Q:

I'm trying to curl a GET request

I'm quite new to openstack and software development, but here goes.
i'm trying to curl a GET request via AWS Api Gateway.
the curl looks like this:
curl -H "Accept: application/json" -H "Content-Type: application/json" -i GET -d 'name=Claus&username=gettest&password=test' https://xy8fbbpvak.execute-api.eu-west-1.amazonaws.com/prod/adduser

but it gives me this response:
curl: (6) Could not resolve host: GET
HTTP/1.1 403 Forbidden
Content-Type: application/json
Content-Length: 43
Connection: keep-alive
Date: Tue, 18 Jul 2017 06:10:08 GMT
x-amzn-RequestId: c049f3e5-6b7f-11e7-a380-d966a8908f27
x-amzn-ErrorType: MissingAuthenticationTokenException
X-Cache: Error from cloudfront
Via: 1.1 dc81da318a4ae20e51ccfd9463219596.cloudfront.net (CloudFront)
X-Amz-Cf-Id: BI3LX_cwBic2EtCleIHd6yT0B1p4GRoqEbqx85L1nO2UUafPKXC2iQ==

{"message":"Missing Authentication Token"}

The method in AWS API Gateway doesn't need authorization or a token. 
I'm really not sure what i'm doing wrong? please tell me if you need more info.

A:

The message {"message":"Missing Authentication Token"} does not necessarily means that it needs an authorization or a token, but you receive the same error if you request a URL that doesn't exist
You need to make sure you're using the correct HTTP method and resource path to a valid resource.
From your example, you're using a GET and the action is prod/adduser, that does not sound too good to me, addUser would generally be made on PUT or POST when you design your API.
Also make sure to deploy your API changes, when you test from the API gateway, its a staging area but its not deployed

