You must implemented a system which detect whether api calls to a certain path are valid.
Design 1 end point which will define the model of the apis, So
for example
path salt-sec path
method: post
query params: {name(string, int), required:true/false
header :name(string, int) ,required:true/false...
body params:name(string, boolean).. ,required:true/false
So basically defining the params and what is a valid type of param for the specific path and method for each of the header, query param segments.
Second part
Define another end point which receives a request and checks based on the models saved if its a valid request
What would the client using this type of system want?
Describe the type data base and type of storage you'll use.
"They want nosql but mysql can work if you reuse params frequently. They probably only work with nosql..."
Describe the scale of a system like this.