gin.Context with fallback value from gin.Context.Request.Context() (#2751)

* Update tree.go (#2659)

delete more "()"

* updated comments for Get function for params (#2756)

* ci: add github action workflows (#2596)

* ci: add github action workflows

* test: fixed the TestUnixSocket test on windows (#20)

* ci: add github action workflows (#18)

* Remove .travis.yml

* ci: replace GITTER_ROOM_ID and upload coverage every time you go test

* ci: update coverage using codecov/codecov-action@v1

* Merge branch 'master' into github-actions

* repo: replace travis ci to github actions

* ci: add go version 1.16

* fix: go install requires a specific version

* chore(ci): remove go 1.12 support

* chore(ci): remove os windows-latest

Co-authored-by: thinkerou <thinkerou@gmail.com>
Co-authored-by: Bo-Yi Wu <appleboy.tw@gmail.com>

* Setting trusted platform using an enum-like (#2739)

* gin.Context with fallback value from c.Request.Context()

* add test case

Co-authored-by: youzeliang <youzel@126.com>
Co-authored-by: Ashwani <ashwanisharma686@gmail.com>
Co-authored-by: Jeff <laojianzi1994@gmail.com>
Co-authored-by: thinkerou <thinkerou@gmail.com>
Co-authored-by: Bo-Yi Wu <appleboy.tw@gmail.com>
Co-authored-by: Alessandro (Ale) Segala <43508+ItalyPaleAle@users.noreply.github.com>

context.go

@@ -1186,8 +1186,12 @@ func (c *Context) Value(key interface{}) interface{} {
 		return c.Request
 	}
 	if keyAsString, ok := key.(string); ok {
-		val, _ := c.Get(keyAsString)
-		return val
+		if val, exists := c.Get(keyAsString); exists {
+			return val
+		}
 	}
-	return nil
+	if c.Request == nil || c.Request.Context() == nil {
+		return nil
+	}
+	return c.Request.Context().Value(key)
 }

context_test.go

@@ -2057,3 +2057,56 @@ func TestRemoteIPFail(t *testing.T) {
 	assert.Nil(t, ip)
 	assert.False(t, trust)
 }
+
+func TestContextWithFallbackValueFromRequestContext(t *testing.T) {
+	tests := []struct {
+		name             string
+		getContextAndKey func() (*Context, interface{})
+		value            interface{}
+	}{
+		{
+			name: "c with struct context key",
+			getContextAndKey: func() (*Context, interface{}) {
+				var key struct{}
+				c := &Context{}
+				c.Request, _ = http.NewRequest("POST", "/", nil)
+				c.Request = c.Request.WithContext(context.WithValue(context.TODO(), key, "value"))
+				return c, key
+			},
+			value: "value",
+		},
+		{
+			name: "c with string context key",
+			getContextAndKey: func() (*Context, interface{}) {
+				c := &Context{}
+				c.Request, _ = http.NewRequest("POST", "/", nil)
+				c.Request = c.Request.WithContext(context.WithValue(context.TODO(), "key", "value"))
+				return c, "key"
+			},
+			value: "value",
+		},
+		{
+			name: "c with nil http.Request",
+			getContextAndKey: func() (*Context, interface{}) {
+				c := &Context{}
+				return c, "key"
+			},
+			value: nil,
+		},
+		{
+			name: "c with nil http.Request.Context()",
+			getContextAndKey: func() (*Context, interface{}) {
+				c := &Context{}
+				c.Request, _ = http.NewRequest("POST", "/", nil)
+				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))
+		})
+	}
+}