32 lines
1.1 KiB
ReStructuredText
32 lines
1.1 KiB
ReStructuredText
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Architecture
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============
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Handlers are similar to a "plugin" concept in that multiple handlers
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may be installed e.g. by different packages. But whereas one might
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"enable" multiple plugins, only *one* handler may be used, for a given
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purpose.
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There can be many "types" of handlers; each is responsible for a
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certain aspect of the overall app. So it can be thought of as,
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"*Which* plugin should *handle* this aspect of the app?"
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What a Handler Does
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-------------------
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Each type of handler does something different. For instance there
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might be an "auth handler" responsible for authenticating user
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credentials.
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The app itself will define the need for a handler. For instance if a
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user login mechanism is needed, then the app might define the "auth
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handler" (e.g. ``AuthHandler``) base class, and add a way to locate
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and use it at runtime.
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Other packages might then also define "auth handlers" derived from the
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base class, and perhaps a way for the app to locate them as well.
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The app should probably have a way for the "choice" of auth handler to
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be configurable, and possibly expose this choice via admin UI.
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