add 'Context.Register/RemoveDependency' for registering dependencies for next handler in the chain from a common iris handler in serve-time

And also, add a Configuration.FireEmptyFormError if end-dev wants to receive an iris.ErrEmptyForm error on missing form data on 'Context.ReadForm/ReadBody'


Former-commit-id: a2713bec77375b2908f1f066a46be4f19e6b7a61

HISTORY.md

@@ -371,6 +371,8 @@ Other Improvements:
 
 ![DBUG routes](https://iris-go.com/images/v12.2.0-dbug2.png?v=0)
 
+- `Context.ReadForm` now can return an `iris.ErrEmptyForm` instead of `nil` when the new `Configuration.FireEmptyFormError`  is true  (or `iris.WithEmptyFormError`) on missing form body to read from.
+
 - `Configuration.EnablePathIntelligence | iris.WithPathIntelligence` to enable path intelligence automatic path redirection on the most closest path (if any), [example]((https://github.com/kataras/iris/blob/master/_examples/routing/intelligence/main.go)
 
 - Enhanced cookie security and management through new `Context.AddCookieOptions` method and new cookie options (look on New Package-level functions section below), [securecookie](https://github.com/kataras/iris/tree/master/_examples/cookies/securecookie) example has been updated.
@@ -409,6 +411,7 @@ New Package-level Variables:
 
 New Context Methods:
 
+- `Context.RegisterDependency(v interface{})` and `Context.RemoveDependency(typ reflect.Type)` to register/remove struct dependencies on serve-time through a middleware.
 - `Context.SetID(id interface{})` and `Context.GetID() interface{}` added to register a custom unique indetifier to the Context, if necessary.
 - `Context.GetDomain() string` returns the domain.
 - `Context.AddCookieOptions(...CookieOption)` adds options for `SetCookie`, `SetCookieKV, UpsertCookie` and `RemoveCookie` methods for the current request.

_examples/README.md

@@ -164,6 +164,7 @@
         * [Middleware](dependency-injection/basic/middleware/main.go)
     * [Sessions](dependency-injection/sessions/main.go)
     * [Smart Contract](dependency-injection/smart-contract/main.go)
+    * [JWT](dependency-injection/jwt/main.go)
 * MVC
     * [Overview - Repository and Service layers](mvc/overview)
     * [Login - Repository and Service layers](mvc/login)

_examples/dependency-injection/jwt/main.go

@@ -37,10 +37,13 @@ func register(api *iris.APIContainer) {
 	// 		ctx.StopWithStatus(iris.StatusUnauthorized)
 	// 		return nil
 	// 	}
-
+	//
 	// 	token := j.Get(ctx)
 	// 	return token
 	// })
+	// ^ You can do the same with MVC too, as the container is shared and works
+	// the same way in both functions-as-handlers and structs-as-controllers.
+	//
 	// api.Get("/", verifiedWithBindedTokenPage)
 }
 

configuration.go

@@ -262,6 +262,13 @@ var WithoutBodyConsumptionOnUnmarshal = func(app *Application) {
 	app.config.DisableBodyConsumptionOnUnmarshal = true
 }
 
+// WithEmptyFormError enables the setting `FireEmptyFormError`.
+//
+// See `Configuration`.
+var WithEmptyFormError = func(app *Application) {
+	app.config.FireEmptyFormError = true
+}
+
 // WithoutAutoFireStatusCode disables the AutoFireStatusCode setting.
 //
 // See `Configuration`.
@@ -837,6 +844,9 @@ type Configuration struct {
 	// The body will not be changed and existing data before the
 	// context.UnmarshalBody/ReadJSON/ReadXML will be not consumed.
 	DisableBodyConsumptionOnUnmarshal bool `json:"disableBodyConsumptionOnUnmarshal,omitempty" yaml:"DisableBodyConsumptionOnUnmarshal" toml:"DisableBodyConsumptionOnUnmarshal"`
+	// FireEmptyFormError returns if set to tue true then the `context.ReadBody/ReadForm`
+	//  will return an `iris.ErrEmptyForm` on empty request form data.
+	FireEmptyFormError bool `json:"fireEmptyFormError,omitempty" yaml:"FireEmptyFormError" yaml:"FireEmptyFormError"`
 
 	// DisableAutoFireStatusCode if true then it turns off the http error status code handler automatic execution
 	// from (`context.StatusCodeNotSuccessful`, defaults to < 200 || >= 400).
@@ -1021,6 +1031,13 @@ func (c Configuration) GetDisableBodyConsumptionOnUnmarshal() bool {
 	return c.DisableBodyConsumptionOnUnmarshal
 }
 
+// GetFireEmptyFormError returns the Configuration.FireEmptyFormError value.
+// If true then the `context.ReadBody/ReadForm` will return an `iris.ErrEmptyForm`
+// on empty request form data.
+func (c Configuration) GetFireEmptyFormError() bool {
+	return c.DisableBodyConsumptionOnUnmarshal
+}
+
 // GetDisableAutoFireStatusCode returns the Configuration#DisableAutoFireStatusCode.
 // Returns true when the http error status code handler automatic execution turned off.
 func (c Configuration) GetDisableAutoFireStatusCode() bool {
@@ -1190,6 +1207,10 @@ func WithConfiguration(c Configuration) Configurator {
 			main.DisableBodyConsumptionOnUnmarshal = v
 		}
 
+		if v := c.FireEmptyFormError; v {
+			main.FireEmptyFormError = v
+		}
+
 		if v := c.DisableAutoFireStatusCode; v {
 			main.DisableAutoFireStatusCode = v
 		}
@@ -1261,6 +1282,7 @@ func DefaultConfiguration() Configuration {
 		ForceLowercaseRouting:             false,
 		FireMethodNotAllowed:              false,
 		DisableBodyConsumptionOnUnmarshal: false,
+		FireEmptyFormError:                false,
 		DisableAutoFireStatusCode:         false,
 		TimeFormat:                        "Mon, 02 Jan 2006 15:04:05 GMT",
 		Charset:                           "utf-8",

context/configuration.go

@@ -53,7 +53,10 @@ type ConfigurationReadOnly interface {
 	// The body will not be changed and existing data before the
 	// context.UnmarshalBody/ReadJSON/ReadXML will be not consumed.
 	GetDisableBodyConsumptionOnUnmarshal() bool
-
+	// GetFireEmptyFormError returns the Configuration.FireEmptyFormError value.
+	// If true then the `context.ReadBody/ReadForm` will return an `iris.ErrEmptyForm`
+	// on empty request form data.
+	GetFireEmptyFormError() bool
 	// GetDisableAutoFireStatusCode returns the configuration.DisableAutoFireStatusCode.
 	// Returns true when the http error status code handler automatic execution turned off.
 	GetDisableAutoFireStatusCode() bool

context/context.go

@@ -662,6 +662,9 @@ type Context interface {
 	// It supports any kind of type, including custom structs.
 	// It will return nothing if request data are empty.
 	// The struct field tag is "form".
+	// Note that it will return nil error on empty form data if `Configuration.FireEmptyFormError`
+	// is false (as defaulted) in this case the caller should check the pointer to
+	// see if something was actually binded.
 	//
 	// Example: https://github.com/kataras/iris/blob/master/_examples/http_request/read-form/main.go
 	ReadForm(formObject interface{}) error
@@ -1124,6 +1127,20 @@ type Context interface {
 	// Controller returns a reflect Value of the custom Controller from which this handler executed.
 	// It will return a Kind() == reflect.Invalid if the handler was not executed from within a controller.
 	Controller() reflect.Value
+	// RegisterDependency registers a struct dependency at serve-time
+	// for the next handler in the chain. One value per type.
+	// Note that it's highly recommended to register
+	// your dependencies before server ran
+	// through APIContainer(app.ConfigureContainer) or MVC(mvc.New)
+	// in sake of minimum performance cost.
+	//
+	// See `UnRegisterDependency` too.
+	RegisterDependency(v interface{})
+	// UnRegisterDependency removes a dependency based on its type.
+	// Reports whether a dependency with that type was found and removed successfully.
+	//
+	// See `RegisterDependency` too.
+	UnRegisterDependency(typ reflect.Type) bool
 
 	// Application returns the iris app instance which belongs to this context.
 	// Worth to notice that this function returns an interface
@@ -2890,15 +2907,25 @@ func (ctx *context) ReadYAML(outPtr interface{}) error {
 // A shortcut for the `schema#IsErrPath`.
 var IsErrPath = schema.IsErrPath
 
+// ErrEmptyForm is returned by `context#ReadForm` and `context#ReadBody`
+// when it should read data from a request form data but there is none.
+var ErrEmptyForm = errors.New("empty form")
+
 // ReadForm binds the request body of a form to the "formObject".
 // It supports any kind of type, including custom structs.
 // It will return nothing if request data are empty.
 // The struct field tag is "form".
+// Note that it will return nil error on empty form data if `Configuration.FireEmptyFormError`
+// is false (as defaulted) in this case the caller should check the pointer to
+// see if something was actually binded.
 //
 // Example: https://github.com/kataras/iris/blob/master/_examples/http_request/read-form/main.go
 func (ctx *context) ReadForm(formObject interface{}) error {
 	values := ctx.FormValues()
 	if len(values) == 0 {
+		if ctx.Application().ConfigurationReadOnly().GetFireEmptyFormError() {
+			return ErrEmptyForm
+		}
 		return nil
 	}
 
@@ -2984,6 +3011,7 @@ func (ctx *context) ReadBody(ptr interface{}) error {
 			// try read from query.
 			return ctx.ReadQuery(ptr)
 		}
+
 		// otherwise default to JSON.
 		return ctx.ReadJSON(ptr)
 	}
@@ -5424,6 +5452,61 @@ func (ctx *context) Controller() reflect.Value {
 	return emptyValue
 }
 
+// DependenciesContextKey is the context key for the context's value
+// to keep the serve-time static dependencies raw values.
+const DependenciesContextKey = "iris.dependencies"
+
+// DependenciesMap is the type which context serve-time
+// struct dependencies are stored with.
+type DependenciesMap map[reflect.Type]reflect.Value
+
+// RegisterDependency registers a struct dependency at serve-time
+// for the next handler in the chain. One value per type.
+// Note that it's highly recommended to register
+// your dependencies before server ran
+// through APIContainer(app.ConfigureContainer) or MVC(mvc.New)
+// in sake of minimum performance cost.
+func (ctx *context) RegisterDependency(v interface{}) {
+	if v == nil {
+		return
+	}
+
+	val, ok := v.(reflect.Value)
+	if !ok {
+		val = reflect.ValueOf(v)
+	}
+
+	cv := ctx.Values().Get(DependenciesContextKey)
+	if cv != nil {
+		m, ok := cv.(DependenciesMap)
+		if !ok {
+			return
+		}
+
+		m[val.Type()] = val
+		return
+	}
+
+	ctx.Values().Set(DependenciesContextKey, DependenciesMap{
+		val.Type(): val,
+	})
+}
+
+// UnRegisterDependency removes a dependency based on its type.
+// Reports whether a dependency with that type was found and removed successfully.
+func (ctx *context) UnRegisterDependency(typ reflect.Type) bool {
+	cv := ctx.Values().Get(DependenciesContextKey)
+	if cv != nil {
+		m, ok := cv.(DependenciesMap)
+		if ok {
+			delete(m, typ)
+			return true
+		}
+	}
+
+	return false
+}
+
 // Application returns the iris app instance which belongs to this context.
 // Worth to notice that this function returns an interface
 // of the Application, which contains methods that are safe

hero/binding.go

@@ -323,6 +323,14 @@ func payloadBinding(index int, typ reflect.Type) *binding {
 			Handle: func(ctx context.Context, input *Input) (newValue reflect.Value, err error) {
 				wasPtr := input.Type.Kind() == reflect.Ptr
 
+				if serveDepsV := ctx.Values().Get(context.DependenciesContextKey); serveDepsV != nil {
+					if serveDeps, ok := serveDepsV.(context.DependenciesMap); ok {
+						if newValue, ok = serveDeps[typ]; ok {
+							return
+						}
+					}
+				}
+
 				newValue = reflect.New(indirectType(input.Type))
 				ptr := newValue.Interface()
 				err = ctx.ReadBody(ptr)

hero/handler.go

@@ -75,7 +75,8 @@ func makeHandler(fn interface{}, c *Container, paramsCount int) context.Handler
 	}
 
 	v := valueOf(fn)
-	numIn := v.Type().NumIn()
+	typ := v.Type()
+	numIn := typ.NumIn()
 
 	bindings := getBindingsForFunc(v, c.Dependencies, paramsCount)
 

hero/handler_test.go

@@ -129,17 +129,18 @@ func TestBindFunctionAsFunctionInputArgument(t *testing.T) {
 func TestPayloadBinding(t *testing.T) {
 	h := New()
 
-	postHandler := h.Handler(func(input *testUserStruct /* ptr */) string {
+	ptrHandler := h.Handler(func(input *testUserStruct /* ptr */) string {
 		return input.Username
 	})
 
-	postHandler2 := h.Handler(func(input testUserStruct) string {
+	valHandler := h.Handler(func(input testUserStruct) string {
 		return input.Username
 	})
 
 	app := iris.New()
-	app.Post("/", postHandler)
+	app.Get("/", ptrHandler)
-	app.Post("/2", postHandler2)
+	app.Post("/", ptrHandler)
+	app.Post("/2", valHandler)
 
 	e := httptest.New(t, app)
 
@@ -152,8 +153,10 @@ func TestPayloadBinding(t *testing.T) {
 	// FORM (multipart)
 	e.POST("/").WithMultipart().WithFormField("username", "makis").Expect().Status(httptest.StatusOK).Body().Equal("makis")
 
-	// URL query.
+	// POST URL query.
 	e.POST("/").WithQuery("username", "makis").Expect().Status(httptest.StatusOK).Body().Equal("makis")
+	// GET URL query.
+	e.GET("/").WithQuery("username", "makis").Expect().Status(httptest.StatusOK).Body().Equal("makis")
 }
 
 /* Author's notes:
@@ -241,3 +244,44 @@ func TestHandlerPathParams(t *testing.T) {
 		testReq.Expect().Status(httptest.StatusOK).Body().Equal("42")
 	}
 }
+
+func TestRegisterDependenciesFromContext(t *testing.T) {
+	// Tests serve-time struct dependencies through a common Iris middleware.
+	app := iris.New()
+	app.Use(func(ctx iris.Context) {
+		ctx.RegisterDependency(testUserStruct{Username: "kataras"})
+		ctx.Next()
+	})
+	app.Use(func(ctx iris.Context) {
+		ctx.RegisterDependency(&testServiceImpl{prefix: "say"})
+		ctx.Next()
+	})
+
+	app.ConfigureContainer(func(api *iris.APIContainer) {
+		api.Get("/", func(u testUserStruct) string {
+			return u.Username
+		})
+
+		api.Get("/service", func(s *testServiceImpl) string {
+			return s.Say("hello")
+		})
+
+		// Note: we are not allowed to pass the service as an interface here
+		// because the container will, correctly, panic because it will expect
+		// a dependency to be registered before server ran.
+		api.Get("/both", func(s *testServiceImpl, u testUserStruct) string {
+			return s.Say(u.Username)
+		})
+
+		api.Get("/non", func() string {
+			return "nothing"
+		})
+	})
+
+	e := httptest.New(t, app)
+
+	e.GET("/").Expect().Status(httptest.StatusOK).Body().Equal("kataras")
+	e.GET("/service").Expect().Status(httptest.StatusOK).Body().Equal("say hello")
+	e.GET("/both").Expect().Status(httptest.StatusOK).Body().Equal("say kataras")
+	e.GET("/non").Expect().Status(httptest.StatusOK).Body().Equal("nothing")
+}

iris.go

@@ -575,6 +575,11 @@ var (
 	//
 	// A shortcut for the `context#IsErrPath`.
 	IsErrPath = context.IsErrPath
+	// ErrEmptyForm is the type error which API users can make use of
+	// to check if a form was empty on `Context.ReadForm`.
+	//
+	// A shortcut for the `context#ErrEmptyForm`.
+	ErrEmptyForm = context.ErrEmptyForm
 	// NewProblem returns a new Problem.
 	// Head over to the `Problem` type godoc for more.
 	//