ch15.2

internal/data/models.go

@@ -13,6 +13,7 @@ var (
 type Models struct {
 	Movies MovieModel
 	Users  UserModel
+	Tokens TokenModel
 }
 
 // type Models struct {
@@ -29,6 +30,7 @@ func NewModels(db *sql.DB) Models {
 	return Models{
 		Movies: MovieModel{DB: db},
 		Users:  UserModel{DB: db},
+		Tokens: TokenModel{DB: db},
 	}
 }
 

internal/data/tokens.go

@@ -0,0 +1,91 @@
+package data
+
+import (
+	"context"
+	"crypto/rand"
+	"crypto/sha256"
+	"database/sql"
+	"encoding/base32"
+	"time"
+
+	"gitea.local.lab/Lbenedar/greenlight/internal/validator"
+)
+
+const (
+	ScopeActivation = "activation"
+)
+
+type Token struct {
+	Plaintext string
+	Hash      []byte
+	UserID    int64
+	Expiry    time.Time
+	Scope     string
+}
+
+func generateToken(userID int64, ttl time.Duration, scope string) (*Token, error) {
+	token := &Token{
+		UserID: userID,
+		Expiry: time.Now().Add(ttl),
+		Scope:  scope,
+	}
+
+	randomBytes := make([]byte, 16)
+
+	_, err := rand.Read(randomBytes)
+	if err != nil {
+		return nil, err
+	}
+
+	token.Plaintext = base32.StdEncoding.WithPadding(base32.NoPadding).EncodeToString(randomBytes)
+
+	hash := sha256.Sum256([]byte(token.Plaintext))
+	token.Hash = hash[:]
+
+	return token, nil
+}
+
+func ValidateTokenPlaintext(v *validator.Validator, tokenPlaintext string) {
+	v.Check(tokenPlaintext != "", "token", "must be provided")
+	v.Check(len(tokenPlaintext) == 26, "token", "must be 26 bytes long")
+}
+
+type TokenModel struct {
+	DB *sql.DB
+}
+
+func (m TokenModel) New(userID int64, ttl time.Duration, scope string) (*Token, error) {
+	token, err := generateToken(userID, ttl, scope)
+	if err != nil {
+		return nil, err
+	}
+
+	err = m.Insert(token)
+	return token, err
+}
+
+func (m TokenModel) Insert(token *Token) error {
+	query := `
+		INSERT INTO tokens (hash, user_id, expirt, scope)
+		VALUES ($1, $2, $3, $4)`
+
+	args := []any{token.Hash, token.UserID, token.Expiry, token.Scope}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	defer cancel()
+
+	_, err := m.DB.ExecContext(ctx, query, args...)
+	return err
+}
+
+func (m TokenModel) DeleteForUser(scope string, userID int64) error {
+	query := `
+		DELETE FROM tokens
+		WHERE scope = $1 AND user_id = $2`
+
+	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	defer cancel()
+
+	_, err := m.DB.ExecContext(ctx, query, scope, userID)
+	return err
+}

migrations/000005_create_tokens_table.down.sql

@@ -0,0 +1 @@
+DROP TABLE IF EXISTS tokens;

migrations/000005_create_tokens_table.up.sql

@@ -0,0 +1,6 @@
+CREATE TABLE IF NOT EXISTS tokens {
+    hash bytea PRIMARY KEY,
+    user_id bigint NOT NULL REFERENCES users ON DELETE CASCADE,
+    expiry timestamp(0) with time zone NOT NULL,
+    scope text NOT NULL
+};