implement partitioned cookies

implement cookie validation with error logging
refactor c.SetCookie to accept option pattern modifications as vararg
refactor c.SetSameSite to use option pattern under the hood

context.go

@@ -6,9 +6,11 @@ package gin
 
 import (
 	"errors"
+	"fmt"
 	"io"
 	"io/fs"
 	"log"
+	"log/slog"
 	"math"
 	"mime/multipart"
 	"net"
@@ -47,6 +49,20 @@ const ContextKey = "_gin-gonic/gin/contextkey"
 
 type ContextKeyType int
 
+type CookieOption func(*http.Cookie)
+
+func WithPartitionedCookie(partitioned bool) CookieOption {
+	return func(cookie *http.Cookie) {
+		cookie.Partitioned = partitioned
+	}
+}
+
+func WithSameSiteCookie(sameSite http.SameSite) CookieOption {
+	return func(cookie *http.Cookie) {
+		cookie.SameSite = sameSite
+	}
+}
+
 const ContextRequestKey ContextKeyType = 0
 
 // abortIndex represents a typical value used in abort functions.
@@ -87,9 +103,9 @@ type Context struct {
 	// or PUT body parameters.
 	formCache url.Values
 
-	// SameSite allows a server to define a cookie attribute making it impossible for
-	// the browser to send this cookie along with cross-site requests.
-	sameSite http.SameSite
+	// cookieOptions set up additional cookie parameters to be used with http.Cookie
+	// this is needed to prevent breaking existing implementations
+	cookieOptions []CookieOption
 }
 
 /************************************/
@@ -108,7 +124,7 @@ func (c *Context) reset() {
 	c.Accepted = nil
 	c.queryCache = nil
 	c.formCache = nil
-	c.sameSite = 0
+	c.cookieOptions = make([]CookieOption, 0)
 	*c.params = (*c.params)[:0]
 	*c.skippedNodes = (*c.skippedNodes)[:0]
 }
@@ -1005,26 +1021,38 @@ func (c *Context) GetRawData() ([]byte, error) {
 
 // SetSameSite with cookie
 func (c *Context) SetSameSite(samesite http.SameSite) {
-	c.sameSite = samesite
+	c.cookieOptions = append(c.cookieOptions, WithSameSiteCookie(samesite))
 }
 
 // SetCookie adds a Set-Cookie header to the ResponseWriter's headers.
 // The provided cookie must have a valid Name. Invalid cookies may be
 // silently dropped.
-func (c *Context) SetCookie(name, value string, maxAge int, path, domain string, secure, httpOnly bool) {
+func (c *Context) SetCookie(name, value string, maxAge int, path, domain string, secure, httpOnly bool, options ...CookieOption) {
 	if path == "" {
 		path = "/"
 	}
-	http.SetCookie(c.Writer, &http.Cookie{
+
+	cookie := &http.Cookie{
 		Name:     name,
 		Value:    url.QueryEscape(value),
 		MaxAge:   maxAge,
 		Path:     path,
 		Domain:   domain,
-		SameSite: c.sameSite,
 		Secure:   secure,
 		HttpOnly: httpOnly,
-	})
+	}
+
+	for _, option := range c.cookieOptions {
+		option(cookie)
+	}
+	for _, option := range options {
+		option(cookie)
+	}
+	if err := cookie.Valid(); err != nil {
+		slog.Error(fmt.Sprintf("invalid cookie: %v", err))
+	}
+
+	http.SetCookie(c.Writer, cookie)
 }
 
 // Cookie returns the named cookie provided in the request or

context_test.go

@@ -206,6 +206,7 @@ func TestContextReset(t *testing.T) {
 	c.Params = Params{Param{}}
 	c.Error(errors.New("test")) //nolint: errcheck
 	c.Set("foo", "bar")
+	c.SetSameSite(http.SameSiteLaxMode)
 	c.reset()
 
 	assert.False(t, c.IsAborted())
@@ -215,6 +216,7 @@ func TestContextReset(t *testing.T) {
 	assert.Empty(t, c.Errors.Errors())
 	assert.Empty(t, c.Errors.ByType(ErrorTypeAny))
 	assert.Empty(t, c.Params)
+	assert.Empty(t, c.cookieOptions)
 	assert.EqualValues(t, c.index, -1)
 	assert.Equal(t, c.Writer.(*responseWriter), &c.writermem)
 }
@@ -866,6 +868,18 @@ func TestContextSetCookie(t *testing.T) {
 	assert.Equal(t, "user=gin; Path=/; Domain=localhost; Max-Age=1; HttpOnly; Secure; SameSite=Lax", c.Writer.Header().Get("Set-Cookie"))
 }
 
+func TestContextSetCookieWithOptions(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.SetCookie("user", "gin", 1, "/", "localhost", true, true, WithSameSiteCookie(http.SameSiteLaxMode), WithPartitionedCookie(true))
+	assert.Equal(t, "user=gin; Path=/; Domain=localhost; Max-Age=1; HttpOnly; Secure; SameSite=Lax; Partitioned", c.Writer.Header().Get("Set-Cookie"))
+}
+
+func TestContextSetCookieWithNonSecurePartition(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.SetCookie("user", "gin", 1, "/", "localhost", false, true, WithPartitionedCookie(true))
+	assert.Equal(t, "user=gin; Path=/; Domain=localhost; Max-Age=1; HttpOnly; Partitioned", c.Writer.Header().Get("Set-Cookie"))
+}
+
 func TestContextSetCookiePathEmpty(t *testing.T) {
 	c, _ := CreateTestContext(httptest.NewRecorder())
 	c.SetSameSite(http.SameSiteLaxMode)