package echo import ( "bytes" "encoding/xml" "fmt" "io" "mime/multipart" "net" "net/http" "net/url" "strings" "sync" ) type ( // Context represents the context of the current HTTP request. It holds request and // response objects, path, path parameters, data and registered handler. Context interface { // Request returns `*http.Request`. Request() *http.Request // SetRequest sets `*http.Request`. SetRequest(r *http.Request) // SetResponse sets `*Response`. SetResponse(r *Response) // Response returns `*Response`. Response() *Response // IsTLS returns true if HTTP connection is TLS otherwise false. IsTLS() bool // IsWebSocket returns true if HTTP connection is WebSocket otherwise false. IsWebSocket() bool // Scheme returns the HTTP protocol scheme, `http` or `https`. Scheme() string // RealIP returns the client's network address based on `X-Forwarded-For` // or `X-Real-IP` request header. // The behavior can be configured using `Echo#IPExtractor`. RealIP() string // Path returns the registered path for the handler. Path() string // SetPath sets the registered path for the handler. SetPath(p string) // Param returns path parameter by name. Param(name string) string // ParamNames returns path parameter names. ParamNames() []string // SetParamNames sets path parameter names. SetParamNames(names ...string) // ParamValues returns path parameter values. ParamValues() []string // SetParamValues sets path parameter values. SetParamValues(values ...string) // QueryParam returns the query param for the provided name. QueryParam(name string) string // QueryParams returns the query parameters as `url.Values`. QueryParams() url.Values // QueryString returns the URL query string. QueryString() string // FormValue returns the form field value for the provided name. FormValue(name string) string // FormParams returns the form parameters as `url.Values`. FormParams() (url.Values, error) // FormFile returns the multipart form file for the provided name. FormFile(name string) (*multipart.FileHeader, error) // MultipartForm returns the multipart form. MultipartForm() (*multipart.Form, error) // Cookie returns the named cookie provided in the request. Cookie(name string) (*http.Cookie, error) // SetCookie adds a `Set-Cookie` header in HTTP response. SetCookie(cookie *http.Cookie) // Cookies returns the HTTP cookies sent with the request. Cookies() []*http.Cookie // Get retrieves data from the context. Get(key string) interface{} // Set saves data in the context. Set(key string, val interface{}) // Bind binds path params, query params and the request body into provided type `i`. The default binder // binds body based on Content-Type header. Bind(i interface{}) error // Validate validates provided `i`. It is usually called after `Context#Bind()`. // Validator must be registered using `Echo#Validator`. Validate(i interface{}) error // Render renders a template with data and sends a text/html response with status // code. Renderer must be registered using `Echo.Renderer`. Render(code int, name string, data interface{}) error // HTML sends an HTTP response with status code. HTML(code int, html string) error // HTMLBlob sends an HTTP blob response with status code. HTMLBlob(code int, b []byte) error // String sends a string response with status code. String(code int, s string) error // JSON sends a JSON response with status code. JSON(code int, i interface{}) error // JSONPretty sends a pretty-print JSON with status code. JSONPretty(code int, i interface{}, indent string) error // JSONBlob sends a JSON blob response with status code. JSONBlob(code int, b []byte) error // JSONP sends a JSONP response with status code. It uses `callback` to construct // the JSONP payload. JSONP(code int, callback string, i interface{}) error // JSONPBlob sends a JSONP blob response with status code. It uses `callback` // to construct the JSONP payload. JSONPBlob(code int, callback string, b []byte) error // XML sends an XML response with status code. XML(code int, i interface{}) error // XMLPretty sends a pretty-print XML with status code. XMLPretty(code int, i interface{}, indent string) error // XMLBlob sends an XML blob response with status code. XMLBlob(code int, b []byte) error // Blob sends a blob response with status code and content type. Blob(code int, contentType string, b []byte) error // Stream sends a streaming response with status code and content type. Stream(code int, contentType string, r io.Reader) error // File sends a response with the content of the file. File(file string) error // Attachment sends a response as attachment, prompting client to save the // file. Attachment(file string, name string) error // Inline sends a response as inline, opening the file in the browser. Inline(file string, name string) error // NoContent sends a response with no body and a status code. NoContent(code int) error // Redirect redirects the request to a provided URL with status code. Redirect(code int, url string) error // Error invokes the registered global HTTP error handler. Generally used by middleware. // A side-effect of calling global error handler is that now Response has been committed (sent to the client) and // middlewares up in chain can not change Response status code or Response body anymore. // // Avoid using this method in handlers as no middleware will be able to effectively handle errors after that. Error(err error) // Handler returns the matched handler by router. Handler() HandlerFunc // SetHandler sets the matched handler by router. SetHandler(h HandlerFunc) // Logger returns the `Logger` instance. Logger() Logger // SetLogger Set the logger SetLogger(l Logger) // Echo returns the `Echo` instance. Echo() *Echo // Reset resets the context after request completes. It must be called along // with `Echo#AcquireContext()` and `Echo#ReleaseContext()`. // See `Echo#ServeHTTP()` Reset(r *http.Request, w http.ResponseWriter) } context struct { request *http.Request response *Response path string pnames []string pvalues []string query url.Values handler HandlerFunc store Map echo *Echo logger Logger lock sync.RWMutex } ) const ( // ContextKeyHeaderAllow is set by Router for getting value for `Allow` header in later stages of handler call chain. // Allow header is mandatory for status 405 (method not found) and useful for OPTIONS method requests. // It is added to context only when Router does not find matching method handler for request. ContextKeyHeaderAllow = "echo_header_allow" ) const ( defaultMemory = 32 << 20 // 32 MB indexPage = "index.html" defaultIndent = " " ) func (c *context) writeContentType(value string) { header := c.Response().Header() if header.Get(HeaderContentType) == "" { header.Set(HeaderContentType, value) } } func (c *context) Request() *http.Request { return c.request } func (c *context) SetRequest(r *http.Request) { c.request = r } func (c *context) Response() *Response { return c.response } func (c *context) SetResponse(r *Response) { c.response = r } func (c *context) IsTLS() bool { return c.request.TLS != nil } func (c *context) IsWebSocket() bool { upgrade := c.request.Header.Get(HeaderUpgrade) return strings.EqualFold(upgrade, "websocket") } func (c *context) Scheme() string { // Can't use `r.Request.URL.Scheme` // See: https://groups.google.com/forum/#!topic/golang-nuts/pMUkBlQBDF0 if c.IsTLS() { return "https" } if scheme := c.request.Header.Get(HeaderXForwardedProto); scheme != "" { return scheme } if scheme := c.request.Header.Get(HeaderXForwardedProtocol); scheme != "" { return scheme } if ssl := c.request.Header.Get(HeaderXForwardedSsl); ssl == "on" { return "https" } if scheme := c.request.Header.Get(HeaderXUrlScheme); scheme != "" { return scheme } return "http" } func (c *context) RealIP() string { if c.echo != nil && c.echo.IPExtractor != nil { return c.echo.IPExtractor(c.request) } // Fall back to legacy behavior if ip := c.request.Header.Get(HeaderXForwardedFor); ip != "" { i := strings.IndexAny(ip, ",") if i > 0 { xffip := strings.TrimSpace(ip[:i]) xffip = strings.TrimPrefix(xffip, "[") xffip = strings.TrimSuffix(xffip, "]") return xffip } return ip } if ip := c.request.Header.Get(HeaderXRealIP); ip != "" { ip = strings.TrimPrefix(ip, "[") ip = strings.TrimSuffix(ip, "]") return ip } ra, _, _ := net.SplitHostPort(c.request.RemoteAddr) return ra } func (c *context) Path() string { return c.path } func (c *context) SetPath(p string) { c.path = p } func (c *context) Param(name string) string { for i, n := range c.pnames { if i < len(c.pvalues) { if n == name { return c.pvalues[i] } } } return "" } func (c *context) ParamNames() []string { return c.pnames } func (c *context) SetParamNames(names ...string) { c.pnames = names l := len(names) if *c.echo.maxParam < l { *c.echo.maxParam = l } if len(c.pvalues) < l { // Keeping the old pvalues just for backward compatibility, but it sounds that doesn't make sense to keep them, // probably those values will be overriden in a Context#SetParamValues newPvalues := make([]string, l) copy(newPvalues, c.pvalues) c.pvalues = newPvalues } } func (c *context) ParamValues() []string { return c.pvalues[:len(c.pnames)] } func (c *context) SetParamValues(values ...string) { // NOTE: Don't just set c.pvalues = values, because it has to have length c.echo.maxParam at all times // It will brake the Router#Find code limit := len(values) if limit > *c.echo.maxParam { limit = *c.echo.maxParam } for i := 0; i < limit; i++ { c.pvalues[i] = values[i] } } func (c *context) QueryParam(name string) string { if c.query == nil { c.query = c.request.URL.Query() } return c.query.Get(name) } func (c *context) QueryParams() url.Values { if c.query == nil { c.query = c.request.URL.Query() } return c.query } func (c *context) QueryString() string { return c.request.URL.RawQuery } func (c *context) FormValue(name string) string { return c.request.FormValue(name) } func (c *context) FormParams() (url.Values, error) { if strings.HasPrefix(c.request.Header.Get(HeaderContentType), MIMEMultipartForm) { if err := c.request.ParseMultipartForm(defaultMemory); err != nil { return nil, err } } else { if err := c.request.ParseForm(); err != nil { return nil, err } } return c.request.Form, nil } func (c *context) FormFile(name string) (*multipart.FileHeader, error) { f, fh, err := c.request.FormFile(name) if err != nil { return nil, err } f.Close() return fh, nil } func (c *context) MultipartForm() (*multipart.Form, error) { err := c.request.ParseMultipartForm(defaultMemory) return c.request.MultipartForm, err } func (c *context) Cookie(name string) (*http.Cookie, error) { return c.request.Cookie(name) } func (c *context) SetCookie(cookie *http.Cookie) { http.SetCookie(c.Response(), cookie) } func (c *context) Cookies() []*http.Cookie { return c.request.Cookies() } func (c *context) Get(key string) interface{} { c.lock.RLock() defer c.lock.RUnlock() return c.store[key] } func (c *context) Set(key string, val interface{}) { c.lock.Lock() defer c.lock.Unlock() if c.store == nil { c.store = make(Map) } c.store[key] = val } func (c *context) Bind(i interface{}) error { return c.echo.Binder.Bind(i, c) } func (c *context) Validate(i interface{}) error { if c.echo.Validator == nil { return ErrValidatorNotRegistered } return c.echo.Validator.Validate(i) } func (c *context) Render(code int, name string, data interface{}) (err error) { if c.echo.Renderer == nil { return ErrRendererNotRegistered } buf := new(bytes.Buffer) if err = c.echo.Renderer.Render(buf, name, data, c); err != nil { return } return c.HTMLBlob(code, buf.Bytes()) } func (c *context) HTML(code int, html string) (err error) { return c.HTMLBlob(code, []byte(html)) } func (c *context) HTMLBlob(code int, b []byte) (err error) { return c.Blob(code, MIMETextHTMLCharsetUTF8, b) } func (c *context) String(code int, s string) (err error) { return c.Blob(code, MIMETextPlainCharsetUTF8, []byte(s)) } func (c *context) jsonPBlob(code int, callback string, i interface{}) (err error) { indent := "" if _, pretty := c.QueryParams()["pretty"]; c.echo.Debug || pretty { indent = defaultIndent } c.writeContentType(MIMEApplicationJavaScriptCharsetUTF8) c.response.WriteHeader(code) if _, err = c.response.Write([]byte(callback + "(")); err != nil { return } if err = c.echo.JSONSerializer.Serialize(c, i, indent); err != nil { return } if _, err = c.response.Write([]byte(");")); err != nil { return } return } func (c *context) json(code int, i interface{}, indent string) error { c.writeContentType(MIMEApplicationJSONCharsetUTF8) c.response.Status = code return c.echo.JSONSerializer.Serialize(c, i, indent) } func (c *context) JSON(code int, i interface{}) (err error) { indent := "" if _, pretty := c.QueryParams()["pretty"]; c.echo.Debug || pretty { indent = defaultIndent } return c.json(code, i, indent) } func (c *context) JSONPretty(code int, i interface{}, indent string) (err error) { return c.json(code, i, indent) } func (c *context) JSONBlob(code int, b []byte) (err error) { return c.Blob(code, MIMEApplicationJSONCharsetUTF8, b) } func (c *context) JSONP(code int, callback string, i interface{}) (err error) { return c.jsonPBlob(code, callback, i) } func (c *context) JSONPBlob(code int, callback string, b []byte) (err error) { c.writeContentType(MIMEApplicationJavaScriptCharsetUTF8) c.response.WriteHeader(code) if _, err = c.response.Write([]byte(callback + "(")); err != nil { return } if _, err = c.response.Write(b); err != nil { return } _, err = c.response.Write([]byte(");")) return } func (c *context) xml(code int, i interface{}, indent string) (err error) { c.writeContentType(MIMEApplicationXMLCharsetUTF8) c.response.WriteHeader(code) enc := xml.NewEncoder(c.response) if indent != "" { enc.Indent("", indent) } if _, err = c.response.Write([]byte(xml.Header)); err != nil { return } return enc.Encode(i) } func (c *context) XML(code int, i interface{}) (err error) { indent := "" if _, pretty := c.QueryParams()["pretty"]; c.echo.Debug || pretty { indent = defaultIndent } return c.xml(code, i, indent) } func (c *context) XMLPretty(code int, i interface{}, indent string) (err error) { return c.xml(code, i, indent) } func (c *context) XMLBlob(code int, b []byte) (err error) { c.writeContentType(MIMEApplicationXMLCharsetUTF8) c.response.WriteHeader(code) if _, err = c.response.Write([]byte(xml.Header)); err != nil { return } _, err = c.response.Write(b) return } func (c *context) Blob(code int, contentType string, b []byte) (err error) { c.writeContentType(contentType) c.response.WriteHeader(code) _, err = c.response.Write(b) return } func (c *context) Stream(code int, contentType string, r io.Reader) (err error) { c.writeContentType(contentType) c.response.WriteHeader(code) _, err = io.Copy(c.response, r) return } func (c *context) Attachment(file, name string) error { return c.contentDisposition(file, name, "attachment") } func (c *context) Inline(file, name string) error { return c.contentDisposition(file, name, "inline") } var quoteEscaper = strings.NewReplacer("\\", "\\\\", `"`, "\\\"") func (c *context) contentDisposition(file, name, dispositionType string) error { c.response.Header().Set(HeaderContentDisposition, fmt.Sprintf(`%s; filename="%s"`, dispositionType, quoteEscaper.Replace(name))) return c.File(file) } func (c *context) NoContent(code int) error { c.response.WriteHeader(code) return nil } func (c *context) Redirect(code int, url string) error { if code < 300 || code > 308 { return ErrInvalidRedirectCode } c.response.Header().Set(HeaderLocation, url) c.response.WriteHeader(code) return nil } func (c *context) Error(err error) { c.echo.HTTPErrorHandler(err, c) } func (c *context) Echo() *Echo { return c.echo } func (c *context) Handler() HandlerFunc { return c.handler } func (c *context) SetHandler(h HandlerFunc) { c.handler = h } func (c *context) Logger() Logger { res := c.logger if res != nil { return res } return c.echo.Logger } func (c *context) SetLogger(l Logger) { c.logger = l } func (c *context) Reset(r *http.Request, w http.ResponseWriter) { c.request = r c.response.reset(w) c.query = nil c.handler = NotFoundHandler c.store = nil c.path = "" c.pnames = nil c.logger = nil // NOTE: Don't reset because it has to have length c.echo.maxParam at all times for i := 0; i < *c.echo.maxParam; i++ { c.pvalues[i] = "" } }