問題描述
Мадэль, вызначаная ў выглядзе? (A model defined in a view?)
I'm working on a website which will be used all over the world and has to be highly disponible at anytime anywhere on the planet. That's why I try to use all the possible tricks to reduce at maximum the need of recompiling/restarting the website when minor maintenances must occur.
The ability in Asp.Net MVC to edit a view and have it automatically and dynamically recompiled by the framework without service interruption is really great and perfectly fits my needs. But its interest is strongly limited if I cannot edit the underlying model in a similar way and must recompile the whole stuff.
So my question : it is possible in any way (even an awful, hacky one) to define the view model class right inside the view itself in a code block ?
Otherwise, which trails could I explore to achieve a 'hot‑editable' website (I mean : whose parts could be recompiled while the site is still alive, with changes taken into account straight away) ?
Thank you so much in advance ! :‑)
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參考解法
方法 1:
If you are that concerned about performance and up time, consider using a server farm to host your site. When you need to make updates, you can take each server down separately so that your site is always available.
However, most deployments only take a few seconds. Your application may need more or less time to spin up (EF view generation may take 10‑20 secs for example), but as long as you update during off peak hours you should be fine.
Also, I would NEVER EVER recommend changing code on a live server. You will break something eventually.
方法 2:
Eventually I managed to achieve the goal with another strategy. All views have the same model called DataSource which globally is a recordset open before the rendering and closed after (if needed, reads are performed by the Razor code inside the view).
The column list of the recordset may change live without making the site crash.
For forms and validation, metadata taken from the database about the underlying stored procedure lead to a code emission which dynamically create a c# type, and that's it. Despite a new type is generated each time the sp is changed, the app pool recycling rate prevents too many obsolete types zombiing in memory.