29 lines
926 B
Go
29 lines
926 B
Go
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package endpoint
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import (
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"context"
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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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// 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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// Middleware is a chainable behavior modifier for endpoints.
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type Middleware func(Endpoint) Endpoint
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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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