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57 lines
1.5 KiB
Markdown
57 lines
1.5 KiB
Markdown
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cowboy_middleware
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=================
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The `cowboy_middleware` behaviour defines the interface used
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by Cowboy middleware modules.
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Middlewares process the request sequentially in the order they
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are configured.
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Types
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-----
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### env() = [{atom(), any()}]
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> The environment variable.
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>
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> One is created for every request. It is passed to each
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> middleware module executed and subsequently returned,
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> optionally with its contents modified.
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Callbacks
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---------
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### execute(Req, Env)
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-> {ok, Req, Env}
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| {suspend, Module, Function, Args}
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| {halt, Req}
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| {error, StatusCode, Req}
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> Types:
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> * Req = cowboy_req:req()
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> * Env = env()
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> * Module = module()
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> * Function = atom()
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> * Args = [any()]
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> * StatusCode = cowboy:http_status()
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>
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> Execute the middleware.
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>
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> The `ok` return value indicates that everything went well
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> and that Cowboy should continue processing the request. A
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> response may or may not have been sent.
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>
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> The `suspend` return value will hibernate the process until
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> an Erlang message is received. Note that when resuming, any
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> previous stacktrace information will be gone.
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>
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> The `halt` return value stops Cowboy from doing any further
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> processing of the request, even if there are middlewares
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> that haven't been executed yet. The connection may be left
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> open to receive more requests from the client.
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>
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> The `error` return value sends an error response identified
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> by the `StatusCode` and then proceeds to terminate the
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> connection. Middlewares that haven't been executed yet
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> will not be called.
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