The order of the execution of codes and functions in sails.js and node.js

Question

Please look at the picture below and help me

I want to do something like this:

I want first part A to be fully executed Then run section B, Because in the first part(A) must the file uploaded compeletly to make the uploaded file name assign to global_d variable, i need this variable in part B.

The next question is how to access a local variable(in this case global_d) from within nested callback functions(in this case part A)?

Please explain me with examples

I hope I have expressed my question carefully.
thank you

Answer 1

The callback function is called when the upload is complete.

Put the call to Book.update inside it.

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If you want to avoid nesting, the use Promises and see Removing Nested Promises