Cross Site Request Forgery
The XSRF-TOKEN cookie is added to the response of the HTTP request. The cookie is a secure cookie so this is only sent with HTTPS and not HTTP. All HTTP (Not HTTPS) requests will fail and return a 400 response. The cookie is created and added each time a new server url is called, but not for an API call.
The API uses the ValidateAntiForgeryToken attribute to check if the request contains the correct value for the XSRF-TOKEN cookie. If this is incorrect, or not sent, the request is rejected with a 400 response. The attribute is required when data is changed. HTTP GET requests should not require this attribute.
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