When would you use multiple app.use, and when would you use multiple functions in one app.use?

Question

Thanks!

Luis Marsano · Accepted Answer

The documentation for app.METHOD() (https://expressjs.com/en/4x/api.html#app.METHOD) and app.use() (https://expressjs.com/en/4x/api.html#app.use) explains.
You would list multiple callbacks in a single app.use call when you want to bypass the remainder of the list with a call to next('route').
Check out the documentation for more information.

Tom Geraghty · Answer

I believe he is demonstrating that you can chain multiple functions to a single app.use and also that you can call app.use as many times as you want in a row and they will both act in the same, predictable way. As well as how multiple pieces of middleware can act on the same data stream.
In writing your own application it's likely best to use only one app.use with a chain of functions after it to reduce complexity. 
Your team's style choice may be different especially if they write separate modules that all act on the same data.

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Peter Lu

Peter Lu

When would you use multiple app.use, and when would you use multiple functions in one app.use?

2 Answers

Luis Marsano

Luis Marsano

Kevin Gates

Kevin Gates

Tom Geraghty

Tom Geraghty