(#1554) Add support for all common compressions (write and read)

- Remove the context.Context interface and export the *context, the iris.Context now points to the pointer\nSupport compression and rate limiting in the FileServer\nBit of code organisation


Former-commit-id: ad1c61bf968059510c6be9e7f2cceec7da70ba17

context/pool.go

@@ -6,41 +6,26 @@ import (
 )
 
 // Pool is the context pool, it's used inside router and the framework by itself.
-//
-// It's the only one real implementation inside this package because it used widely.
 type Pool struct {
-	pool    *sync.Pool
-	newFunc func() Context // we need a field otherwise is not working if we change the return value
+	pool *sync.Pool
 }
 
 // New creates and returns a new context pool.
-func New(newFunc func() Context) *Pool {
-	c := &Pool{pool: &sync.Pool{}, newFunc: newFunc}
-	c.pool.New = func() interface{} { return c.newFunc() }
-	return c
-}
-
-// Attach changes the pool's return value Context.
-//
-// The new Context should explicitly define the `Next()`
-// and `Do(context.Handlers)` functions.
-//
-// Example: https://github.com/kataras/iris/blob/master/_examples/routing/custom-context/method-overriding/main.go
-func (c *Pool) Attach(newFunc func() Context) {
-	c.newFunc = newFunc
+func New(newFunc func() interface{}) *Pool {
+	return &Pool{pool: &sync.Pool{New: newFunc}}
 }
 
 // Acquire returns a Context from pool.
 // See Release.
-func (c *Pool) Acquire(w http.ResponseWriter, r *http.Request) Context {
-	ctx := c.pool.Get().(Context)
+func (c *Pool) Acquire(w http.ResponseWriter, r *http.Request) *Context {
+	ctx := c.pool.Get().(*Context)
 	ctx.BeginRequest(w, r)
 	return ctx
 }
 
 // Release puts a Context back to its pull, this function releases its resources.
 // See Acquire.
-func (c *Pool) Release(ctx Context) {
+func (c *Pool) Release(ctx *Context) {
 	ctx.EndRequest()
 	c.pool.Put(ctx)
 }
@@ -48,6 +33,6 @@ func (c *Pool) Release(ctx Context) {
 // ReleaseLight will just release the object back to the pool, but the
 // clean method is caller's responsibility now, currently this is only used
 // on `SPABuilder`.
-func (c *Pool) ReleaseLight(ctx Context) {
+func (c *Pool) ReleaseLight(ctx *Context) {
 	c.pool.Put(ctx)
 }