fix missing initial sync.RWMutex (#2305)

* fix missing initial sync.RWMutex

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

* Add unit testing.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

context.go

@@ -228,6 +228,10 @@ func (c *Context) Error(err error) *Error {
 // Set is used to store a new key/value pair exclusively for this context.
 // It also lazy initializes  c.Keys if it was not used previously.
 func (c *Context) Set(key string, value interface{}) {
+	if c.KeysMutex == nil {
+		c.KeysMutex = &sync.RWMutex{}
+	}
+
 	c.KeysMutex.Lock()
 	if c.Keys == nil {
 		c.Keys = make(map[string]interface{})
@@ -240,6 +244,10 @@ func (c *Context) Set(key string, value interface{}) {
 // Get returns the value for the given key, ie: (value, true).
 // If the value does not exists it returns (nil, false)
 func (c *Context) Get(key string) (value interface{}, exists bool) {
+	if c.KeysMutex == nil {
+		c.KeysMutex = &sync.RWMutex{}
+	}
+
 	c.KeysMutex.RLock()
 	value, exists = c.Keys[key]
 	c.KeysMutex.RUnlock()

context_test.go

@@ -1920,3 +1920,16 @@ func TestRaceParamsContextCopy(t *testing.T) {
 	performRequest(router, "GET", "/name2/api")
 	wg.Wait()
 }
+
+func TestContextWithKeysMutex(t *testing.T) {
+	c := &Context{}
+	c.Set("foo", "bar")
+
+	value, err := c.Get("foo")
+	assert.Equal(t, "bar", value)
+	assert.True(t, err)
+
+	value, err = c.Get("foo2")
+	assert.Nil(t, value)
+	assert.False(t, err)
+}

go.sum

@@ -1,4 +1,5 @@
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/gin-contrib/sse v0.1.0 h1:Y/yl/+YNO8GZSjAhjMsSuLt29uWRFHdHYUb5lYOV9qE=
 github.com/gin-contrib/sse v0.1.0/go.mod h1:RHrZQHXnP2xjPF+u1gW/2HnVO7nvIa9PG3Gm+fLHvGI=