash(os.Args[2])
-	case "compare":
-		compare(os.Args[2], os.Args[3])
-	default:
-		fmt.Printf("Invalid command: %v\n", os.Args[1])
-	}
-}
-
-func hash(password string) {
-	fmt.Printf("Hash the password %q\n", password)
-	hashedBytes, err := bcrypt.GenerateFromPassword(
-		[]byte(password), bcrypt.DefaultCost)
-	if err != nil {
-		fmt.Printf("error hashing: %v\n", err)
-		return
-	}
-	hash := string(hashedBytes)
-	fmt.Println(hash)
-}
-
-func compare(password, hash string) {
-	fmt.Printf("Compare the password %q with the hash %q\n", password, hash)
-	err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(password))
-	if err != nil {
-		fmt.Printf("Password is invalid: %v\n", password)
-		return
-	}
-	fmt.Println("Password is correct!")
-}

cmd/exp/exp.go

@@ -1,144 +0,0 @@
-package main
-
-import (
-	"database/sql"
-	"fmt"
-	_ "github.com/jackc/pgx/v4/stdlib"
-)
-
-func AddUser(db *sql.DB, name string, email string) (error, int) {
-	row := db.QueryRow(`
-    INSERT INTO users(name, email)
-    VALUES($1, $2)
-    RETURNING id;
-  `, name, email)
-	var id int
-	err := row.Scan(&id)
-	return err, id
-}
-
-func QueryUser(db *sql.DB, id int) (error, string, string) {
-	row := db.QueryRow(`
-  SELECT name, email
-  FROM users
-  WHERE id=$1;`, id)
-	var name, email string
-	err := row.Scan(&name, &email)
-	return err, name, email
-}
-
-type Order struct {
-	ID     int
-	UID    int
-	Amount int
-	Desc   string
-}
-
-func AddOrder(db *sql.DB, uid int, amount int, desc string) (error, int) {
-	row := db.QueryRow(`
-    insert into orders(user_id, amount, description)
-    values($1, $2, $3)
-    returning id;
-  `, uid, amount, desc)
-	var id int
-	err := row.Scan(&id)
-	return err, id
-}
-
-func QueryOrders(db *sql.DB, uid int) ([]Order, error) {
-	var orders []Order
-	rows, err := db.Query(`
-    select id, amount, description from orders where user_id=$1
-  `, uid)
-	if err != nil {
-		return orders, err
-	}
-	defer rows.Close()
-	for rows.Next() {
-		var order Order
-		order.UID = uid
-		err := rows.Scan(&order.ID, &order.Amount, &order.Desc)
-		if err != nil {
-			return orders, err
-		}
-		orders = append(orders, order)
-	}
-	err = rows.Err()
-	return orders, err
-}
-
-func main() {
-	db, err := sql.Open("pgx", "host=localhost port=5432 user=baloo  dbname=lenslocked sslmode=disable")
-	if err != nil {
-		panic(err)
-	}
-	defer db.Close()
-	err = db.Ping()
-	if err != nil {
-		panic(err)
-	}
-
-	fmt.Println("Connected!")
-	_, err = db.Exec(`
-  create table if not exists users (
-    id serial primary key,
-    name text,
-    email text not null
-  );
-  create table if not exists orders (
-    id serial primary key,
-    user_id int not null,
-    amount int,
-    description text
-  );`)
-	if err != nil {
-		panic(err)
-	}
-	fmt.Println("Tables created")
-
-	var name string
-	var email string
-
-	// Create User
-	/*
-		name = "Jon Rob Baker"
-		email = "demo@user.com"
-		err, id := AddUser(db, name, email)
-		if err != nil {
-			panic(err)
-		}
-		fmt.Println("User ", id, " created")
-	*/
-
-	// Query User
-	err, name, email = QueryUser(db, 5)
-	if err == sql.ErrNoRows {
-		fmt.Println("Error, no rows!")
-	}
-	if err != nil {
-		panic(err)
-	}
-	fmt.Printf("User information: name=%s, email=%s\n", name, email)
-
-	uid := 5
-
-	// Create fake orders
-	/*
-		for i := 1; i <= 5; i++ {
-			amount := i * 100
-			desc := fmt.Sprintf("Fake order #%d", i)
-			err, _ := AddOrder(db, uid, amount, desc)
-			if err != nil {
-				panic(err)
-			}
-		}
-		fmt.Println("Created fake orders")
-	*/
-
-	// Query Orders
-	orders, err := QueryOrders(db, uid)
-	if err != nil {
-		panic(err)
-	}
-	fmt.Println("Orders: ", orders)
-}

cmd/tplfn/tplfn.go

@@ -1,26 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"html/template"
-	"os"
-)
-
-func main() {
-	tplstr := "hello {{myFunc}}\n"
-
-	fmap := template.FuncMap{}
-	fmap["myFunc"] = func() (string, error) {
-		return "world", fmt.Errorf("hi")
-	}
-
-	tpl, err := template.New("demo").Funcs(fmap).Parse(tplstr)
-	if err != nil {
-		panic(fmt.Errorf("Error creating template: %v", err))
-	}
-
-	err = tpl.Execute(os.Stdout, nil)
-	if err != nil {
-		panic(err)
-	}
-}

controllers/users.go

@@ -15,6 +15,7 @@ type Users struct {
 		Signin Template
 	}
 	UserService    *models.UserService
+	SessionService *models.SessionService
 }
 
 func (u Users) GetSignup(w http.ResponseWriter, r *http.Request) {
@@ -34,7 +35,22 @@ func (u Users) PostSignup(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
 		return
 	}
-	fmt.Fprintf(w, "User created: %+v", user)
+	session, err := u.SessionService.Create(user.ID)
+	if err != nil {
+		fmt.Println(err)
+		http.Redirect(w, r, "/signin", http.StatusFound)
+		return
+	}
+
+	cookie := http.Cookie{
+		Name:     "session",
+		Value:    session.Token,
+		Path:     "/",
+		HttpOnly: true,
+	}
+	http.SetCookie(w, &cookie)
+
+	http.Redirect(w, r, "/user", http.StatusFound)
 }
 
 func (u Users) GetSignin(w http.ResponseWriter, r *http.Request) {
@@ -58,36 +74,70 @@ func (u Users) PostSignin(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// Bad cookie
+	session, err := u.SessionService.Create(user.ID)
+	if err != nil {
+		fmt.Println(err)
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
 	cookie := http.Cookie{
-		Name:     "bad",
+		Name:     "session",
-		Value:    user.Email,
+		Value:    session.Token,
 		Path:     "/",
 		HttpOnly: true,
 	}
 	http.SetCookie(w, &cookie)
 
-	fmt.Fprintf(w, "User authenticated: %+v", user)
+	http.Redirect(w, r, "/user", http.StatusFound)
+}
+
+func (u Users) GetSignout(w http.ResponseWriter, r *http.Request) {
+	sessionCookie, err := r.Cookie("session")
+	if err != nil {
+		http.Redirect(w, r, "/signin", http.StatusFound)
+		return
+	}
+	err = u.SessionService.Delete(sessionCookie.Value)
+	if err != nil {
+		fmt.Println(err)
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+	c := http.Cookie{
+		Name:   "session",
+		MaxAge: -1,
+	}
+	http.SetCookie(w, &c)
+	http.Redirect(w, r, "/signin", http.StatusFound)
 }
 
 func (u Users) CurrentUser(w http.ResponseWriter, r *http.Request) {
-	email, err := r.Cookie("bad")
+	seshCookie, err := r.Cookie("session")
 	if err != nil {
-		fmt.Fprint(w, "The bad cookie could not be read.")
+		fmt.Println(err)
+		http.Redirect(w, r, "/signin", http.StatusFound)
 		return
 	}
-	fmt.Fprintf(w, "Bad cookie: %s\n", email.Value)
+	user, err := u.SessionService.User(seshCookie.Value)
+	if err != nil {
+		fmt.Println(err)
+		http.Redirect(w, r, "/signin", http.StatusFound)
+		return
+	}
+	fmt.Fprintf(w, "Current user: %s\n", user.Email)
 }
 
-func WithTemplates(user_service *models.UserService, signup Template, signin Template) Users {
+func WithTemplates(user_service *models.UserService, session_service *models.SessionService, signup Template, signin Template) Users {
 	u := Users{}
 	u.Templates.Signup = signup
 	u.Templates.Signin = signin
 	u.UserService = user_service
+	u.SessionService = session_service
 	return u
 }
 
-func Default(user_service *models.UserService, templatePath ...string) Users {
+func Default(user_service *models.UserService, session_service *models.SessionService) Users {
 	signup_tpl := views.Must(views.FromFS(templates.FS, "signup.gohtml", "tailwind.gohtml"))
 	signin_tpl := views.Must(views.FromFS(templates.FS, "signin.gohtml", "tailwind.gohtml"))
 
@@ -100,5 +150,5 @@ func Default(user_service *models.UserService, templatePath ...string) Users {
 		panic(err)
 	}
 
-	return WithTemplates(user_service, signup_tpl, signin_tpl)
+	return WithTemplates(user_service, session_service, signup_tpl, signin_tpl)
 }

go.mod

@@ -6,10 +6,11 @@ require (
 	github.com/go-chi/chi/v5 v5.1.0
 	github.com/jackc/pgx/v4 v4.18.3
 	golang.org/x/crypto v0.26.0
+	google.golang.org/grpc v1.65.0
 )
 
 require (
-	github.com/gorilla/csrf v1.7.2
+	github.com/gorilla/csrf v1.7.2 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
 	github.com/jackc/chunkreader/v2 v2.0.1 // indirect
 	github.com/jackc/pgconn v1.14.3 // indirect
@@ -18,5 +19,7 @@ require (
 	github.com/jackc/pgproto3/v2 v2.3.3 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
 	github.com/jackc/pgtype v1.14.0 // indirect
+	golang.org/x/sys v0.23.0 // indirect
 	golang.org/x/text v0.17.0 // indirect
+	google.golang.org/protobuf v1.34.1 // indirect
 )

go.sum

@@ -16,8 +16,8 @@ github.com/go-logfmt/logfmt v0.5.0/go.mod h1:wCYkCAKZfumFQihp8CzCvQ3paCTfi41vtzG
 github.com/go-stack/stack v1.8.0/go.mod h1:v0f6uXyyMGvRgIKkXu+yp6POWl0qKG85gN/melR3HDY=
 github.com/gofrs/uuid v4.0.0+incompatible h1:1SD/1F5pU8p29ybwgQSwpQk+mwdRrXCYuPhW6m+TnJw=
 github.com/gofrs/uuid v4.0.0+incompatible/go.mod h1:b2aQJv3Z4Fp6yNu3cdSllBxTCLRxnplIgP/c0N/04lM=
-github.com/google/gofuzz v1.2.0 h1:xRy4A+RhZaiKjJ1bPfwQ8sedCA+YS2YcCHW6ec7JMi0=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
-github.com/google/gofuzz v1.2.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
 github.com/gorilla/csrf v1.7.2 h1:oTUjx0vyf2T+wkrx09Trsev1TE+/EbDAeHtSTbtC2eI=
 github.com/gorilla/csrf v1.7.2/go.mod h1:F1Fj3KG23WYHE6gozCmBAezKookxbIvUJT+121wTuLk=
@@ -142,6 +142,8 @@ golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190813141303-74dc4d7220e7/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.25.0 h1:d/OCCoBEUq33pjydKrGQhw7IlUPI2Oylr+8qLx49kac=
+golang.org/x/net v0.25.0/go.mod h1:JkAGAh7GEvH74S6FOH42FLoXpXbE/aqXSrIQjXgsiwM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -155,6 +157,8 @@ golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.23.0 h1:YfKFowiIMvtgl1UERQoTPPToxltDeZfbj4H7dVUCwmM=
+golang.org/x/sys v0.23.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -177,6 +181,12 @@ golang.org/x/xerrors v0.0.0-20190513163551-3ee3066db522/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240528184218-531527333157 h1:Zy9XzmMEflZ/MAaA7vNcoebnRAld7FsPW1EeBB7V0m8=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240528184218-531527333157/go.mod h1:EfXuqaE1J41VCDicxHzUDm+8rk+7ZdXzHV0IhO/I6s0=
+google.golang.org/grpc v1.65.0 h1:bs/cUb4lp1G5iImFFd3u5ixQzweKizoZJAwBNLR42lc=
+google.golang.org/grpc v1.65.0/go.mod h1:WgYC2ypjlB0EiQi6wdKixMqukr6lBc0Vo+oOgjrM5ZQ=
+google.golang.org/protobuf v1.34.1 h1:9ddQBjfCyZPOHPUiPxpYESBLc+T8P3E+Vo4IbKZgFWg=
+google.golang.org/protobuf v1.34.1/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=

main.go

@@ -38,14 +38,15 @@ func ConnectDB() *sql.DB {
 func main() {
 	csrfKey := []byte(os.Getenv("LENSLOCKED_CSRF_KEY"))
 	if len(csrfKey) < 32 {
-		panic("Error: bad csrf protection key")
+		panic("Error: bad csrf protection key\nPlease set a key with the LENSLOCKED_CSRF_KEY env var.")
 	}
 
 	db := ConnectDB()
 	defer db.Close()
 
 	userService := models.UserService{DB: db}
-	var usersCtrlr ctrlrs.Users = ctrlrs.Default(&userService)
+	sessionService := models.SessionService{DB: db}
+	var usersCtrlr ctrlrs.Users = ctrlrs.Default(&userService, &sessionService)
 
 	r := chi.NewRouter()
 
@@ -59,6 +60,7 @@ func main() {
 	r.Post("/signup", usersCtrlr.PostSignup)
 	r.Get("/signin", usersCtrlr.GetSignin)
 	r.Post("/signin", usersCtrlr.PostSignin)
+	r.Post("/signout", usersCtrlr.GetSignout)
 
 	r.Get("/user", usersCtrlr.CurrentUser)
 

models/sessions.go

@@ -0,0 +1,105 @@
+package models
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"database/sql"
+	"encoding/base64"
+	"fmt"
+)
+
+func RandBytes(n int) ([]byte, error) {
+	b := make([]byte, n)
+	nRead, err := rand.Read(b)
+	if err != nil {
+		return nil, fmt.Errorf("bytes: %w", err)
+	}
+	if nRead < n {
+		return nil, fmt.Errorf("bytes: didn't read enough random bytes")
+	}
+	return b, nil
+}
+func RandString(n int) (string, error) {
+	b, err := RandBytes(n)
+	if err != nil {
+		return "", fmt.Errorf("string: %w", err)
+	}
+	return base64.URLEncoding.EncodeToString(b), nil
+}
+
+const SessionTokenBytes = 32
+
+func SessionToken() (string, error) {
+	return RandString(SessionTokenBytes)
+}
+func hash(token string) string {
+	tokenHash := sha256.Sum256([]byte(token))
+	return base64.StdEncoding.EncodeToString(tokenHash[:])
+}
+
+type Session struct {
+	ID        int
+	UserID    int
+	TokenHash string
+	// Token is only set when creating a new session. When looking up a session
+	// this will be left empty, as we only store the hash of a session token
+	// in our database and we cannot reverse it into a raw token.
+	Token string
+}
+
+type SessionService struct {
+	DB *sql.DB
+}
+
+func (ss *SessionService) Create(userID int) (*Session, error) {
+	token, err := SessionToken()
+	if err != nil {
+		return nil, fmt.Errorf("create: %w", err)
+	}
+	session := Session{
+		UserID:    userID,
+		Token:     token,
+		TokenHash: hash(token),
+	}
+	row := ss.DB.QueryRow(`
+    INSERT INTO sessions (user_id, token_hash)
+		VALUES ($1, $2) ON CONFLICT (user_id) DO
+		UPDATE
+		SET token_hash = $2
+		RETURNING id;
+  `, session.UserID, session.TokenHash)
+	err = row.Scan(&session.ID)
+	if err != nil {
+		return nil, fmt.Errorf("create: %w", err)
+	}
+	return &session, nil
+}
+
+func (ss *SessionService) Delete(token string) error {
+	tokenHash := hash(token)
+	_, err := ss.DB.Exec(`DELETE FROM sessions WHERE token_hash = $1;`, tokenHash)
+	if err != nil {
+		return fmt.Errorf("delete: %w", err)
+	}
+	return nil
+}
+
+func (ss *SessionService) User(token string) (*User, error) {
+	token_hash := hash(token)
+	var user User
+
+	row := ss.DB.QueryRow(`
+    SELECT users.id,
+      users.email,
+      users.password_hash
+    FROM sessions
+      JOIN users ON users.id = sessions.user_id
+    WHERE sessions.token_hash = $1;
+  `, token_hash)
+	err := row.Scan(&user.ID, &user.Email, &user.PasswordHash)
+	if err != nil {
+		return nil, fmt.Errorf("user: %w", err)
+	}
+
+	return &user, err
+}

models/sql/sessions.sql

@@ -0,0 +1,5 @@
+CREATE TABLE sessions (
+  id SERIAL PRIMARY KEY,
+  user_id INT UNIQUE REFERENCES users (id) ON DELETE CASCADE,
+  token_hash TEXT UNIQUE NOT NULL
+);

templates/tailwind.gohtml

@@ -16,6 +16,10 @@
           <a class="text-base font-semibold hover:text-blue-100 pr-8" href="/faq">FAQ</a>
         </div>
         <div class="space-x-4">
+          <form action="/signout" method="post" class="inline pr-4">
+            {{csrfField}}
+            <button type="submit">Sign out</button>
+          </form>
           <a href="/signin">Sign in</a>
           <a href="/signup" clss="px-4 py-2 bg-blue-700 hover:bg-blue-600 rounded">Sign up</a>
         </div>

views/template.go

@@ -1,8 +1,10 @@
 package views
 
 import (
+	"bytes"
 	"fmt"
 	"html/template"
+	"io"
 	"io/fs"
 	"log"
 	"net/http"
@@ -29,12 +31,14 @@ func (t Template) Execute(w http.ResponseWriter, r *http.Request, data interface
 	})
 
 	w.Header().Set("Content-Type", "text/html; charset=utf8")
-	err = tpl.Execute(w, data)
+	var buf bytes.Buffer
+	err = tpl.Execute(&buf, data)
 	if err != nil {
 		log.Printf("Error executing template: %v", err)
 		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
 		return
 	}
+	io.Copy(w, &buf)
 }
 func (t Template) TestTemplate(data interface{}) error {
 	var testWriter strings.Builder
@@ -42,6 +46,11 @@ func (t Template) TestTemplate(data interface{}) error {
 	if err != nil {
 		return err
 	}
+	tpl = tpl.Funcs(template.FuncMap{
+		"csrfField": func() template.HTML {
+			return `<div class="hidden">STUB: PLACEHOLDER</div>`
+		},
+	})
 	return tpl.Execute(&testWriter, data)
 }
 
@@ -52,8 +61,8 @@ func FromFile(pattern ...string) (Template, error) {
 func FromFS(fs fs.FS, pattern ...string) (Template, error) {
 	tpl := template.New(pattern[0])
 	tpl = tpl.Funcs(template.FuncMap{
-		"csrfField": func() template.HTML {
+		"csrfField": func() (template.HTML, error) {
-			return `<div class="hidden">STUB: PLACEHOLDER</div>`
+			return `<div class="hidden">STUB: PLACEHOLDER</div>`, fmt.Errorf("csrfField Not Implimented")
 		},
 	})
 	tpl, err := tpl.ParseFS(fs, pattern...)