feat: token creation, email templace change, activate user endpoint

projects/greenlight/internal/data/users.go

@@ -2,6 +2,7 @@ package data
 
 import (
 	"context"
+	"crypto/sha256"
 	"database/sql"
 	"errors"
 	"time"
@@ -213,3 +214,52 @@ func (m UserModel) Update(user *User) error {
 
 	return nil
 }
+
+func (m UserModel) GetForToken(tokenScope, tokenPlaintext string) (*User, error) {
+	// Calculate the SHA-256 hash of the plaintext token provided by the client.
+	// Remember that this returns a byte *array* with length 32, not a slice.
+	tokenHash := sha256.Sum256([]byte(tokenPlaintext))
+	// Set up the SQL query.
+	query := `
+        SELECT users.id, users.created_at, users.name, users.email, users.password_hash, users.activated, users.version
+        FROM users
+        INNER JOIN tokens
+        ON users.id = tokens.user_id
+        WHERE tokens.hash = $1
+        AND tokens.scope = $2 
+        AND tokens.expiry > $3`
+
+	// Create a slice containing the query arguments. Notice how we use the [:] operator
+	// to get a slice containing the token hash, rather than passing in the array (which
+	// is not supported by the pq driver), and that we pass the current time as the
+	// value to check against the token expiry.
+	args := []interface{}{tokenHash[:], tokenScope, time.Now()}
+
+	var user User
+
+	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	defer cancel()
+
+	// Execute the query, scanning the return values into a User struct. If no matching
+	// record is found we return an ErrRecordNotFound error.
+	err := m.DB.QueryRowContext(ctx, query, args...).Scan(
+		&user.ID,
+		&user.CreatedAt,
+		&user.Name,
+		&user.Email,
+		&user.Password.hash,
+		&user.Activated,
+		&user.Version,
+	)
+	if err != nil {
+		switch {
+		case errors.Is(err, sql.ErrNoRows):
+			return nil, ErrRecordNotFound
+		default:
+			return nil, err
+		}
+	}
+
+	// Return the matching user.
+	return &user, nil
+}