Context enhancement

CHANGELOG.md

@@ -3,6 +3,17 @@ Change Log
 
 under development
 -----------------
+- Add `Context.JSON` to send JSON response.
+- Add `Context.String` to send string response.
+- Add `Context.XML` to send XML response.
+- `Content.SetContentTypeJSON` and `Content.SetContentTypeXML` append `charset=utf-8` to content type header.
+- Add `Context.HTML` to send HTML response.
+- Add `Context.Cookie` and `Context.Cookies`.
+- Add `Context.FormValue`.
+- Add `Context.PostFormValue`.
+- Add `Context.QueryString`.
+- Add `Context.QueryParams` and `Context.QueryParam`.
+- Add `Context.JSONP` and `Context.JSONPCallback`.
 
 v1.8.1 April 2, 2020
 --------------------

context.go

@@ -6,8 +6,12 @@ package clevergo
 
 import (
 	"context"
+	"encoding/json"
+	"encoding/xml"
+	"fmt"
 	"io"
 	"net/http"
+	"net/url"
 )
 
 // Context contains incoming request, route, params and manages outgoing response.
@@ -16,6 +20,7 @@ type Context struct {
 	Route    *Route
 	Request  *http.Request
 	Response http.ResponseWriter
+	query    url.Values
 }
 
 func newContext(w http.ResponseWriter, r *http.Request) *Context {
@@ -30,6 +35,7 @@ func (ctx *Context) reset() {
 	ctx.Route = nil
 	ctx.Response = nil
 	ctx.Request = nil
+	ctx.query = nil
 }
 
 // Error is a shortcut of http.Error.
@@ -64,12 +70,22 @@ func (ctx *Context) SetContentTypeText() {
 
 // SetContentTypeJSON sets the content type as JSON.
 func (ctx *Context) SetContentTypeJSON() {
-	ctx.SetContentType("application/json")
+	ctx.SetContentType("application/json; charset=utf-8")
 }
 
 // SetContentTypeXML sets the content type as XML.
 func (ctx *Context) SetContentTypeXML() {
-	ctx.SetContentType("application/xml")
+	ctx.SetContentType("application/xml; charset=utf-8")
+}
+
+// Cookie is a shortcut of http.Request.Cookie.
+func (ctx *Context) Cookie(name string) (*http.Cookie, error) {
+	return ctx.Request.Cookie(name)
+}
+
+// Cookies is a shortcut of http.Request.Cookies.
+func (ctx *Context) Cookies() []*http.Cookie {
+	return ctx.Request.Cookies()
 }
 
 // SetCookie is a shortcut of http.SetCookie.
@@ -146,3 +162,102 @@ func (ctx *Context) IsPut() bool {
 func (ctx *Context) GetHeader(name string) string {
 	return ctx.Request.Header.Get(name)
 }
+
+// JSON sends JSON response with status code, it also sets
+// Content-Type as "application/json".
+func (ctx *Context) JSON(code int, data interface{}) error {
+	bs, err := json.Marshal(data)
+	if err != nil {
+		return err
+	}
+
+	ctx.SetContentTypeJSON()
+	ctx.Response.WriteHeader(code)
+	_, err = ctx.Response.Write(bs)
+	return err
+}
+
+// JSONP is a shortcut of JSONPCallback with specified callback param name.
+func (ctx *Context) JSONP(code int, data interface{}) error {
+	return ctx.JSONPCallback(code, "callback", data)
+}
+
+// JSONPCallback sends JSONP response with status code, it also sets
+// Content-Type as "application/javascript".
+// If the callback is not present, returns JSON response instead.
+func (ctx *Context) JSONPCallback(code int, callback string, data interface{}) error {
+	fn := ctx.QueryParam(callback)
+	if fn == "" {
+		return ctx.JSON(code, data)
+	}
+
+	bs, err := json.Marshal(data)
+	if err != nil {
+		return err
+	}
+
+	ctx.SetContentType("application/javascript; charset=utf-8")
+	ctx.Response.WriteHeader(code)
+	_, err = ctx.WriteString(fmt.Sprintf("%s(%s)", fn, bs))
+	return err
+}
+
+// String send string response with status code, it also sets
+// Content-Type as "text/plain; charset=utf-8".
+func (ctx *Context) String(code int, s string) error {
+	ctx.SetContentTypeText()
+	ctx.Response.WriteHeader(code)
+	_, err := ctx.WriteString(s)
+	return err
+}
+
+// XML sends XML response with status code, it also sets
+// Content-Type as "application/xml".
+func (ctx *Context) XML(code int, data interface{}) error {
+	bs, err := xml.Marshal(data)
+	if err != nil {
+		return err
+	}
+
+	ctx.SetContentTypeXML()
+	ctx.Response.WriteHeader(code)
+	_, err = ctx.Response.Write(bs)
+	return err
+}
+
+// HTML sends HTML response with status code, it also sets
+// Content-Type as "text/html".
+func (ctx *Context) HTML(code int, html string) error {
+	ctx.SetContentTypeHTML()
+	ctx.Response.WriteHeader(code)
+	_, err := ctx.WriteString(html)
+	return err
+}
+
+// FormValue is a shortcut of http.Request.FormValue.
+func (ctx *Context) FormValue(key string) string {
+	return ctx.Request.FormValue(key)
+}
+
+// PostFormValue is a shortcut of http.Request.PostFormValue.
+func (ctx *Context) PostFormValue(key string) string {
+	return ctx.Request.PostFormValue(key)
+}
+
+// QueryString returns the raw query of request URL.
+func (ctx *Context) QueryString() string {
+	return ctx.Request.URL.RawQuery
+}
+
+// QueryParam returns the param for the given key.
+func (ctx *Context) QueryParam(key string) string {
+	return ctx.QueryParams().Get(key)
+}
+
+// QueryParams returns request URL values.
+func (ctx *Context) QueryParams() url.Values {
+	if ctx.query == nil {
+		ctx.query = ctx.Request.URL.Query()
+	}
+	return ctx.query
+}