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evanritscher
10,209 PointsWhere are req and res originally defined?
I'm working through Express and Node videos and have a question on req and res specifically as it relates to middleware.
In Expressjs, we can use app.use() with a middleware function that can eventually be sent to the next middleware function. If we manipulate the req e.g. update a property on req.params that new value for req is used in the second req middleware function.
My question is, where does the originally req and res come from? Where is req being defined and where is it being initialized as an object? Is this all behind the scenes and hard to actually see in Express?