Merge a7b757e33830094fcb2af6156cb963a96e87a47b into d7776de7d444935ea4385999711bd6331a98fecb

binding/binding.go

@@ -23,6 +23,7 @@ const (
 	MIMEYAML              = "application/x-yaml"
 	MIMEYAML2             = "application/yaml"
 	MIMETOML              = "application/toml"
+	MIMEBSON              = "application/bson"
 )
 
 // Binding describes the interface which needs to be implemented for binding the
@@ -86,6 +87,7 @@ var (
 	Header        Binding     = headerBinding{}
 	Plain         BindingBody = plainBinding{}
 	TOML          BindingBody = tomlBinding{}
+	BSON          BindingBody = bsonBinding{}
 )
 
 // Default returns the appropriate Binding instance based on the HTTP method
@@ -110,6 +112,8 @@ func Default(method, contentType string) Binding {
 		return TOML
 	case MIMEMultipartPOSTForm:
 		return FormMultipart
+	case MIMEBSON:
+		return BSON
 	default: // case MIMEPOSTForm:
 		return Form
 	}

binding/binding_nomsgpack.go

@@ -21,6 +21,7 @@ const (
 	MIMEYAML              = "application/x-yaml"
 	MIMEYAML2             = "application/yaml"
 	MIMETOML              = "application/toml"
+	MIMEBSON              = "application/bson"
 )
 
 // Binding describes the interface which needs to be implemented for binding the
@@ -82,6 +83,7 @@ var (
 	Header        = headerBinding{}
 	TOML          = tomlBinding{}
 	Plain         = plainBinding{}
+	BSON          BindingBody = bsonBinding{}
 )
 
 // Default returns the appropriate Binding instance based on the HTTP method
@@ -104,6 +106,8 @@ func Default(method, contentType string) Binding {
 		return FormMultipart
 	case MIMETOML:
 		return TOML
+	case MIMEBSON:
+		return BSON
 	default: // case MIMEPOSTForm:
 		return Form
 	}

binding/binding_test.go

@@ -21,6 +21,7 @@ import (
 	"github.com/gin-gonic/gin/testdata/protoexample"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.mongodb.org/mongo-driver/bson"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -172,6 +173,9 @@ func TestBindingDefault(t *testing.T) {
 
 	assert.Equal(t, TOML, Default(http.MethodPost, MIMETOML))
 	assert.Equal(t, TOML, Default(http.MethodPut, MIMETOML))
+
+	assert.Equal(t, BSON, Default(http.MethodPost, MIMEBSON))
+	assert.Equal(t, BSON, Default(http.MethodPut, MIMEBSON))
 }
 
 func TestBindingJSONNilBody(t *testing.T) {
@@ -731,6 +735,18 @@ func TestBindingProtoBufFail(t *testing.T) {
 		string(data), string(data[1:]))
 }
 
+func TestBindingBSON(t *testing.T) {
+	var obj FooStruct
+	obj.Foo = "bar"
+	data, _ := bson.Marshal(&obj)
+	testBodyBinding(t,
+		BSON, "bson",
+		"/", "/",
+		string(data),
+		// note: for badbody, we remove first byte to make it invalid
+		string(data[1:]))
+}
+
 func TestValidationFails(t *testing.T) {
 	var obj FooStruct
 	req := requestWithBody(http.MethodPost, "/", `{"bar": "foo"}`)

binding/bson.go

@@ -0,0 +1,30 @@
+// Copyright 2025 Gin Core Team. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package binding
+
+import (
+	"io"
+	"net/http"
+
+	"go.mongodb.org/mongo-driver/bson"
+)
+
+type bsonBinding struct{}
+
+func (bsonBinding) Name() string {
+	return "bson"
+}
+
+func (b bsonBinding) Bind(req *http.Request, obj any) error {
+	buf, err := io.ReadAll(req.Body)
+	if err == nil {
+		err = b.BindBody(buf, obj)
+	}
+	return err
+}
+
+func (bsonBinding) BindBody(body []byte, obj any) error {
+	return bson.Unmarshal(body, obj)
+}

context.go

@@ -5,6 +5,7 @@
 package gin
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -40,6 +41,7 @@ const (
 	MIMEYAML2             = binding.MIMEYAML2
 	MIMETOML              = binding.MIMETOML
 	MIMEPROTOBUF          = binding.MIMEPROTOBUF
+	MIMEBSON              = binding.MIMEBSON
 )
 
 // BodyBytesKey indicates a default body bytes key.
@@ -93,6 +95,10 @@ type Context struct {
 	// 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
+
+	internalContextMu          sync.RWMutex
+	internalContext            context.Context
+	internalContextCancelCause context.CancelCauseFunc
 }
 
 /************************************/
@@ -114,6 +120,10 @@ func (c *Context) reset() {
 	c.sameSite = 0
 	*c.params = (*c.params)[:0]
 	*c.skippedNodes = (*c.skippedNodes)[:0]
+
+	if c.useInternalContext() {
+		c.WithInternalContext(context.Background())
+	}
 }
 
 // Copy returns a copy of the current context that can be safely used outside the request's scope.
@@ -1237,6 +1247,11 @@ func (c *Context) ProtoBuf(code int, obj any) {
 	c.Render(code, render.ProtoBuf{Data: obj})
 }
 
+// BSON serializes the given struct as BSON into the response body.
+func (c *Context) BSON(code int, obj any) {
+	c.Render(code, render.BSON{Data: obj})
+}
+
 // String writes the given string into the response body.
 func (c *Context) String(code int, format string, values ...any) {
 	c.Render(code, render.String{Format: format, Data: values})
@@ -1344,6 +1359,7 @@ type Negotiate struct {
 	Data         any
 	TOMLData     any
 	PROTOBUFData any
+	BSONData     any
 }
 
 // Negotiate calls different Render according to acceptable Accept format.
@@ -1373,6 +1389,10 @@ func (c *Context) Negotiate(code int, config Negotiate) {
 		data := chooseData(config.PROTOBUFData, config.Data)
 		c.ProtoBuf(code, data)
 
+	case binding.MIMEBSON:
+		data := chooseData(config.BSONData, config.Data)
+		c.BSON(code, data)
+
 	default:
 		c.AbortWithError(http.StatusNotAcceptable, errors.New("the accepted formats are not offered by the server")) //nolint: errcheck
 	}
@@ -1418,6 +1438,49 @@ func (c *Context) SetAccepted(formats ...string) {
 /***** GOLANG.ORG/X/NET/CONTEXT *****/
 /************************************/
 
+// WithInternalContext replaces the internal context stored with the provided one in a thread safe manner.
+// It's important that any context you pass in is not something the wraps *gin.Context,
+// if you want to wrap a context and then provide it to WithInternalContext, use InternalContext().
+// If you don't plan to provide the context back to WithInternalContext you can safely use *Context directly.
+// Otherwise you'll end up with a stack overflow.
+//
+// For example:
+// var c *Context // given a context
+// // you can safely wrap it and pass it downstream
+// myDownstreamFunction(context.WithValue(c, ...))
+//
+// // but when you want to call WithInternalContext you should do it like this
+// c.WithInternalContext(context.WithValue(c.InternalContext(), ...))
+func (c *Context) WithInternalContext(ctx context.Context) {
+	if !c.useInternalContext() {
+		panic("Can't use WithInternalContext when UseInternalContext is false")
+	}
+
+	c.internalContextMu.Lock()
+	defer c.internalContextMu.Unlock()
+
+	c.internalContext, c.internalContextCancelCause = context.WithCancelCause(ctx)
+}
+
+// InternalContext provides the currently stored internal context in a thread safe manner.
+// Use this if you want to wrap a context.Context which you'll end up providing to WithInternalContext.
+// If you don't plan to provide the context back to WithInternalContext you can safely use *Context directly.
+func (c *Context) InternalContext() context.Context {
+	if !c.useInternalContext() {
+		panic("Can't use InternalContext when UseInternalContext is false")
+	}
+
+	c.internalContextMu.RLock()
+	defer c.internalContextMu.RUnlock()
+
+	return c.internalContext
+}
+
+// hasRequestContext returns whether c.Request has Context and fallback.
+func (c *Context) useInternalContext() bool {
+	return c.engine != nil && c.engine.UseInternalContext
+}
+
 // hasRequestContext returns whether c.Request has Context and fallback.
 func (c *Context) hasRequestContext() bool {
 	hasFallback := c.engine != nil && c.engine.ContextWithFallback
@@ -1427,26 +1490,44 @@ func (c *Context) hasRequestContext() bool {
 
 // Deadline returns that there is no deadline (ok==false) when c.Request has no Context.
 func (c *Context) Deadline() (deadline time.Time, ok bool) {
-	if !c.hasRequestContext() {
-		return
+	if c.useInternalContext() {
+		c.internalContextMu.RLock()
+		defer c.internalContextMu.RUnlock()
+
+		return c.internalContext.Deadline()
+	} else if c.hasRequestContext() {
+		return c.Request.Context().Deadline()
 	}
-	return c.Request.Context().Deadline()
+
+	return
 }
 
 // Done returns nil (chan which will wait forever) when c.Request has no Context.
 func (c *Context) Done() <-chan struct{} {
-	if !c.hasRequestContext() {
-		return nil
+	if c.useInternalContext() {
+		c.internalContextMu.RLock()
+		defer c.internalContextMu.RUnlock()
+
+		return c.internalContext.Done()
+	} else if c.hasRequestContext() {
+		return c.Request.Context().Done()
 	}
-	return c.Request.Context().Done()
+
+	return nil
 }
 
 // Err returns nil when c.Request has no Context.
 func (c *Context) Err() error {
-	if !c.hasRequestContext() {
-		return nil
+	if c.useInternalContext() {
+		c.internalContextMu.RLock()
+		defer c.internalContextMu.RUnlock()
+
+		return c.internalContext.Err()
+	} else if c.hasRequestContext() {
+		return c.Request.Context().Err()
 	}
-	return c.Request.Context().Err()
+
+	return nil
 }
 
 // Value returns the value associated with this context for key, or nil
@@ -1464,8 +1545,14 @@ func (c *Context) Value(key any) any {
 			return val
 		}
 	}
-	if !c.hasRequestContext() {
-		return nil
+	if c.useInternalContext() {
+		c.internalContextMu.RLock()
+		defer c.internalContextMu.RUnlock()
+
+		return c.internalContext.Value(key)
+	} else if c.hasRequestContext() {
+		return c.Request.Context().Value(key)
 	}
-	return c.Request.Context().Value(key)
+
+	return nil
 }

context_test.go

@@ -32,6 +32,7 @@ import (
 	testdata "github.com/gin-gonic/gin/testdata/protoexample"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.mongodb.org/mongo-driver/bson"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -1701,6 +1702,23 @@ func TestContextNegotiationWithPROTOBUF(t *testing.T) {
 	assert.Equal(t, "application/x-protobuf", w.Header().Get("Content-Type"))
 }
 
+func TestContextNegotiationWithBSON(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+	c.Request, _ = http.NewRequest(http.MethodPost, "", nil)
+
+	c.Negotiate(http.StatusOK, Negotiate{
+		Offered: []string{MIMEBSON, MIMEXML, MIMEJSON, MIMEYAML, MIMEYAML2},
+		Data:    H{"foo": "bar"},
+	})
+
+	bData, _ := bson.Marshal(H{"foo": "bar"})
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Equal(t, string(bData), w.Body.String())
+	assert.Equal(t, "application/bson", w.Header().Get("Content-Type"))
+}
+
 func TestContextNegotiationNotSupport(t *testing.T) {
 	w := httptest.NewRecorder()
 	c, _ := CreateTestContext(w)
@@ -3221,6 +3239,142 @@ func TestContextWithFallbackValueFromRequestContext(t *testing.T) {
 	}
 }
 
+func TestContextUseInternalContextDeadline(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+		// enable UseInternalContext feature flag
+		c.engine.UseInternalContext = true
+	})
+
+	deadline, ok := c.Deadline()
+	assert.Zero(t, deadline)
+	assert.False(t, ok)
+
+	c2, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+		// enable UseInternalContext feature flag
+		c.engine.UseInternalContext = true
+	})
+
+	d := time.Now().Add(time.Second)
+	ctx, cancel := context.WithDeadline(context.Background(), d)
+	defer cancel()
+	c2.WithInternalContext(ctx)
+	deadline, ok = c2.Deadline()
+	assert.Equal(t, d, deadline)
+	assert.True(t, ok)
+}
+
+func TestContextUseInternalContextDone(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+		// enable UseInternalContext feature flag
+		c.engine.UseInternalContext = true
+	})
+
+	assert.Nil(t, c.Done())
+
+	c2, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+		// enable UseInternalContext feature flag
+		c.engine.UseInternalContext = true
+	})
+
+	ctx, cancel := context.WithCancel(context.Background())
+	c2.WithInternalContext(ctx)
+	cancel()
+	assert.NotNil(t, <-c2.Done())
+}
+
+func TestContextUseInternalContextErr(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+		// enable UseInternalContext feature flag
+		c.engine.UseInternalContext = true
+	})
+
+	require.NoError(t, c.Err())
+
+	c2, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+		// enable UseInternalContext feature flag
+		c.engine.UseInternalContext = true
+	})
+
+	ctx, cancel := context.WithCancel(context.Background())
+	c2.WithInternalContext(ctx)
+	cancel()
+
+	assert.EqualError(t, c2.Err(), context.Canceled.Error())
+}
+
+func TestContextUseInternalContextValue(t *testing.T) {
+	type contextKey string
+
+	tests := []struct {
+		name             string
+		getContextAndKey func() (*Context, any)
+		value            any
+	}{
+		{
+			name: "c with struct context key",
+			getContextAndKey: func() (*Context, any) {
+				type KeyStruct struct{} // https://staticcheck.dev/docs/checks/#SA1029
+				var key KeyStruct
+				c, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+					// enable UseInternalContext feature flag
+					c.engine.UseInternalContext = true
+				})
+				c.WithInternalContext(context.WithValue(context.TODO(), key, "value"))
+				return c, key
+			},
+			value: "value",
+		},
+		{
+			name: "c with struct context key and request context with different value",
+			getContextAndKey: func() (*Context, any) {
+				type KeyStruct struct{} // https://staticcheck.dev/docs/checks/#SA1029
+				var key KeyStruct
+				c, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+					// enable UseInternalContext feature flag
+					c.engine.UseInternalContext = true
+					// enable ContextWithFallback feature flag
+					c.engine.ContextWithFallback = true
+					c.Request, _ = http.NewRequest(http.MethodPost, "/", nil)
+				})
+				c.WithInternalContext(context.WithValue(context.TODO(), key, "value"))
+				c.Request = c.Request.WithContext(context.WithValue(context.TODO(), key, "other value"))
+				return c, key
+			},
+			value: "value",
+		},
+		{
+			name: "c with string context key",
+			getContextAndKey: func() (*Context, any) {
+				c, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+					// enable UseInternalContext feature flag
+					c.engine.UseInternalContext = true
+				})
+				c.WithInternalContext(context.WithValue(context.TODO(), contextKey("key"), "value"))
+				return c, contextKey("key")
+			},
+			value: "value",
+		},
+		{
+			name: "c with background internal context",
+			getContextAndKey: func() (*Context, any) {
+				c, _ := CreateTestContext(httptest.NewRecorder(), func(c *Context) {
+					// enable UseInternalContext feature flag
+					c.engine.UseInternalContext = true
+				})
+				c.WithInternalContext(context.Background())
+				return c, "key"
+			},
+			value: nil,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			c, key := tt.getContextAndKey()
+			assert.Equal(t, tt.value, c.Value(key))
+		})
+	}
+}
+
 func TestContextCopyShouldNotCancel(t *testing.T) {
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
 		w.WriteHeader(http.StatusOK)

gin.go

@@ -169,9 +169,14 @@ type Engine struct {
 	// UseH2C enable h2c support.
 	UseH2C bool
 
-	// ContextWithFallback enable fallback Context.Deadline(), Context.Done(), Context.Err() and Context.Value() when Context.Request.Context() is not nil.
+	// ContextWithFallback enable fallback Context.Deadline(), Context.Done(), Context.Err() and Context.Value()
+	// through Context.Request when Context.Request.Context() is not nil.
 	ContextWithFallback bool
 
+	// UseInternalContext enable fallback Context.Deadline(), Context.Done(), Context.Err()
+	// through InternalContext and supersedes ContextWithFallback
+	UseInternalContext bool
+
 	delims           render.Delims
 	secureJSONPrefix string
 	HTMLRender       render.HTMLRender
@@ -669,6 +674,24 @@ func (engine *Engine) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	c.Request = req
 	c.reset()
 
+	// If we're using internalContext then we need to pass on errors from the request context
+	if c.useInternalContext() {
+		reqCtx := req.Context()
+
+		// we need to get the cancelCause function now, so that we have the function for this request
+		// because the c is a pointer to a Context that will possibly go back into the pool and be reused
+		c.internalContextMu.RLock()
+		cancelCause := c.internalContextCancelCause
+		c.internalContextMu.RUnlock()
+
+		go func() {
+			<-reqCtx.Done()
+			if err := reqCtx.Err(); err != nil {
+				cancelCause(err)
+			}
+		}()
+	}
+
 	engine.handleHTTPRequest(c)
 
 	engine.pool.Put(c)

go.mod

@@ -2,11 +2,13 @@ module github.com/gin-gonic/gin
 
 go 1.24.0
 
+toolchain go1.24.7
+
 require (
 	github.com/bytedance/sonic v1.14.2
 	github.com/gin-contrib/sse v1.1.0
 	github.com/go-playground/validator/v10 v10.28.0
-	github.com/goccy/go-json v0.10.2
+	github.com/goccy/go-json v0.10.5
 	github.com/goccy/go-yaml v1.19.1
 	github.com/json-iterator/go v1.1.12
 	github.com/mattn/go-isatty v0.0.20
@@ -15,10 +17,13 @@ require (
 	github.com/quic-go/quic-go v0.57.1
 	github.com/stretchr/testify v1.11.1
 	github.com/ugorji/go/codec v1.3.1
+	go.mongodb.org/mongo-driver v1.17.7
 	golang.org/x/net v0.47.0
 	google.golang.org/protobuf v1.36.10
 )
 
+require gopkg.in/yaml.v3 v3.0.1 // indirect
+
 require (
 	github.com/bytedance/gopkg v0.1.3 // indirect
 	github.com/bytedance/sonic/loader v0.4.0 // indirect
@@ -30,13 +35,13 @@ require (
 	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
-	github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/quic-go/qpack v0.6.0 // indirect
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
-	golang.org/x/arch v0.20.0 // indirect
+	go.uber.org/mock v0.6.0 // indirect
+	golang.org/x/arch v0.22.0 // indirect
 	golang.org/x/crypto v0.45.0 // indirect
 	golang.org/x/sys v0.38.0 // indirect
 	golang.org/x/text v0.31.0 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -22,8 +22,8 @@ github.com/go-playground/universal-translator v0.18.1 h1:Bcnm0ZwsGyWbCzImXv+pAJn
 github.com/go-playground/universal-translator v0.18.1/go.mod h1:xekY+UJKNuX9WP91TpwSH2VMlDf28Uj24BCp08ZFTUY=
 github.com/go-playground/validator/v10 v10.28.0 h1:Q7ibns33JjyW48gHkuFT91qX48KG0ktULL6FgHdG688=
 github.com/go-playground/validator/v10 v10.28.0/go.mod h1:GoI6I1SjPBh9p7ykNE/yj3fFYbyDOpwMn5KXd+m2hUU=
-github.com/goccy/go-json v0.10.2 h1:CrxCmQqYDkv1z7lO7Wbh2HN93uovUHgrECaO5ZrCXAU=
-github.com/goccy/go-json v0.10.2/go.mod h1:6MelG93GURQebXPDq3khkgXZkazVtN9CRI+MGFi0w8I=
+github.com/goccy/go-json v0.10.5 h1:Fq85nIqj+gXn/S5ahsiTlK3TmC85qgirsdTP/+DeaC4=
+github.com/goccy/go-json v0.10.5/go.mod h1:oq7eo15ShAhp70Anwd5lgX2pLfOS3QCiwU/PULtXL6M=
 github.com/goccy/go-yaml v1.19.1 h1:3rG3+v8pkhRqoQ/88NYNMHYVGYztCOCIZ7UQhu7H+NE=
 github.com/goccy/go-yaml v1.19.1/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
 github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
@@ -41,8 +41,9 @@ github.com/leodido/go-urn v1.4.0 h1:WT9HwE9SGECu3lg4d/dIA+jxlljEa1/ffXKmRjqdmIQ=
 github.com/leodido/go-urn v1.4.0/go.mod h1:bvxc+MVxLKB4z00jd1z+Dvzr47oO32F/QSNjSBOlFxI=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
-github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421 h1:ZqeYNhU3OHLH3mGKHDcjJRFFRrJa6eAM5H+CtDdOsPc=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9Gz0M=
 github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
 github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
@@ -70,10 +71,12 @@ github.com/twitchyliquid64/golang-asm v0.15.1 h1:SU5vSMR7hnwNxj24w34ZyCi/FmDZTkS
 github.com/twitchyliquid64/golang-asm v0.15.1/go.mod h1:a1lVb/DtPvCB8fslRZhAngC2+aY1QWCk3Cedj/Gdt08=
 github.com/ugorji/go/codec v1.3.1 h1:waO7eEiFDwidsBN6agj1vJQ4AG7lh2yqXyOXqhgQuyY=
 github.com/ugorji/go/codec v1.3.1/go.mod h1:pRBVtBSKl77K30Bv8R2P+cLSGaTtex6fsA2Wjqmfxj4=
-go.uber.org/mock v0.5.2 h1:LbtPTcP8A5k9WPXj54PPPbjcI4Y6lhyOZXn+VS7wNko=
-go.uber.org/mock v0.5.2/go.mod h1:wLlUxC2vVTPTaE3UD51E0BGOAElKrILxhVSDYQLld5o=
-golang.org/x/arch v0.20.0 h1:dx1zTU0MAE98U+TQ8BLl7XsJbgze2WnNKF/8tGp/Q6c=
-golang.org/x/arch v0.20.0/go.mod h1:bdwinDaKcfZUGpH09BB7ZmOfhalA8lQdzl62l8gGWsk=
+go.mongodb.org/mongo-driver v1.17.7 h1:a9w+U3Vt67eYzcfq3k/OAv284/uUUkL0uP75VE5rCOU=
+go.mongodb.org/mongo-driver v1.17.7/go.mod h1:Hy04i7O2kC4RS06ZrhPRqj/u4DTYkFDAAccj+rVKqgQ=
+go.uber.org/mock v0.6.0 h1:hyF9dfmbgIX5EfOdasqLsWD6xqpNZlXblLB/Dbnwv3Y=
+go.uber.org/mock v0.6.0/go.mod h1:KiVJ4BqZJaMj4svdfmHM0AUx4NJYO8ZNpPnZn1Z+BBU=
+golang.org/x/arch v0.22.0 h1:c/Zle32i5ttqRXjdLyyHZESLD/bB90DCU1g9l/0YBDI=
+golang.org/x/arch v0.22.0/go.mod h1:dNHoOeKiyja7GTvF9NJS1l3Z2yntpQNzgrjh1cU103A=
 golang.org/x/crypto v0.45.0 h1:jMBrvKuj23MTlT0bQEOBcAE0mjg8mK9RXFhRH6nyF3Q=
 golang.org/x/crypto v0.45.0/go.mod h1:XTGrrkGJve7CYK7J8PEww4aY7gM3qMCElcJQ8n8JdX4=
 golang.org/x/net v0.47.0 h1:Mx+4dIFzqraBXUugkia1OOvlD6LemFo1ALMHjrXDOhY=

render/bson.go

@@ -0,0 +1,34 @@
+// Copyright 2025 Gin Core Team. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package render
+
+import (
+	"net/http"
+
+	"go.mongodb.org/mongo-driver/bson"
+)
+
+// BSON contains the given interface object.
+type BSON struct {
+	Data any
+}
+
+var bsonContentType = []string{"application/bson"}
+
+// Render (BSON) marshals the given interface object and writes data with custom ContentType.
+func (r BSON) Render(w http.ResponseWriter) error {
+	r.WriteContentType(w)
+
+	bytes, err := bson.Marshal(&r.Data)
+	if err == nil {
+		_, err = w.Write(bytes)
+	}
+	return err
+}
+
+// WriteContentType (BSONBuf) writes BSONBuf ContentType.
+func (r BSON) WriteContentType(w http.ResponseWriter) {
+	writeContentType(w, bsonContentType)
+}

render/render_test.go

@@ -19,6 +19,7 @@ import (
 	testdata "github.com/gin-gonic/gin/testdata/protoexample"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.mongodb.org/mongo-driver/bson"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -359,6 +360,31 @@ func TestRenderProtoBufFail(t *testing.T) {
 	require.Error(t, err)
 }
 
+func TestRenderBSON(t *testing.T) {
+	w := httptest.NewRecorder()
+	reps := []int64{int64(1), int64(2)}
+	type mystruct struct {
+		Label string
+		Reps  []int64
+	}
+
+	data := &mystruct{
+		Label: "test",
+		Reps:  reps,
+	}
+
+	(BSON{data}).WriteContentType(w)
+	bsonData, err := bson.Marshal(data)
+	require.NoError(t, err)
+	assert.Equal(t, "application/bson", w.Header().Get("Content-Type"))
+
+	err = (BSON{data}).Render(w)
+
+	require.NoError(t, err)
+	assert.Equal(t, bsonData, w.Body.Bytes())
+	assert.Equal(t, "application/bson", w.Header().Get("Content-Type"))
+}
+
 func TestRenderXML(t *testing.T) {
 	w := httptest.NewRecorder()
 	data := xmlmap{

test_helpers.go

@@ -14,9 +14,12 @@ import (
 // This is useful for tests that need to set up a new Gin engine instance
 // along with a context, for example, to test middleware that doesn't depend on
 // specific routes. The ResponseWriter `w` is used to initialize the context's writer.
-func CreateTestContext(w http.ResponseWriter) (c *Context, r *Engine) {
+func CreateTestContext(w http.ResponseWriter, opts ...func(c *Context)) (c *Context, r *Engine) {
 	r = New()
 	c = r.allocateContext(0)
+	for _, opt := range opts {
+		opt(c)
+	}
 	c.reset()
 	c.writermem.reset(w)
 	return