breaking change: remove static field context.DefaultMaxMemory and replace it with a better configurable option inside the main configuration, this makes things clear and it allows users to prevent any unwanted client behavior without digging into the framework's internals

Former-commit-id: 875afd32acfab8abdea15ce9be2ad384eb6bad5e

configuration.go

@@ -315,6 +315,18 @@ func WithCharset(charset string) Configurator {
 	}
 }
 
+// WithPostMaxMemory sets the maximum post data size
+// that a client can send to the server, this differs
+// from the overral request body size which can be modified
+// by the `context#SetMaxRequestBodySize` or `iris#LimitRequestBodySize.
+//
+// Defaults to 32MB or 32 << 20 if you prefer.
+func WithPostMaxMemory(limit int64) Configurator {
+	return func(app *Application) {
+		app.config.PostMaxMemory = limit
+	}
+}
+
 // WithRemoteAddrHeader enables or adds a new or existing request header name
 // that can be used to validate the client's real IP.
 //
@@ -463,6 +475,13 @@ type Configuration struct {
 	// Defaults to "UTF-8".
 	Charset string `json:"charset,omitempty" yaml:"Charset" toml:"Charset"`
 
+	// PostMaxMemory sets the maximum post data size
+	// that a client can send to the server, this differs
+	// from the overral request body size which can be modified
+	// by the `context#SetMaxRequestBodySize` or `iris#LimitRequestBodySize.
+	//
+	// Defaults to 32MB or 32 << 20 if you prefer.
+	PostMaxMemory int64 `json:"postMaxMemory" yaml:"PostMaxMemory" toml:"PostMaxMemory"`
 	//  +----------------------------------------------------+
 	//  | Context's keys for values used on various featuers |
 	//  +----------------------------------------------------+
@@ -579,6 +598,16 @@ func (c Configuration) GetCharset() string {
 	return c.Charset
 }
 
+// GetPostMaxMemory returns the maximum configured post data size
+// that a client can send to the server, this differs
+// from the overral request body size which can be modified
+// by the `context#SetMaxRequestBodySize` or `iris#LimitRequestBodySize.
+//
+// Defaults to 32MB or 32 << 20 if you prefer.
+func (c Configuration) GetPostMaxMemory() int64 {
+	return c.PostMaxMemory
+}
+
 // GetTranslateFunctionContextKey returns the configuration's TranslateFunctionContextKey value,
 // used for i18n.
 func (c Configuration) GetTranslateFunctionContextKey() string {
@@ -684,6 +713,10 @@ func WithConfiguration(c Configuration) Configurator {
 			main.Charset = v
 		}
 
+		if v := c.PostMaxMemory; v > 0 {
+			main.PostMaxMemory = v
+		}
+
 		if v := c.TranslateFunctionContextKey; v != "" {
 			main.TranslateFunctionContextKey = v
 		}
@@ -733,10 +766,17 @@ func DefaultConfiguration() Configuration {
 		DisableAutoFireStatusCode:         false,
 		TimeFormat:                        "Mon, Jan 02 2006 15:04:05 GMT",
 		Charset:                           "UTF-8",
-		TranslateFunctionContextKey:       "iris.translate",
-		TranslateLanguageContextKey:       "iris.language",
-		ViewLayoutContextKey:              "iris.viewLayout",
-		ViewDataContextKey:                "iris.viewData",
+
+		// PostMaxMemory is for post body max memory.
+		//
+		// The request body the size limit
+		// can be set by the middleware `LimitRequestBodySize`
+		// or `context#SetMaxRequestBodySize`.
+		PostMaxMemory:               32 << 20, // 32MB
+		TranslateFunctionContextKey: "iris.translate",
+		TranslateLanguageContextKey: "iris.language",
+		ViewLayoutContextKey:        "iris.viewLayout",
+		ViewDataContextKey:          "iris.viewData",
 		RemoteAddrHeaders: map[string]bool{
 			"X-Real-Ip":        false,
 			"X-Forwarded-For":  false,

context/configuration.go

@@ -54,6 +54,14 @@ type ConfigurationReadOnly interface {
 	// used for templates and the rest of the responses.
 	GetCharset() string
 
+	// GetPostMaxMemory returns the maximum configured post data size
+	// that a client can send to the server, this differs
+	// from the overral request body size which can be modified
+	// by the `context#SetMaxRequestBodySize` or `iris#LimitRequestBodySize.
+	//
+	// Defaults to 32MB or 32 << 20 if you prefer.
+	GetPostMaxMemory() int64
+
 	// GetTranslateLanguageContextKey returns the configuration's TranslateFunctionContextKey value,
 	// used for i18n.
 	GetTranslateFunctionContextKey() string

context/context.go

@@ -486,7 +486,7 @@ type Context interface {
 	// FormValues returns the parsed form data, including both the URL
 	// field's query parameters and the POST or PUT form data.
 	//
-	// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultMaxMemory`.
+	// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultPostMaxMemory`.
 	//
 	// NOTE: A check for nil is necessary.
 	FormValues() map[string][]string
@@ -540,11 +540,11 @@ type Context interface {
 	// PostValues returns all the parsed form data from POST, PATCH,
 	// or PUT body parameters based on a "name" as a string slice.
 	//
-	// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultMaxMemory`.
+	// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultPostMaxMemory`.
 	PostValues(name string) []string
 	// FormFile returns the first uploaded file that received from the client.
 	//
-	// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultMaxMemory`.
+	// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultPostMaxMemory`.
 	FormFile(key string) (multipart.File, *multipart.FileHeader, error)
 
 	//  +------------------------------------------------------------+
@@ -668,7 +668,6 @@ type Context interface {
 	//
 	// Example: https://github.com/kataras/iris/tree/master/_examples/view/context-view-data/
 	ViewLayout(layoutTmplFile string)
-
 	// ViewData saves one or more key-value pair in order to be passed if and when .View
 	// is being called afterwards, in the same request.
 	// Useful when need to set or/and change template data from previous hanadlers in the chain.
@@ -688,7 +687,6 @@ type Context interface {
 	//
 	// Example: https://github.com/kataras/iris/tree/master/_examples/view/context-view-data/
 	ViewData(key string, value interface{})
-
 	// GetViewData returns the values registered by `context#ViewData`.
 	// The return value is `map[string]interface{}`, this means that
 	// if a custom struct registered to ViewData then this function
@@ -699,16 +697,20 @@ type Context interface {
 	// Similarly to `viewData := ctx.Values().Get("iris.viewData")` or
 	// `viewData := ctx.Values().Get(ctx.Application().ConfigurationReadOnly().GetViewDataContextKey())`.
 	GetViewData() map[string]interface{}
-
-	// View renders templates based on the adapted view engines.
-	// First argument accepts the filename, relative to the view engine's Directory,
+	// View renders a template based on the registered view engine(s).
+	// First argument accepts the filename, relative to the view engine's Directory and Extension,
 	// i.e: if directory is "./templates" and want to render the "./templates/users/index.html"
 	// then you pass the "users/index.html" as the filename argument.
 	//
-	// Look: .ViewData and .ViewLayout too.
+	// The second optional argument can receive a single "view model"
+	// that will be binded to the view template if it's not nil,
+	// otherwise it will check for previous view data stored by the `ViewData`
+	// even if stored at any previous handler(middleware) for the same request.
 	//
-	// Examples: https://github.com/kataras/iris/tree/master/_examples/view/
-	View(filename string) error
+	// Look .ViewData` and .ViewLayout too.
+	//
+	// Examples: https://github.com/kataras/iris/tree/master/_examples/view
+	View(filename string, optionalViewModel ...interface{}) error
 
 	// Binary writes out the raw bytes as binary data.
 	Binary(data []byte) (int, error)
@@ -1600,7 +1602,7 @@ func (ctx *context) FormValue(name string) string {
 // FormValues returns the parsed form data, including both the URL
 // field's query parameters and the POST or PUT form data.
 //
-// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultMaxMemory`.
+// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultPostMaxMemory`.
 //
 // NOTE: A check for nil is necessary.
 func (ctx *context) FormValues() map[string][]string {
@@ -1624,7 +1626,7 @@ func (ctx *context) form() (form map[string][]string, found bool) {
 	// therefore we don't need to call it here, although it doesn't hurt.
 	// After one call to ParseMultipartForm or ParseForm,
 	// subsequent calls have no effect, are idempotent.
-	ctx.request.ParseMultipartForm(DefaultMaxMemory)
+	ctx.request.ParseMultipartForm(ctx.Application().ConfigurationReadOnly().GetPostMaxMemory())
 
 	if form := ctx.request.Form; len(form) > 0 {
 		return form, true
@@ -1733,19 +1735,10 @@ func (ctx *context) PostValueBool(name string) (bool, error) {
 	return strconv.ParseBool(ctx.PostValue(name))
 }
 
-const (
-	// DefaultMaxMemory is the default value
-	// for body max memory, defaults to
-	// 32MB.
-	// Can be also changed by the middleware `LimitRequestBodySize`
-	// or `context#SetMaxRequestBodySize`.
-	DefaultMaxMemory = 32 << 20 // 32 MB
-)
-
 // PostValues returns all the parsed form data from POST, PATCH,
 // or PUT body parameters based on a "name" as a string slice.
 //
-// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultMaxMemory`.
+// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultPostMaxMemory`.
 func (ctx *context) PostValues(name string) []string {
 	ctx.form()
 	return ctx.request.PostForm[name]
@@ -1753,11 +1746,41 @@ func (ctx *context) PostValues(name string) []string {
 
 // FormFile returns the first uploaded file that received from the client.
 //
-// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultMaxMemory`.
+// The default form's memory maximum size is 32MB, it can be changed by the `context#DefaultPostMaxMemory`.
 func (ctx *context) FormFile(key string) (multipart.File, *multipart.FileHeader, error) {
 	return ctx.request.FormFile(key)
 }
 
+// Copiable is the interface which should be completed
+// by files or not that intend to be used inside the `context#CopyFile`.
+// This interface allows testing file uploads to your http test as well.
+//
+// See `CopyFile` for more.
+type Copiable interface {
+	Open() (io.ReadCloser, error)
+}
+
+// CopyFile copies a `context#Copiable` "file", that can be acquired by a `context.FormFile`
+// as well, to the "dest".
+//
+// Returns the copied length as int64 and
+// an error if file is not exist, or new file can't be created or closed at the end.
+func CopyFile(file Copiable, dest string) (int64, error) {
+	src, err := file.Open()
+	if err != nil {
+		return 0, err
+	}
+	defer src.Close()
+
+	out, err := os.Create(dest)
+	if err != nil {
+		return 0, err
+	}
+	defer out.Close()
+
+	return io.Copy(out, src)
+}
+
 // Redirect sends a redirect response to the client
 // to a specific url or relative path.
 // accepts 2 parameters string and an optional int
@@ -2163,20 +2186,32 @@ func (ctx *context) GetViewData() map[string]interface{} {
 	return nil
 }
 
-// View renders templates based on the adapted view engines.
-// First argument accepts the filename, relative to the view engine's Directory,
+// View renders a template based on the registered view engine(s).
+// First argument accepts the filename, relative to the view engine's Directory and Extension,
 // i.e: if directory is "./templates" and want to render the "./templates/users/index.html"
 // then you pass the "users/index.html" as the filename argument.
 //
-// Look: .ViewData and .ViewLayout too.
+// The second optional argument can receive a single "view model"
+// that will be binded to the view template if it's not nil,
+// otherwise it will check for previous view data stored by the `ViewData`
+// even if stored at any previous handler(middleware) for the same request.
 //
-// Examples: https://github.com/kataras/iris/tree/master/_examples/view/
-func (ctx *context) View(filename string) error {
+// Look .ViewData and .ViewLayout too.
+//
+// Examples: https://github.com/kataras/iris/tree/master/_examples/view
+func (ctx *context) View(filename string, optionalViewModel ...interface{}) error {
 	ctx.ContentType(ContentHTMLHeaderValue)
 	cfg := ctx.Application().ConfigurationReadOnly()
 
 	layout := ctx.values.GetString(cfg.GetViewLayoutContextKey())
-	bindingData := ctx.values.Get(cfg.GetViewDataContextKey())
+
+	var bindingData interface{}
+	if len(optionalViewModel) > 0 {
+		// a nil can override the existing data or model sent by `ViewData`.
+		bindingData = optionalViewModel[0]
+	} else {
+		bindingData = ctx.values.Get(cfg.GetViewDataContextKey())
+	}
 
 	err := ctx.Application().View(ctx.writer, filename, layout, bindingData)
 	if err != nil {

doc.go

@@ -1569,7 +1569,7 @@ for this controller, uncomment these if you want:
     func (c *ExampleController) Options() {}
     func (c *ExampleController) Trace() {}
 */
-
+//
 /*
     func (c *ExampleController) All() {}
     //        OR

iris.go

@@ -311,6 +311,12 @@ var (
 	//
 	// Examples: https://github.com/kataras/iris/tree/master/_examples/file-server
 	StaticEmbeddedHandler = router.StaticEmbeddedHandler
+	// CopyFile copies a `context#Copiable` "file", that can be acquired by a `context.FormFile`
+	// as well, to the "dest".
+	//
+	// Returns the copied length as int64 and
+	// an error if file is not exist, or new file can't be created or closed at the end.
+	CopyFile = context.CopyFile
 	// Gzip is a middleware which enables writing
 	// using gzip compression, if client supports.
 	//