tonic: bind keys from gin.Context

go.mod

@@ -6,8 +6,15 @@ require (
 	github.com/go-playground/validator/v10 v10.19.0
 	github.com/google/uuid v1.6.0
 	github.com/juju/errors v0.0.0-20200330140219-3fe23663418f
-	github.com/mattn/go-sqlite3 v1.14.22
+	github.com/juju/testing v0.0.0-20210302031854-2c7ee8570c07 // indirect
+	github.com/lib/pq v1.9.0 // indirect
+	github.com/mattn/go-sqlite3 v2.0.3+incompatible
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/pires/go-proxyproto v0.7.0
+	github.com/poy/onpar v1.1.2 // indirect
+	github.com/ziutek/mymysql v1.5.4 // indirect
+	golang.org/x/sys v0.17.0 // indirect
 	sigs.k8s.io/yaml v1.4.0
 )
 
@@ -21,22 +28,15 @@ require (
 	github.com/go-sql-driver/mysql v1.5.0 // indirect
 	github.com/goccy/go-json v0.10.2 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/juju/testing v0.0.0-20210302031854-2c7ee8570c07 // indirect
 	github.com/klauspost/cpuid/v2 v2.2.4 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
-	github.com/lib/pq v1.9.0 // indirect
 	github.com/mattn/go-isatty v0.0.19 // indirect
-	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
-	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/pelletier/go-toml/v2 v2.0.8 // indirect
-	github.com/poy/onpar v1.1.2 // indirect
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/ugorji/go/codec v1.2.12 // indirect
-	github.com/ziutek/mymysql v1.5.4 // indirect
 	golang.org/x/arch v0.3.0 // indirect
 	golang.org/x/crypto v0.19.0 // indirect
 	golang.org/x/net v0.21.0 // indirect
-	golang.org/x/sys v0.17.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
 	google.golang.org/protobuf v1.30.0 // indirect
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect

go.sum

@@ -138,8 +138,8 @@ github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hd
 github.com/mattn/go-isatty v0.0.11/go.mod h1:PhnuNfih5lzO57/f3n+odYbM4JtupLOxQOAqxQCu2WE=
 github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
 github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
-github.com/mattn/go-sqlite3 v1.14.22 h1:2gZY6PC6kBnID23Tichd1K+Z0oS6nE/XwU+Vz/5o4kU=
-github.com/mattn/go-sqlite3 v1.14.22/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=
+github.com/mattn/go-sqlite3 v2.0.3+incompatible h1:gXHsfypPkaMZrKbD5209QV9jbUTJKjyR5WD3HYQSd+U=
+github.com/mattn/go-sqlite3 v2.0.3+incompatible/go.mod h1:FPy6KqzDD04eiIsT53CuJW3U88zkxoIYsOqkbpncsNc=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=

tonic/handler.go

@@ -91,6 +91,11 @@ func Handler(h interface{}, status int, options ...func(*Route)) gin.HandlerFunc
 				handleError(c, err)
 				return
 			}
+			// Bind context-keys
+			if err := bind(c, input, ContextTag, extractContext); err != nil {
+				handleError(c, err)
+				return
+			}
 			// validating query and path inputs if they have a validate tag
 			initValidator()
 			args = append(args, input)

tonic/tonic.go

@@ -27,6 +27,7 @@ const (
 	QueryTag      = "query"
 	PathTag       = "path"
 	HeaderTag     = "header"
+	ContextTag    = "context"
 	EnumTag       = "enum"
 	RequiredTag   = "required"
 	DefaultTag    = "default"
@@ -354,6 +355,30 @@ func extractHeader(c *gin.Context, tag string) (string, []string, error) {
 	return name, []string{header}, nil
 }
 
+// extractContext is an extractor that operates on the gin.Context
+// of a request.
+func extractContext(c *gin.Context, tag string) (string, []string, error) {
+	name, required, defaultVal, err := parseTagKey(tag)
+	if err != nil {
+		return "", nil, err
+	}
+	context := c.GetString(name)
+
+	// XXX: deprecated, use of "default" tag is preferred
+	if context == "" && defaultVal != "" {
+		return name, []string{defaultVal}, nil
+	}
+	// XXX: deprecated, use of "validate" tag is preferred
+	if required && context == "" {
+		return "", nil, fmt.Errorf("missing header parameter: %s", name)
+	}
+
+	if len(context) == 0 {
+		return name, []string{}, nil
+	}
+	return name, []string{context}, nil
+}
+
 // Public signature does not expose "required" and "default" because
 // they are deprecated in favor of the "validate" and "default" tags
 func parseTagKey(tag string) (string, bool, string, error) {

tonic/tonic_test.go

@@ -28,13 +28,31 @@ func TestMain(m *testing.M) {
 	tonic.SetErrorHook(errorHook)
 
 	g := gin.Default()
+
+	// for context test
+	g.Use(func(c *gin.Context) {
+		if c.FullPath() == "/context" {
+			if val, ok := c.GetQuery("param"); ok {
+				c.Set("param", val)
+			}
+			if val, ok := c.GetQuery("param-optional"); ok {
+				c.Set("param-optional", val)
+			}
+			if val, ok := c.GetQuery("param-optional-validated"); ok {
+				c.Set("param-optional-validated", val)
+			}
+		}
+		c.Next()
+	})
+
 	g.GET("/simple", tonic.Handler(simpleHandler, 200))
 	g.GET("/scalar", tonic.Handler(scalarHandler, 200))
 	g.GET("/error", tonic.Handler(errorHandler, 200))
 	g.GET("/path/:param", tonic.Handler(pathHandler, 200))
 	g.GET("/query", tonic.Handler(queryHandler, 200))
 	g.GET("/query-old", tonic.Handler(queryHandlerOld, 200))
 	g.POST("/body", tonic.Handler(bodyHandler, 200))
+	g.GET("/context", tonic.Handler(contextHandler, 200))
 
 	r = g
 
@@ -130,6 +148,17 @@ func TestBody(t *testing.T) {
 	tester.Run()
 }
 
+func TestContext(t *testing.T) {
+	tester := iffy.NewTester(t, r)
+
+	tester.AddCall("context", "GET", "/context?param=foo", ``).Checkers(iffy.ExpectStatus(200), expectString("param", "foo"))
+	tester.AddCall("context", "GET", "/context", ``).Checkers(iffy.ExpectStatus(400))
+	tester.AddCall("context", "GET", "/context?param=foo&param-optional=bar", ``).Checkers(iffy.ExpectStatus(200), expectString("param-optional", "bar"))
+	tester.AddCall("context", "GET", "/context?param=foo&param-optional-validated=foo", ``).Checkers(iffy.ExpectStatus(200), expectString("param-optional-validated", "foo"))
+
+	tester.Run()
+}
+
 func errorHandler(c *gin.Context) error {
 	return errors.New("error")
 }
@@ -199,6 +228,16 @@ func bodyHandler(c *gin.Context, in *bodyIn) (*bodyIn, error) {
 	return in, nil
 }
 
+type ContextIn struct {
+	Param                  string `context:"param" json:"param" validate:"required"`
+	ParamOptional          string `context:"param-optional" json:"param-optional"`
+	ValidatedParamOptional string `context:"param-optional-validated" json:"param-optional-validated" validate:"eq=|eq=foo|gt=10"`
+}
+
+func contextHandler(c *gin.Context, in *ContextIn) (*ContextIn, error) {
+	return in, nil
+}
+
 func expectEmptyBody(r *http.Response, body string, obj interface{}) error {
 	if len(body) != 0 {
 		return fmt.Errorf("Body '%s' should be empty", body)