50 lines
1.5 KiB
Go
50 lines
1.5 KiB
Go
package chi
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import "net/http"
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// Chain returns a Middlewares type from a slice of middleware handlers.
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func Chain(middlewares ...func(http.Handler) http.Handler) Middlewares {
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return Middlewares(middlewares)
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}
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// Handler builds and returns a http.Handler from the chain of middlewares,
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// with `h http.Handler` as the final handler.
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func (mws Middlewares) Handler(h http.Handler) http.Handler {
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return &ChainHandler{mws, h, chain(mws, h)}
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}
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// HandlerFunc builds and returns a http.Handler from the chain of middlewares,
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// with `h http.Handler` as the final handler.
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func (mws Middlewares) HandlerFunc(h http.HandlerFunc) http.Handler {
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return &ChainHandler{mws, h, chain(mws, h)}
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}
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// ChainHandler is a http.Handler with support for handler composition and
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// execution.
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type ChainHandler struct {
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Middlewares Middlewares
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Endpoint http.Handler
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chain http.Handler
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}
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func (c *ChainHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
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c.chain.ServeHTTP(w, r)
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}
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// chain builds a http.Handler composed of an inline middleware stack and endpoint
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// handler in the order they are passed.
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func chain(middlewares []func(http.Handler) http.Handler, endpoint http.Handler) http.Handler {
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// Return ahead of time if there aren't any middlewares for the chain
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if len(middlewares) == 0 {
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return endpoint
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}
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// Wrap the end handler with the middleware chain
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h := middlewares[len(middlewares)-1](endpoint)
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for i := len(middlewares) - 2; i >= 0; i-- {
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h = middlewares[i](h)
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}
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return h
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}
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