29 lines
		
	
	
		
			943 B
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			29 lines
		
	
	
		
			943 B
		
	
	
	
		
			Go
		
	
	
	
	
	
| package endpoint
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| 
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| import (
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| 	"golang.org/x/net/context"
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| )
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| 
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| // Endpoint is the fundamental building block of servers and clients.
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| // It represents a single RPC method.
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| type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)
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| 
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| // Nop is an endpoint that does nothing and returns a nil error.
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| // Useful for tests.
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| func Nop(context.Context, interface{}) (interface{}, error) { return struct{}{}, nil }
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| 
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| // Middleware is a chainable behavior modifier for endpoints.
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| type Middleware func(Endpoint) Endpoint
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| 
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| // Chain is a helper function for composing middlewares. Requests will
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| // traverse them in the order they're declared. That is, the first middleware
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| // is treated as the outermost middleware.
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| func Chain(outer Middleware, others ...Middleware) Middleware {
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| 	return func(next Endpoint) Endpoint {
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| 		for i := len(others) - 1; i >= 0; i-- { // reverse
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| 			next = others[i](next)
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| 		}
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| 		return outer(next)
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| 	}
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| }
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