58 lines
2.1 KiB
Racket
58 lines
2.1 KiB
Racket
#lang scribble/doc
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@(require "web-server.ss")
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@title[]{Serializable Continuations}
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@(require (for-label web-server/lang/abort-resume
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"dummy-stateless-servlet.ss"
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scheme/serialize))
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@defmodule[web-server/lang/abort-resume]{
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The main purpose of the stateless language is to provide serializable continuations to your servlet.
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@defproc[(call-with-serializable-current-continuation [response-generator (continuation? . -> . any)])
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any]{
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Captures the current continuation in a serializable way and calls @scheme[response-generator] with it, returning the result.
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This potentially uses resources of the current servlet's @scheme[manager] if @scheme[serial->native] and @scheme[native->serial] were used
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to capture an untransformable context.
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}
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@defform[(serial->native expr)]{
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@scheme[serial->native] informs the serializing runtime that @scheme[expr] is potentially a call to an untransformed context.
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This sets up the necessary information for
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@scheme[native->serial] to signal to @scheme[call-with-serializable-current-continuation] to capture the native (and thus unserializable) section
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of the context and store it on the server.
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}
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@defform[(native->serial expr)]{
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@scheme[native->serial] informs the serializing runtime that @scheme[expr] marks first expression after returning from an untransformed context.
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This captures the
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untransformed context such that @scheme[call-with-serializable-current-continuation] can store it on the server and reference it from serializable
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continuations.
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For example,
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@schemeblock[
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(build-list
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3
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(lambda (i)
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(call-with-serializable-current-continuation
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(lambda (k) (serialize k)))))
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]
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will fail at runtime because @scheme[build-list] is not transformed. However,
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@schemeblock[
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(serial->native
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(build-list
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3
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(lambda (i)
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(native->serial
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(call-with-serializable-current-continuation
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(lambda (k) (serialize k)))))))
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]
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will succeed and @scheme[k] will reference a cell in the current servlet's @scheme[manager] that stores the part of the continuation in
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@scheme[build-list].
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}
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}
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