API Gateway recently released some enhancements to customer authorizers, including a new REQUEST type authorizer which is passed much more information from the incoming request. While the base path is not explicitly called out, it may be present in one of the path parameters.
{
"type": "REQUEST",
"methodArn": "arn:aws:execute-api:us-east-1:123456789012:s4x3opwd6i/test/GET/request",
"resource": "/request",
"path": "/request",
"httpMethod": "GET",
"headers": {
"X-AMZ-Date": "20170718T062915Z",
"Accept": "*/*",
"HeaderAuth1": "headerValue1",
"CloudFront-Viewer-Country": "US",
"CloudFront-Forwarded-Proto": "https",
"CloudFront-Is-Tablet-Viewer": "false",
"CloudFront-Is-Mobile-Viewer": "false",
"User-Agent": "...",
"X-Forwarded-Proto": "https",
"CloudFront-Is-SmartTV-Viewer": "false",
"Host": "....execute-api.us-east-1.amazonaws.com",
"Accept-Encoding": "gzip, deflate",
"X-Forwarded-Port": "443",
"X-Amzn-Trace-Id": "...",
"Via": "...cloudfront.net (CloudFront)",
"X-Amz-Cf-Id": "...",
"X-Forwarded-For": "..., ...",
"Postman-Token": "...",
"cache-control": "no-cache",
"CloudFront-Is-Desktop-Viewer": "true",
"Content-Type": "application/x-www-form-urlencoded"
},
"queryStringParameters": {
"QueryString1": "queryValue1"
},
"pathParameters": {},
"stageVariables": {
"StageVar1": "stageValue1"
},
"requestContext": {
"path": "/request",
"accountId": "123456789012",
"resourceId": "05c7jb",
"stage": "test",
"requestId": "...",
"identity": {
"apiKey": "...",
"sourceIp": "..."
},
"resourcePath": "/request",
"httpMethod": "GET",
"apiId": "s4x3opwd6i"
}
}
From documentation here