how to restrict an API request to not enter in API?

Hello,

You can do it By RAML validations (if you dont have Any idea about RAML),

Please use this links - https://docs.mulesoft.com/api-manager/1.x/tutorial-design-an-api

https://docs.mulesoft.com/api-manager/1.x/design-raml-api-task

request will not enter to you main flows of API , api kit router will throw the error after RAMlL validation if it didnt pass.

use this link for apikit router based API's- https://docs.mulesoft.com/apikit/4.x/apikit-4-raml-flow-concept

Now, create a JSON schema in RAML and appply a validation rule there

let's suppose you have the request as below , create a JSON file with Name (requestValidation.json )

{
      field1: "",
      field2: ""
}

Then for this create a schema validaiton file (requstValidation.json)as below

{ 
	"$schema": "http://json-schema.org/draft-04/schema#",
	"type": "object",
	"properties": {
		"field1": {
			"type": "string"
		},
		"field2": {
			"type": "string"
		}
  },
 "anyOf": [{
  "required" : ["field1"]
 }, {
  "required" : ["field2"]
 }]
}
 

you can validate this schema using this - https://www.jsonschemavalidator.net/

test it by tweaking your input.After this include schmea file in you resource as below example

/account:
    post:
	body:
		application/json:
			schema: !include requestValidation.json
			example: !include requestValidation.json 

for more understanding on desiginig the RAML go thorugh these links also

https://github.com/raml-apis/Uber/blob/staging/api.raml

https://github.com/mulesoft/raml-tutorial-200/blob/master/jukebox-api.raml

I have attached a zip file that you can use to undersatnd RAML designing kind of best practices. (I created this for other user who asked to design a RAML).it doesnt have JSON schema validation but you will get some knowledge.

Happy Learning !!

Regards,

Anurag Sharma